Implement multibody joints and the new solver

.github/workflows/rapier-ci-build.yml

@@ -28,13 +28,13 @@ jobs:
     - name: Build rapier3d
       run: cargo build --verbose -p rapier3d;
     - name: Build rapier2d SIMD
-      run: cd build/rapier2d; cargo build --verbose --features simd-stable;
+      run: cd crates/rapier2d; cargo build --verbose --features simd-stable;
     - name: Build rapier3d SIMD
-      run: cd build/rapier3d; cargo build --verbose --features simd-stable;
+      run: cd crates/rapier3d; cargo build --verbose --features simd-stable;
     - name: Build rapier2d SIMD Parallel
-      run: cd build/rapier2d; cargo build --verbose --features simd-stable --features parallel;
+      run: cd crates/rapier2d; cargo build --verbose --features simd-stable --features parallel;
     - name: Build rapier3d SIMD Parallel
-      run: cd build/rapier3d; cargo build --verbose --features simd-stable --features parallel;
+      run: cd crates/rapier3d; cargo build --verbose --features simd-stable --features parallel;
     - name: Run tests
       run: cargo test
     - name: Check rapier_testbed2d
@@ -42,9 +42,9 @@ jobs:
     - name: Check rapier_testbed3d
       run: cargo check --verbose -p rapier_testbed3d;
     - name: Check rapier_testbed2d --features parallel
-      run: cd build/rapier_testbed2d; cargo check --verbose --features parallel;
+      run: cd crates/rapier_testbed2d; cargo check --verbose --features parallel;
     - name: Check rapier_testbed3d --features parallel
-      run: cd build/rapier_testbed3d; cargo check --verbose --features parallel;
+      run: cd crates/rapier_testbed3d; cargo check --verbose --features parallel;
     - name: Check rapier-examples-2d
       run: cargo check -j 1 --verbose -p rapier-examples-2d;
     - name: Check rapier-examples-3d
@@ -57,9 +57,9 @@ jobs:
       - uses: actions/checkout@v2
       - run: rustup target add wasm32-unknown-unknown
       - name: build rapier2d
-        run: cd build/rapier2d && cargo build --verbose --features wasm-bindgen --target wasm32-unknown-unknown;
+        run: cd crates/rapier2d && cargo build --verbose --features wasm-bindgen --target wasm32-unknown-unknown;
       - name: build rapier3d
-        run: cd build/rapier3d && cargo build --verbose --features wasm-bindgen --target wasm32-unknown-unknown;
+        run: cd crates/rapier3d && cargo build --verbose --features wasm-bindgen --target wasm32-unknown-unknown;
   build-wasm-emscripten:
     runs-on: ubuntu-latest
     env:
@@ -68,10 +68,10 @@ jobs:
       - uses: actions/checkout@v2
       - run: rustup target add wasm32-unknown-emscripten
       - name: build rapier2d
-        run: cd build/rapier2d && cargo build --verbose --target wasm32-unknown-emscripten;
+        run: cd crates/rapier2d && cargo build --verbose --target wasm32-unknown-emscripten;
       - name: build rapier3d
-        run: cd build/rapier3d && cargo build --verbose --target wasm32-unknown-emscripten;
+        run: cd crates/rapier3d && cargo build --verbose --target wasm32-unknown-emscripten;
       - name: build rapier2d --features simd-stable
-        run: cd build/rapier2d && cargo build --verbose --target wasm32-unknown-emscripten --features simd-stable;
+        run: cd crates/rapier2d && cargo build --verbose --target wasm32-unknown-emscripten --features simd-stable;
       - name: build rapier3d --features simd-stable
-        run: cd build/rapier3d && cargo build --verbose --target wasm32-unknown-emscripten --features simd-stable;
+        run: cd crates/rapier3d && cargo build --verbose --target wasm32-unknown-emscripten --features simd-stable;

Cargo.toml

@@ -1,21 +1,17 @@
 [workspace]
-members = [ "build/rapier2d", "build/rapier2d-f64", "build/rapier_testbed2d", "examples2d", "benchmarks2d",
-            "build/rapier3d", "build/rapier3d-f64", "build/rapier_testbed3d", "examples3d", "benchmarks3d" ]
+members = [ "crates/rapier2d", "crates/rapier2d-f64", "crates/rapier_testbed2d", "examples2d", "benchmarks2d",
+            "crates/rapier3d", "crates/rapier3d-f64", "crates/rapier_testbed3d", "examples3d", "benchmarks3d" ]
 resolver = "2"
 
 [patch.crates-io]
 #wrapped2d = { git = "https://github.com/Bastacyclop/rust_box2d.git" }
 
 #simba = { path = "../simba" }
-#ncollide2d = { path = "../ncollide/build/ncollide2d" }
-#ncollide3d = { path = "../ncollide/build/ncollide3d" }
-#nphysics2d = { path = "../nphysics/build/nphysics2d" }
-#nphysics3d = { path = "../nphysics/build/nphysics3d" }
 #kiss3d = { path = "../kiss3d" }
-#parry2d = { path = "../parry/build/parry2d" }
-#parry3d = { path = "../parry/build/parry3d" }
-#parry2d-f64 = { path = "../parry/build/parry2d-f64" }
-#parry3d-f64 = { path = "../parry/build/parry3d-f64" }
+#parry2d = { path = "../parry/crates/parry2d" }
+#parry3d = { path = "../parry/crates/parry3d" }
+#parry2d-f64 = { path = "../parry/crates/parry2d-f64" }
+#parry3d-f64 = { path = "../parry/crates/parry3d-f64" }
 #nalgebra = { path = "../nalgebra" }
 
 #kiss3d = { git = "https://github.com/sebcrozet/kiss3d" }
@@ -24,14 +20,10 @@ resolver = "2"
 #parry3d = { git = "https://github.com/dimforge/parry", branch = "special_cases" }
 #parry2d-f64 = { git = "https://github.com/dimforge/parry", branch = "special_cases" }
 #parry3d-f64 = { git = "https://github.com/dimforge/parry", branch = "special_cases" }
-#ncollide2d = { git = "https://github.com/dimforge/ncollide" }
-#ncollide3d = { git = "https://github.com/dimforge/ncollide" }
-#nphysics2d = { git = "https://github.com/dimforge/nphysics" }
-#nphysics3d = { git = "https://github.com/dimforge/nphysics" }
 
 [profile.release]
 #debug = true
-codegen-units = 1
+#codegen-units = 1
 #opt-level = 1
 #lto = true
 

benchmarks2d/Cargo.toml

@@ -2,7 +2,7 @@
 name    = "rapier-benchmarks-2d"
 version = "0.1.0"
 authors = [ "Sébastien Crozet <developer@crozet.re>" ]
-edition = "2018"
+edition = "2021"
 
 [features]
 parallel = [ "rapier2d/parallel", "rapier_testbed2d/parallel" ]
@@ -16,10 +16,10 @@ rand       = "0.8"
 Inflector  = "0.11"
 
 [dependencies.rapier_testbed2d]
-path = "../build/rapier_testbed2d"
+path = "../crates/rapier_testbed2d"
 
 [dependencies.rapier2d]
-path = "../build/rapier2d"
+path = "../crates/rapier2d"
 
 [[bin]]
 name = "all_benchmarks2"

benchmarks2d/balls2.rs

@@ -7,7 +7,9 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
+
     /*
      * Ground
      */
@@ -58,6 +60,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![0.0, 2.5], 5.0);
 }

benchmarks2d/boxes2.rs

@@ -7,7 +7,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -63,6 +64,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![0.0, 50.0], 10.0);
 }

benchmarks2d/capsules2.rs

@@ -7,7 +7,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -65,6 +66,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![0.0, 50.0], 10.0);
 }

benchmarks2d/convex_polygons2.rs

@@ -9,7 +9,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -76,6 +77,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![0.0, 50.0], 10.0);
 }

benchmarks2d/heightfield2.rs

@@ -8,7 +8,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -63,6 +64,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![0.0, 50.0], 10.0);
 }

benchmarks2d/joint_ball2.rs

@@ -7,7 +7,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let mut joints = JointSet::new();
+    let mut impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Create the balls
@@ -41,16 +42,16 @@ pub fn init_world(testbed: &mut Testbed) {
             // Vertical joint.
             if i > 0 {
                 let parent_handle = *body_handles.last().unwrap();
-                let joint = BallJoint::new(Point::origin(), point![0.0, shift]);
-                joints.insert(parent_handle, child_handle, joint);
+                let joint = RevoluteJoint::new().local_anchor2(point![0.0, shift]);
+                impulse_joints.insert(parent_handle, child_handle, joint);
             }
 
             // Horizontal joint.
             if k > 0 {
                 let parent_index = body_handles.len() - numi;
                 let parent_handle = body_handles[parent_index];
-                let joint = BallJoint::new(Point::origin(), point![-shift, 0.0]);
-                joints.insert(parent_handle, child_handle, joint);
+                let joint = RevoluteJoint::new().local_anchor2(point![-shift, 0.0]);
+                impulse_joints.insert(parent_handle, child_handle, joint);
             }
 
             body_handles.push(child_handle);
@@ -60,6 +61,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![numk as f32 * rad, numi as f32 * -rad], 5.0);
 }

benchmarks2d/joint_fixed2.rs

@@ -7,7 +7,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let mut joints = JointSet::new();
+    let mut impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Create the balls
@@ -46,22 +47,18 @@ pub fn init_world(testbed: &mut Testbed) {
                     // Vertical joint.
                     if i > 0 {
                         let parent_handle = *body_handles.last().unwrap();
-                        let joint = FixedJoint::new(
-                            Isometry::identity(),
-                            Isometry::translation(0.0, shift),
-                        );
-                        joints.insert(parent_handle, child_handle, joint);
+                        let joint =
+                            FixedJoint::new().local_frame2(Isometry::translation(0.0, shift));
+                        impulse_joints.insert(parent_handle, child_handle, joint);
                     }
 
                     // Horizontal joint.
                     if k > 0 {
                         let parent_index = body_handles.len() - num;
                         let parent_handle = body_handles[parent_index];
-                        let joint = FixedJoint::new(
-                            Isometry::identity(),
-                            Isometry::translation(-shift, 0.0),
-                        );
-                        joints.insert(parent_handle, child_handle, joint);
+                        let joint =
+                            FixedJoint::new().local_frame2(Isometry::translation(-shift, 0.0));
+                        impulse_joints.insert(parent_handle, child_handle, joint);
                     }
 
                     body_handles.push(child_handle);
@@ -73,6 +70,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![50.0, 50.0], 5.0);
 }

benchmarks2d/joint_prismatic2.rs

@@ -7,7 +7,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let mut joints = JointSet::new();
+    let mut impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Create the balls
@@ -46,12 +47,10 @@ pub fn init_world(testbed: &mut Testbed) {
                     UnitVector::new_normalize(vector![-1.0, 1.0])
                 };
 
-                let mut prism =
-                    PrismaticJoint::new(Point::origin(), axis, point![0.0, shift], axis);
-                prism.limits_enabled = true;
-                prism.limits[0] = -1.5;
-                prism.limits[1] = 1.5;
-                joints.insert(curr_parent, curr_child, prism);
+                let mut prism = PrismaticJoint::new(axis)
+                    .local_anchor2(point![0.0, shift])
+                    .limit_axis([-1.5, 1.5]);
+                impulse_joints.insert(curr_parent, curr_child, prism);
 
                 curr_parent = curr_child;
             }
@@ -61,6 +60,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![80.0, 80.0], 15.0);
 }

benchmarks2d/pyramid2.rs

@@ -7,7 +7,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -50,6 +51,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![0.0, 2.5], 5.0);
 }

benchmarks3d/Cargo.toml

@@ -2,7 +2,7 @@
 name    = "rapier-benchmarks-3d"
 version = "0.1.0"
 authors = [ "Sébastien Crozet <developer@crozet.re>" ]
-edition = "2018"
+edition = "2021"
 
 [features]
 parallel = [ "rapier3d/parallel", "rapier_testbed3d/parallel" ]
@@ -16,10 +16,10 @@ rand       = "0.8"
 Inflector  = "0.11"
 
 [dependencies.rapier_testbed3d]
-path = "../build/rapier_testbed3d"
+path = "../crates/rapier_testbed3d"
 
 [dependencies.rapier3d]
-path = "../build/rapier3d"
+path = "../crates/rapier3d"
 
 [[bin]]
 name = "all_benchmarks3"

benchmarks3d/all_benchmarks3.rs

@@ -58,10 +58,10 @@ pub fn main() {
         ("Stacks", stacks3::init_world),
         ("Pyramid", pyramid3::init_world),
         ("Trimesh", trimesh3::init_world),
-        ("Joint ball", joint_ball3::init_world),
-        ("Joint fixed", joint_fixed3::init_world),
-        ("Joint revolute", joint_revolute3::init_world),
-        ("Joint prismatic", joint_prismatic3::init_world),
+        ("ImpulseJoint ball", joint_ball3::init_world),
+        ("ImpulseJoint fixed", joint_fixed3::init_world),
+        ("ImpulseJoint revolute", joint_revolute3::init_world),
+        ("ImpulseJoint prismatic", joint_prismatic3::init_world),
         ("Keva tower", keva3::init_world),
     ];
 

benchmarks3d/balls3.rs

@@ -7,7 +7,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Create the balls
@@ -48,6 +49,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![100.0, 100.0, 100.0], Point::origin());
 }

benchmarks3d/boxes3.rs

@@ -7,7 +7,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -58,6 +59,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![100.0, 100.0, 100.0], Point::origin());
 }

benchmarks3d/capsules3.rs

@@ -7,7 +7,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -59,6 +60,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![100.0, 100.0, 100.0], Point::origin());
 }

benchmarks3d/ccd3.rs

@@ -7,7 +7,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -73,6 +74,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![100.0, 100.0, 100.0], Point::origin());
 }

benchmarks3d/compound3.rs

@@ -7,7 +7,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -66,6 +67,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![100.0, 100.0, 100.0], Point::origin());
 }

benchmarks3d/convex_polyhedron3.rs

@@ -9,7 +9,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -73,6 +74,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![100.0, 100.0, 100.0], Point::origin());
 }

benchmarks3d/heightfield3.rs

@@ -8,7 +8,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -73,6 +74,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![100.0, 100.0, 100.0], Point::origin());
 }

benchmarks3d/joint_ball3.rs

@@ -7,7 +7,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let mut joints = JointSet::new();
+    let mut impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     let rad = 0.4;
     let num = 100;
@@ -36,16 +37,16 @@ pub fn init_world(testbed: &mut Testbed) {
             // Vertical joint.
             if i > 0 {
                 let parent_handle = *body_handles.last().unwrap();
-                let joint = BallJoint::new(Point::origin(), point![0.0, 0.0, -shift]);
-                joints.insert(parent_handle, child_handle, joint);
+                let joint = SphericalJoint::new().local_anchor2(point![0.0, 0.0, -shift]);
+                impulse_joints.insert(parent_handle, child_handle, joint);
             }
 
             // Horizontal joint.
             if k > 0 {
                 let parent_index = body_handles.len() - num;
                 let parent_handle = body_handles[parent_index];
-                let joint = BallJoint::new(Point::origin(), point![-shift, 0.0, 0.0]);
-                joints.insert(parent_handle, child_handle, joint);
+                let joint = SphericalJoint::new().local_anchor2(point![-shift, 0.0, 0.0]);
+                impulse_joints.insert(parent_handle, child_handle, joint);
             }
 
             body_handles.push(child_handle);
@@ -55,6 +56,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![-110.0, -46.0, 170.0], point![54.0, -38.0, 29.0]);
 }

benchmarks3d/joint_fixed3.rs

@@ -7,7 +7,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let mut joints = JointSet::new();
+    let mut impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     let rad = 0.4;
     let num = 5;
@@ -49,22 +50,16 @@ pub fn init_world(testbed: &mut Testbed) {
                         // Vertical joint.
                         if i > 0 {
                             let parent_handle = *body_handles.last().unwrap();
-                            let joint = FixedJoint::new(
-                                Isometry::identity(),
-                                Isometry::translation(0.0, 0.0, -shift),
-                            );
-                            joints.insert(parent_handle, child_handle, joint);
+                            let joint = FixedJoint::new().local_anchor2(point![0.0, 0.0, -shift]);
+                            impulse_joints.insert(parent_handle, child_handle, joint);
                         }
 
                         // Horizontal joint.
                         if k > 0 {
                             let parent_index = body_handles.len() - num;
                             let parent_handle = body_handles[parent_index];
-                            let joint = FixedJoint::new(
-                                Isometry::identity(),
-                                Isometry::translation(-shift, 0.0, 0.0),
-                            );
-                            joints.insert(parent_handle, child_handle, joint);
+                            let joint = FixedJoint::new().local_anchor2(point![-shift, 0.0, 0.0]);
+                            impulse_joints.insert(parent_handle, child_handle, joint);
                         }
 
                         body_handles.push(child_handle);
@@ -77,6 +72,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![-38.0, 14.0, 108.0], point![46.0, 12.0, 23.0]);
 }

benchmarks3d/joint_prismatic3.rs

@@ -7,7 +7,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let mut joints = JointSet::new();
+    let mut impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     let rad = 0.4;
     let num = 5;
@@ -47,19 +48,10 @@ pub fn init_world(testbed: &mut Testbed) {
                         UnitVector::new_normalize(vector![-1.0, 1.0, 0.0])
                     };
 
-                    let z = Vector::z();
-                    let mut prism = PrismaticJoint::new(
-                        Point::origin(),
-                        axis,
-                        z,
-                        point![0.0, 0.0, -shift],
-                        axis,
-                        z,
-                    );
-                    prism.limits_enabled = true;
-                    prism.limits[0] = -2.0;
-                    prism.limits[1] = 2.0;
-                    joints.insert(curr_parent, curr_child, prism);
+                    let prism = PrismaticJoint::new(axis)
+                        .local_anchor2(point![0.0, 0.0, -shift])
+                        .limit_axis([-2.0, 0.0]);
+                    impulse_joints.insert(curr_parent, curr_child, prism);
 
                     curr_parent = curr_child;
                 }
@@ -70,6 +62,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![262.0, 63.0, 124.0], point![101.0, 4.0, -3.0]);
 }

benchmarks3d/joint_revolute3.rs

@@ -7,7 +7,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let mut joints = JointSet::new();
+    let mut impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     let rad = 0.4;
     let num = 10;
@@ -49,22 +50,21 @@ pub fn init_world(testbed: &mut Testbed) {
                     colliders.insert_with_parent(collider, handles[k], &mut bodies);
                 }
 
-                // Setup four joints.
-                let o = Point::origin();
+                // Setup four impulse_joints.
                 let x = Vector::x_axis();
                 let z = Vector::z_axis();
 
                 let revs = [
-                    RevoluteJoint::new(o, z, point![0.0, 0.0, -shift], z),
-                    RevoluteJoint::new(o, x, point![-shift, 0.0, 0.0], x),
-                    RevoluteJoint::new(o, z, point![0.0, 0.0, -shift], z),
-                    RevoluteJoint::new(o, x, point![shift, 0.0, 0.0], x),
+                    RevoluteJoint::new(z).local_anchor2(point![0.0, 0.0, -shift]),
+                    RevoluteJoint::new(x).local_anchor2(point![-shift, 0.0, 0.0]),
+                    RevoluteJoint::new(z).local_anchor2(point![0.0, 0.0, -shift]),
+                    RevoluteJoint::new(x).local_anchor2(point![shift, 0.0, 0.0]),
                 ];
 
-                joints.insert(curr_parent, handles[0], revs[0]);
-                joints.insert(handles[0], handles[1], revs[1]);
-                joints.insert(handles[1], handles[2], revs[2]);
-                joints.insert(handles[2], handles[3], revs[3]);
+                impulse_joints.insert(curr_parent, handles[0], revs[0]);
+                impulse_joints.insert(handles[0], handles[1], revs[1]);
+                impulse_joints.insert(handles[1], handles[2], revs[2]);
+                impulse_joints.insert(handles[2], handles[3], revs[3]);
 
                 curr_parent = handles[3];
             }
@@ -74,6 +74,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![478.0, 83.0, 228.0], point![134.0, 83.0, -116.0]);
 }

benchmarks3d/keva3.rs

@@ -83,7 +83,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -132,6 +133,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![100.0, 100.0, 100.0], Point::origin());
 }

benchmarks3d/pyramid3.rs

@@ -41,7 +41,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -73,6 +74,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![100.0, 100.0, 100.0], Point::origin());
 }

benchmarks3d/stacks3.rs

@@ -101,7 +101,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -183,6 +184,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![100.0, 100.0, 100.0], Point::origin());
 }

benchmarks3d/trimesh3.rs

@@ -8,7 +8,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -78,6 +79,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![100.0, 100.0, 100.0], Point::origin());
 }

crates/rapier2d-f64/Cargo.toml

@@ -8,9 +8,9 @@ homepage = "http://rapier.rs"
 repository = "https://github.com/dimforge/rapier"
 readme = "README.md"
 categories = [ "science", "game-development", "mathematics", "simulation", "wasm"]
-keywords = [ "physics", "dynamics", "rigid", "real-time", "joints" ]
+keywords = [ "physics", "dynamics", "rigid", "real-time", "impulse_joints" ]
 license = "Apache-2.0"
-edition = "2018"
+edition = "2021"
 
 [badges]
 maintenance = { status = "actively-developed" }
@@ -47,9 +47,9 @@ required-features = [ "dim2", "f64" ]
 vec_map = { version = "0.8", optional = true }
 instant = { version = "0.1", features = [ "now" ]}
 num-traits = "0.2"
-nalgebra = "0.29"
-parry2d-f64 = "^0.7.1"
-simba = "0.6"
+nalgebra = "0.30"
+parry2d-f64 = "0.8"
+simba = "0.7"
 approx = "0.5"
 rayon = { version = "1", optional = true }
 crossbeam = "0.8"

crates/rapier2d/Cargo.toml

@@ -8,9 +8,9 @@ homepage = "http://rapier.rs"
 repository = "https://github.com/dimforge/rapier"
 readme = "README.md"
 categories = [ "science", "game-development", "mathematics", "simulation", "wasm"]
-keywords = [ "physics", "dynamics", "rigid", "real-time", "joints" ]
+keywords = [ "physics", "dynamics", "rigid", "real-time", "impulse_joints" ]
 license = "Apache-2.0"
-edition = "2018"
+edition = "2021"
 
 [badges]
 maintenance = { status = "actively-developed" }
@@ -47,9 +47,9 @@ required-features = [ "dim2", "f32" ]
 vec_map = { version = "0.8", optional = true }
 instant = { version = "0.1", features = [ "now" ]}
 num-traits = "0.2"
-nalgebra = "0.29"
-parry2d = "^0.7.1"
-simba = "0.6"
+nalgebra = "0.30"
+parry2d = "0.8"
+simba = "0.7"
 approx = "0.5"
 rayon = { version = "1", optional = true }
 crossbeam = "0.8"

crates/rapier3d-f64/Cargo.toml

@@ -8,9 +8,9 @@ homepage = "http://rapier.rs"
 repository = "https://github.com/dimforge/rapier"
 readme = "README.md"
 categories = [ "science", "game-development", "mathematics", "simulation", "wasm"]
-keywords = [ "physics", "dynamics", "rigid", "real-time", "joints" ]
+keywords = [ "physics", "dynamics", "rigid", "real-time", "impulse_joints" ]
 license = "Apache-2.0"
-edition = "2018"
+edition = "2021"
 
 [badges]
 maintenance = { status = "actively-developed" }
@@ -47,9 +47,9 @@ required-features = [ "dim3", "f64" ]
 vec_map = { version = "0.8", optional = true }
 instant = { version = "0.1", features = [ "now" ]}
 num-traits = "0.2"
-nalgebra = "0.29"
-parry3d-f64 = "^0.7.1"
-simba = "0.6"
+nalgebra = "0.30"
+parry3d-f64 = "0.8"
+simba = "0.7"
 approx = "0.5"
 rayon = { version = "1", optional = true }
 crossbeam = "0.8"

crates/rapier3d/Cargo.toml

@@ -8,9 +8,9 @@ homepage = "http://rapier.rs"
 repository = "https://github.com/dimforge/rapier"
 readme = "README.md"
 categories = [ "science", "game-development", "mathematics", "simulation", "wasm"]
-keywords = [ "physics", "dynamics", "rigid", "real-time", "joints" ]
+keywords = [ "physics", "dynamics", "rigid", "real-time", "impulse_joints" ]
 license = "Apache-2.0"
-edition = "2018"
+edition = "2021"
 
 [badges]
 maintenance = { status = "actively-developed" }
@@ -47,9 +47,9 @@ required-features = [ "dim3", "f32" ]
 vec_map = { version = "0.8", optional = true }
 instant = { version = "0.1", features = [ "now" ]}
 num-traits = "0.2"
-nalgebra = "0.29"
-parry3d = "^0.7.1"
-simba = "0.6"
+nalgebra = "0.30"
+parry3d = "0.8"
+simba = "0.7"
 approx = "0.5"
 rayon = { version = "1", optional = true }
 crossbeam = "0.8"

crates/rapier_testbed2d/Cargo.toml

@@ -6,9 +6,9 @@ description = "Testbed for the Rapier 2-dimensional physics engine in Rust."
 homepage = "http://rapier.org"
 repository = "https://github.com/dimforge/rapier"
 categories = [ "science", "game-development", "mathematics", "simulation", "wasm"]
-keywords = [ "physics", "dynamics", "rigid", "real-time", "joints" ]
+keywords = [ "physics", "dynamics", "rigid", "real-time", "impulse_joints" ]
 license = "Apache-2.0"
-edition = "2018"
+edition = "2021"
 
 [badges]
 maintenance = { status = "actively-developed" }
@@ -22,20 +22,18 @@ required-features = [ "dim2" ]
 default = [ "dim2" ]
 dim2 = [ ]
 parallel = [ "rapier2d/parallel", "num_cpus" ]
-other-backends = [ "wrapped2d", "nphysics2d", "ncollide2d" ]
+other-backends = [ "wrapped2d" ]
 
 
 [dependencies]
-nalgebra   = { version = "0.29", features = [ "rand" ] }
+nalgebra   = { version = "0.30", features = [ "rand" ] }
 rand       = "0.8"
 rand_pcg   = "0.3"
 instant    = { version = "0.1", features = [ "web-sys", "now" ]}
 bitflags   = "1"
 num_cpus   = { version = "1", optional = true }
 wrapped2d  = { version = "0.4", optional = true }
-parry2d = "0.7"
-ncollide2d = { version = "0.32", optional = true }
-nphysics2d = { version = "0.24", optional = true }
+parry2d = "0.8"
 crossbeam = "0.8"
 bincode = "1"
 Inflector  = "0.11"

crates/rapier_testbed3d/Cargo.toml

@@ -6,9 +6,9 @@ description = "Testbed for the Rapier 3-dimensional physics engine in Rust."
 homepage = "http://rapier.org"
 repository = "https://github.com/dimforge/rapier"
 categories = [ "science", "game-development", "mathematics", "simulation", "wasm"]
-keywords = [ "physics", "dynamics", "rigid", "real-time", "joints" ]
+keywords = [ "physics", "dynamics", "rigid", "real-time", "impulse_joints" ]
 license = "Apache-2.0"
-edition = "2018"
+edition = "2021"
 
 [badges]
 maintenance = { status = "actively-developed" }
@@ -22,19 +22,17 @@ required-features = [ "dim3" ]
 default = [ "dim3" ]
 dim3 = [ ]
 parallel = [ "rapier3d/parallel", "num_cpus" ]
-other-backends = [ "physx", "physx-sys", "glam", "nphysics3d", "ncollide3d" ]
+other-backends = [ "physx", "physx-sys", "glam" ]
 
 [dependencies]
-nalgebra   = { version = "0.29", features = [ "rand" ] }
+nalgebra   = { version = "0.30", features = [ "rand" ] }
 rand       = "0.8"
 rand_pcg   = "0.3"
 instant    = { version = "0.1", features = [ "web-sys", "now" ]}
 bitflags   = "1"
 glam       = { version = "0.12", optional = true }
 num_cpus   = { version = "1", optional = true }
-parry3d    = "0.7"
-ncollide3d = { version = "0.32", optional = true }
-nphysics3d = { version = "0.24", optional = true }
+parry3d    = "0.8"
 physx      = { version = "0.11", optional = true }
 physx-sys = { version = "0.4", optional = true }
 crossbeam = "0.8"

examples2d/Cargo.toml

@@ -2,7 +2,7 @@
 name    = "rapier-examples-2d"
 version = "0.1.0"
 authors = [ "Sébastien Crozet <developer@crozet.re>" ]
-edition = "2018"
+edition = "2021"
 default-run = "all_examples2"
 
 [features]
@@ -19,10 +19,10 @@ lyon       = "0.17"
 usvg       = "0.14"
 
 [dependencies.rapier_testbed2d]
-path = "../build/rapier_testbed2d"
+path = "../crates/rapier_testbed2d"
 
 [dependencies.rapier2d]
-path = "../build/rapier2d"
+path = "../crates/rapier2d"
 
 [[bin]]
 name = "all_examples2"

examples2d/add_remove2.rs

@@ -4,12 +4,15 @@ use rapier_testbed2d::Testbed;
 pub fn init_world(testbed: &mut Testbed) {
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
+
     let rad = 0.5;
 
     let positions = [vector![5.0, -1.0], vector![-5.0, -1.0]];
 
-    let platform_handles = std::array::IntoIter::new(positions)
+    let platform_handles = positions
+        .into_iter()
         .map(|pos| {
             let rigid_body = RigidBodyBuilder::new_kinematic_position_based()
                 .translation(pos)
@@ -57,7 +60,8 @@ pub fn init_world(testbed: &mut Testbed) {
                 handle,
                 &mut physics.islands,
                 &mut physics.colliders,
-                &mut physics.joints,
+                &mut physics.impulse_joints,
+                &mut physics.multibody_joints,
             );
 
             if let Some(graphics) = &mut graphics {
@@ -69,6 +73,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![0.0, 0.0], 20.0);
 }

examples2d/ccd2.rs

@@ -7,7 +7,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -123,6 +124,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![0.0, 2.5], 20.0);
 }

examples2d/collision_groups2.rs

@@ -7,7 +7,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -89,6 +90,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![0.0, 1.0], 100.0);
 }

examples2d/convex_polygons2.rs

@@ -9,7 +9,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -76,6 +77,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![0.0, 50.0], 10.0);
 }

examples2d/damping2.rs

@@ -7,7 +7,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Create the balls
@@ -38,6 +39,13 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world_with_params(bodies, colliders, joints, Vector::zeros(), ());
+    testbed.set_world_with_params(
+        bodies,
+        colliders,
+        impulse_joints,
+        multibody_joints,
+        Vector::zeros(),
+        (),
+    );
     testbed.look_at(point![3.0, 2.0], 50.0);
 }

examples2d/debug_box_ball2.rs

@@ -7,7 +7,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -33,6 +34,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![0.0, 0.0], 50.0);
 }

examples2d/heightfield2.rs

@@ -8,7 +8,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -63,6 +64,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![0.0, 0.0], 10.0);
 }

examples2d/joints2.rs

@@ -7,7 +7,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let mut joints = JointSet::new();
+    let mut impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Create the balls
@@ -44,16 +45,16 @@ pub fn init_world(testbed: &mut Testbed) {
             // Vertical joint.
             if i > 0 {
                 let parent_handle = *body_handles.last().unwrap();
-                let joint = BallJoint::new(Point::origin(), point![0.0, shift]);
-                joints.insert(parent_handle, child_handle, joint);
+                let joint = RevoluteJoint::new().local_anchor2(point![0.0, shift]);
+                impulse_joints.insert(parent_handle, child_handle, joint);
             }
 
             // Horizontal joint.
             if k > 0 {
                 let parent_index = body_handles.len() - numi;
                 let parent_handle = body_handles[parent_index];
-                let joint = BallJoint::new(Point::origin(), point![-shift, 0.0]);
-                joints.insert(parent_handle, child_handle, joint);
+                let joint = RevoluteJoint::new().local_anchor2(point![-shift, 0.0]);
+                impulse_joints.insert(parent_handle, child_handle, joint);
             }
 
             body_handles.push(child_handle);
@@ -63,6 +64,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![numk as f32 * rad, numi as f32 * -rad], 20.0);
 }

examples2d/locked_rotations2.rs

@@ -10,7 +10,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * The ground
@@ -51,6 +52,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![0.0, 0.0], 40.0);
 }

examples2d/one_way_platforms2.rs

@@ -62,7 +62,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -126,7 +127,8 @@ pub fn init_world(testbed: &mut Testbed) {
     testbed.set_world_with_params(
         bodies,
         colliders,
-        joints,
+        impulse_joints,
+        multibody_joints,
         vector![0.0, -9.81],
         physics_hooks,
     );

examples2d/platform2.rs

@@ -7,7 +7,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground.
@@ -89,6 +90,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Run the simulation.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![0.0, 1.0], 40.0);
 }

examples2d/polyline2.rs

@@ -8,7 +8,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -65,6 +66,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![0.0, 0.0], 10.0);
 }

examples2d/pyramid2.rs

@@ -7,7 +7,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -50,6 +51,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![0.0, 2.5], 20.0);
 }

examples2d/restitution2.rs

@@ -7,7 +7,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -44,6 +45,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![0.0, 1.0], 25.0);
 }

examples2d/sensor2.rs

@@ -7,7 +7,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground.
@@ -98,6 +99,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![0.0, 1.0], 100.0);
 }

examples2d/trimesh2.rs

@@ -13,7 +13,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -103,7 +104,7 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![0.0, 20.0], 17.0);
 }
 

examples3d/Cargo.toml

@@ -2,7 +2,7 @@
 name    = "rapier-examples-3d"
 version = "0.1.0"
 authors = [ "Sébastien Crozet <developer@crozet.re>" ]
-edition = "2018"
+edition = "2021"
 default-run = "all_examples3"
 
 [features]
@@ -20,10 +20,10 @@ wasm-bindgen = "0.2"
 obj-rs = { version =  "0.6", default-features = false }
 
 [dependencies.rapier_testbed3d]
-path = "../build/rapier_testbed3d"
+path = "../crates/rapier_testbed3d"
 
 [dependencies.rapier3d]
-path = "../build/rapier3d"
+path = "../crates/rapier3d"
 
 [[bin]]
 name = "all_examples3"

examples3d/all_examples3.rs

@@ -8,6 +8,7 @@ use inflector::Inflector;
 use rapier_testbed3d::{Testbed, TestbedApp};
 use std::cmp::Ordering;
 
+mod articulations3;
 mod ccd3;
 mod collision_groups3;
 mod compound3;
@@ -15,6 +16,7 @@ mod convex_decomposition3;
 mod convex_polyhedron3;
 mod damping3;
 mod debug_add_remove_collider3;
+mod debug_articulations3;
 mod debug_big_colliders3;
 mod debug_boxes3;
 mod debug_cylinder3;
@@ -29,7 +31,7 @@ mod debug_trimesh3;
 mod domino3;
 mod fountain3;
 mod heightfield3;
-mod joints3;
+// mod joints3;
 mod keva3;
 mod locked_rotations3;
 mod one_way_platforms3;
@@ -78,6 +80,10 @@ pub fn main() {
     let mut builders: Vec<(_, fn(&mut Testbed))> = vec![
         ("Fountain", fountain3::init_world),
         ("Primitives", primitives3::init_world),
+        (
+            "Multibody joints",
+            articulations3::init_world_with_articulations,
+        ),
         ("CCD", ccd3::init_world),
         ("Collision groups", collision_groups3::init_world),
         ("Compound", compound3::init_world),
@@ -86,7 +92,7 @@ pub fn main() {
         ("Damping", damping3::init_world),
         ("Domino", domino3::init_world),
         ("Heightfield", heightfield3::init_world),
-        ("Joints", joints3::init_world),
+        ("Impulse Joints", articulations3::init_world_with_joints),
         ("Locked rotations", locked_rotations3::init_world),
         ("One-way platforms", one_way_platforms3::init_world),
         ("Platform", platform3::init_world),
@@ -94,6 +100,7 @@ pub fn main() {
         ("Sensor", sensor3::init_world),
         ("TriMesh", trimesh3::init_world),
         ("Keva tower", keva3::init_world),
+        ("(Debug) multibody_joints", debug_articulations3::init_world),
         (
             "(Debug) add/rm collider",
             debug_add_remove_collider3::init_world,

examples3d/articulations3.rs

@@ -0,0 +1,678 @@
+use rapier3d::prelude::*;
+use rapier_testbed3d::Testbed;
+
+fn create_prismatic_joints(
+    bodies: &mut RigidBodySet,
+    colliders: &mut ColliderSet,
+    impulse_joints: &mut ImpulseJointSet,
+    multibody_joints: &mut MultibodyJointSet,
+    origin: Point<f32>,
+    num: usize,
+    use_articulations: bool,
+) {
+    let rad = 0.4;
+    let shift = 2.0;
+
+    let ground = RigidBodyBuilder::new_static()
+        .translation(vector![origin.x, origin.y, origin.z])
+        .build();
+    let mut curr_parent = bodies.insert(ground);
+    let collider = ColliderBuilder::cuboid(rad, rad, rad).build();
+    colliders.insert_with_parent(collider, curr_parent, bodies);
+
+    for i in 0..num {
+        let z = origin.z + (i + 1) as f32 * shift;
+        let rigid_body = RigidBodyBuilder::new_dynamic()
+            .translation(vector![origin.x, origin.y, z])
+            .build();
+        let curr_child = bodies.insert(rigid_body);
+        let collider = ColliderBuilder::cuboid(rad, rad, rad).build();
+        colliders.insert_with_parent(collider, curr_child, bodies);
+
+        let axis = if i % 2 == 0 {
+            UnitVector::new_normalize(vector![1.0f32, 1.0, 0.0])
+        } else {
+            UnitVector::new_normalize(vector![-1.0f32, 1.0, 0.0])
+        };
+
+        let prism = PrismaticJoint::new(axis)
+            .local_anchor1(point![0.0, 0.0, 0.0])
+            .local_anchor2(point![0.0, 0.0, -shift])
+            .limit_axis([-2.0, 2.0]);
+
+        if use_articulations {
+            multibody_joints.insert(curr_parent, curr_child, prism);
+        } else {
+            impulse_joints.insert(curr_parent, curr_child, prism);
+        }
+        curr_parent = curr_child;
+    }
+}
+
+fn create_actuated_prismatic_joints(
+    bodies: &mut RigidBodySet,
+    colliders: &mut ColliderSet,
+    impulse_joints: &mut ImpulseJointSet,
+    multibody_joints: &mut MultibodyJointSet,
+    origin: Point<f32>,
+    num: usize,
+    use_articulations: bool,
+) {
+    let rad = 0.4;
+    let shift = 2.0;
+
+    let ground = RigidBodyBuilder::new_static()
+        .translation(vector![origin.x, origin.y, origin.z])
+        .build();
+    let mut curr_parent = bodies.insert(ground);
+    let collider = ColliderBuilder::cuboid(rad, rad, rad).build();
+    colliders.insert_with_parent(collider, curr_parent, bodies);
+
+    for i in 0..num {
+        let z = origin.z + (i + 1) as f32 * shift;
+        let rigid_body = RigidBodyBuilder::new_dynamic()
+            .translation(vector![origin.x, origin.y, z])
+            .build();
+        let curr_child = bodies.insert(rigid_body);
+        let collider = ColliderBuilder::cuboid(rad, rad, rad).build();
+        colliders.insert_with_parent(collider, curr_child, bodies);
+
+        let axis = if i % 2 == 0 {
+            UnitVector::new_normalize(vector![1.0, 1.0, 0.0])
+        } else {
+            UnitVector::new_normalize(vector![-1.0, 1.0, 0.0])
+        };
+
+        let mut prism = PrismaticJoint::new(axis)
+            .local_anchor1(point![0.0, 0.0, 0.0])
+            .local_anchor2(point![0.0, 0.0, -shift]);
+
+        if i == 1 {
+            prism = prism
+                .limit_axis([-Real::MAX, 5.0])
+                .motor_velocity(1.0, 1.0)
+                // We set a max impulse so that the motor doesn't fight
+                // the limits with large forces.
+                .motor_max_impulse(1.0);
+        } else if i > 1 {
+            prism = prism.motor_position(2.0, 0.01, 1.0);
+        } else {
+            prism = prism
+                .motor_velocity(1.0, 1.0)
+                // We set a max impulse so that the motor doesn't fight
+                // the limits with large forces.
+                .motor_max_impulse(0.7)
+                .limit_axis([-2.0, 5.0]);
+        }
+
+        if use_articulations {
+            multibody_joints.insert(curr_parent, curr_child, prism);
+        } else {
+            impulse_joints.insert(curr_parent, curr_child, prism);
+        }
+
+        curr_parent = curr_child;
+    }
+}
+
+fn create_revolute_joints(
+    bodies: &mut RigidBodySet,
+    colliders: &mut ColliderSet,
+    impulse_joints: &mut ImpulseJointSet,
+    multibody_joints: &mut MultibodyJointSet,
+    origin: Point<f32>,
+    num: usize,
+    use_articulations: bool,
+) {
+    let rad = 0.4;
+    let shift = 2.0;
+
+    let ground = RigidBodyBuilder::new_static()
+        .translation(vector![origin.x, origin.y, 0.0])
+        .build();
+    let mut curr_parent = bodies.insert(ground);
+    let collider = ColliderBuilder::cuboid(rad, rad, rad).build();
+    colliders.insert_with_parent(collider, curr_parent, bodies);
+
+    for i in 0..num {
+        // Create four bodies.
+        let z = origin.z + i as f32 * shift * 2.0 + shift;
+        let positions = [
+            Isometry::translation(origin.x, origin.y, z),
+            Isometry::translation(origin.x + shift, origin.y, z),
+            Isometry::translation(origin.x + shift, origin.y, z + shift),
+            Isometry::translation(origin.x, origin.y, z + shift),
+        ];
+
+        let mut handles = [curr_parent; 4];
+        for k in 0..4 {
+            let rigid_body = RigidBodyBuilder::new_dynamic()
+                .position(positions[k])
+                .build();
+            handles[k] = bodies.insert(rigid_body);
+            let collider = ColliderBuilder::cuboid(rad, rad, rad).build();
+            colliders.insert_with_parent(collider, handles[k], bodies);
+        }
+
+        // Setup four impulse_joints.
+        let x = Vector::x_axis();
+        let z = Vector::z_axis();
+        let revs = [
+            RevoluteJoint::new(z).local_anchor2(point![0.0, 0.0, -shift]),
+            RevoluteJoint::new(x).local_anchor2(point![-shift, 0.0, 0.0]),
+            RevoluteJoint::new(z).local_anchor2(point![0.0, 0.0, -shift]),
+            RevoluteJoint::new(x).local_anchor2(point![shift, 0.0, 0.0]),
+        ];
+
+        if use_articulations {
+            multibody_joints.insert(curr_parent, handles[0], revs[0]);
+            multibody_joints.insert(handles[0], handles[1], revs[1]);
+            multibody_joints.insert(handles[1], handles[2], revs[2]);
+            multibody_joints.insert(handles[2], handles[3], revs[3]);
+        } else {
+            impulse_joints.insert(curr_parent, handles[0], revs[0]);
+            impulse_joints.insert(handles[0], handles[1], revs[1]);
+            impulse_joints.insert(handles[1], handles[2], revs[2]);
+            impulse_joints.insert(handles[2], handles[3], revs[3]);
+        }
+
+        curr_parent = handles[3];
+    }
+}
+
+fn create_revolute_joints_with_limits(
+    bodies: &mut RigidBodySet,
+    colliders: &mut ColliderSet,
+    impulse_joints: &mut ImpulseJointSet,
+    multibody_joints: &mut MultibodyJointSet,
+    origin: Point<f32>,
+    use_articulations: bool,
+) {
+    let ground = bodies.insert(
+        RigidBodyBuilder::new_static()
+            .translation(origin.coords)
+            .build(),
+    );
+
+    let platform1 = bodies.insert(
+        RigidBodyBuilder::new_dynamic()
+            .translation(origin.coords)
+            .build(),
+    );
+    colliders.insert_with_parent(
+        ColliderBuilder::cuboid(4.0, 0.2, 2.0).build(),
+        platform1,
+        bodies,
+    );
+
+    let shift = vector![0.0, 0.0, 6.0];
+    let platform2 = bodies.insert(
+        RigidBodyBuilder::new_dynamic()
+            .translation(origin.coords + shift)
+            .build(),
+    );
+    colliders.insert_with_parent(
+        ColliderBuilder::cuboid(4.0, 0.2, 2.0).build(),
+        platform2,
+        bodies,
+    );
+
+    let z = Vector::z_axis();
+    let joint1 = RevoluteJoint::new(z).limit_axis([-0.2, 0.2]);
+
+    if use_articulations {
+        multibody_joints.insert(ground, platform1, joint1);
+    } else {
+        impulse_joints.insert(ground, platform1, joint1);
+    }
+
+    let joint2 = RevoluteJoint::new(z)
+        .local_anchor2(-Point::from(shift))
+        .limit_axis([-0.2, 0.2]);
+
+    if use_articulations {
+        multibody_joints.insert(platform1, platform2, joint2);
+    } else {
+        impulse_joints.insert(platform1, platform2, joint2);
+    }
+
+    // Let’s add a couple of cuboids that will fall on the platforms, triggering the joint limits.
+    let cuboid_body1 = bodies.insert(
+        RigidBodyBuilder::new_dynamic()
+            .translation(origin.coords + vector![-2.0, 4.0, 0.0])
+            .build(),
+    );
+    colliders.insert_with_parent(
+        ColliderBuilder::cuboid(0.6, 0.6, 0.6).friction(1.0).build(),
+        cuboid_body1,
+        bodies,
+    );
+
+    let cuboid_body2 = bodies.insert(
+        RigidBodyBuilder::new_dynamic()
+            .translation(origin.coords + shift + vector![2.0, 16.0, 0.0])
+            .build(),
+    );
+    colliders.insert_with_parent(
+        ColliderBuilder::cuboid(0.6, 0.6, 0.6).friction(1.0).build(),
+        cuboid_body2,
+        bodies,
+    );
+}
+
+fn create_fixed_joints(
+    bodies: &mut RigidBodySet,
+    colliders: &mut ColliderSet,
+    impulse_joints: &mut ImpulseJointSet,
+    multibody_joints: &mut MultibodyJointSet,
+    origin: Point<f32>,
+    num: usize,
+    use_articulations: bool,
+) {
+    let rad = 0.4;
+    let shift = 1.0;
+
+    let mut body_handles = Vec::new();
+
+    for i in 0..num {
+        for k in 0..num {
+            let fk = k as f32;
+            let fi = i as f32;
+
+            // NOTE: the num - 2 test is to avoid two consecutive
+            // fixed bodies. Because physx will crash if we add
+            // a joint between these.
+            let status = if i == 0 && (k % 4 == 0 && k != num - 2 || k == num - 1) {
+                RigidBodyType::Static
+            } else {
+                RigidBodyType::Dynamic
+            };
+
+            let rigid_body = RigidBodyBuilder::new(status)
+                .translation(vector![
+                    origin.x + fk * shift,
+                    origin.y,
+                    origin.z + fi * shift
+                ])
+                .build();
+            let child_handle = bodies.insert(rigid_body);
+            let collider = ColliderBuilder::ball(rad).build();
+            colliders.insert_with_parent(collider, child_handle, bodies);
+
+            // Vertical joint.
+            if i > 0 {
+                let parent_index = body_handles.len() - num;
+                let parent_handle = body_handles[parent_index];
+                let joint = FixedJoint::new().local_anchor2(point![0.0, 0.0, -shift]);
+
+                if use_articulations {
+                    multibody_joints.insert(parent_handle, child_handle, joint);
+                } else {
+                    impulse_joints.insert(parent_handle, child_handle, joint);
+                }
+            }
+
+            // Horizontal joint.
+            if k > 0 {
+                let parent_index = body_handles.len() - 1;
+                let parent_handle = body_handles[parent_index];
+                let joint = FixedJoint::new().local_anchor2(point![-shift, 0.0, 0.0]);
+                impulse_joints.insert(parent_handle, child_handle, joint);
+            }
+
+            body_handles.push(child_handle);
+        }
+    }
+}
+
+fn create_spherical_joints(
+    bodies: &mut RigidBodySet,
+    colliders: &mut ColliderSet,
+    impulse_joints: &mut ImpulseJointSet,
+    multibody_joints: &mut MultibodyJointSet,
+    num: usize,
+    use_articulations: bool,
+) {
+    let rad = 0.4;
+    let shift = 1.0;
+
+    let mut body_handles = Vec::new();
+
+    for k in 0..num {
+        for i in 0..num {
+            let fk = k as f32;
+            let fi = i as f32;
+
+            let status = if i == 0 && (k % 4 == 0 || k == num - 1) {
+                RigidBodyType::Static
+            } else {
+                RigidBodyType::Dynamic
+            };
+
+            let rigid_body = RigidBodyBuilder::new(status)
+                .translation(vector![fk * shift, 0.0, fi * shift * 2.0])
+                .build();
+            let child_handle = bodies.insert(rigid_body);
+            let collider = ColliderBuilder::capsule_z(rad * 1.25, rad).build();
+            colliders.insert_with_parent(collider, child_handle, bodies);
+
+            // Vertical joint.
+            if i > 0 {
+                let parent_handle = *body_handles.last().unwrap();
+                let joint = SphericalJoint::new().local_anchor2(point![0.0, 0.0, -shift * 2.0]);
+
+                if use_articulations {
+                    multibody_joints.insert(parent_handle, child_handle, joint);
+                } else {
+                    impulse_joints.insert(parent_handle, child_handle, joint);
+                }
+            }
+
+            // Horizontal joint.
+            if k > 0 {
+                let parent_index = body_handles.len() - num;
+                let parent_handle = body_handles[parent_index];
+                let joint = SphericalJoint::new().local_anchor2(point![-shift, 0.0, 0.0]);
+                impulse_joints.insert(parent_handle, child_handle, joint);
+            }
+
+            body_handles.push(child_handle);
+        }
+    }
+}
+
+fn create_spherical_joints_with_limits(
+    bodies: &mut RigidBodySet,
+    colliders: &mut ColliderSet,
+    impulse_joints: &mut ImpulseJointSet,
+    multibody_joints: &mut MultibodyJointSet,
+    origin: Point<f32>,
+    use_articulations: bool,
+) {
+    let shift = vector![0.0, 0.0, 3.0];
+
+    let ground = bodies.insert(
+        RigidBodyBuilder::new_static()
+            .translation(origin.coords)
+            .build(),
+    );
+
+    let ball1 = bodies.insert(
+        RigidBodyBuilder::new_dynamic()
+            .translation(origin.coords + shift)
+            .linvel(vector![20.0, 20.0, 0.0])
+            .build(),
+    );
+    colliders.insert_with_parent(
+        ColliderBuilder::cuboid(1.0, 1.0, 1.0).build(),
+        ball1,
+        bodies,
+    );
+
+    let ball2 = bodies.insert(
+        RigidBodyBuilder::new_dynamic()
+            .translation(origin.coords + shift * 2.0)
+            .build(),
+    );
+    colliders.insert_with_parent(
+        ColliderBuilder::cuboid(1.0, 1.0, 1.0).build(),
+        ball2,
+        bodies,
+    );
+
+    let joint1 = SphericalJoint::new()
+        .local_anchor2(Point::from(-shift))
+        .limit_axis(JointAxis::X, [-0.2, 0.2])
+        .limit_axis(JointAxis::Y, [-0.2, 0.2]);
+
+    let joint2 = SphericalJoint::new()
+        .local_anchor2(Point::from(-shift))
+        .limit_axis(JointAxis::X, [-0.3, 0.3])
+        .limit_axis(JointAxis::Y, [-0.3, 0.3]);
+
+    if use_articulations {
+        multibody_joints.insert(ground, ball1, joint1);
+        multibody_joints.insert(ball1, ball2, joint2);
+    } else {
+        impulse_joints.insert(ground, ball1, joint1);
+        impulse_joints.insert(ball1, ball2, joint2);
+    }
+}
+
+fn create_actuated_revolute_joints(
+    bodies: &mut RigidBodySet,
+    colliders: &mut ColliderSet,
+    impulse_joints: &mut ImpulseJointSet,
+    multibody_joints: &mut MultibodyJointSet,
+    origin: Point<f32>,
+    num: usize,
+    use_articulations: bool,
+) {
+    let rad = 0.4;
+    let shift = 2.0;
+
+    // We will reuse this base configuration for all the impulse_joints here.
+    let z = Vector::z_axis();
+    let joint_template = RevoluteJoint::new(z).local_anchor2(point![0.0, 0.0, -shift]);
+
+    let mut parent_handle = RigidBodyHandle::invalid();
+
+    for i in 0..num {
+        let fi = i as f32;
+
+        // NOTE: the num - 2 test is to avoid two consecutive
+        // fixed bodies. Because physx will crash if we add
+        // a joint between these.
+        let status = if i == 0 {
+            RigidBodyType::Static
+        } else {
+            RigidBodyType::Dynamic
+        };
+
+        let shifty = (i >= 1) as u32 as f32 * -2.0;
+
+        let rigid_body = RigidBodyBuilder::new(status)
+            .translation(vector![origin.x, origin.y + shifty, origin.z + fi * shift])
+            // .rotation(Vector3::new(0.0, fi * 1.1, 0.0))
+            .build();
+
+        let child_handle = bodies.insert(rigid_body);
+        let collider = ColliderBuilder::cuboid(rad * 2.0, rad * 6.0 / (fi + 1.0), rad).build();
+        colliders.insert_with_parent(collider, child_handle, bodies);
+
+        if i > 0 {
+            let mut joint = joint_template.clone();
+
+            if i % 3 == 1 {
+                joint = joint.motor_velocity(-20.0, 0.1);
+            } else if i == num - 1 {
+                let stiffness = 0.2;
+                let damping = 1.0;
+                joint = joint.motor_position(3.14 / 2.0, stiffness, damping);
+            }
+
+            if i == 1 {
+                joint = joint
+                    .local_anchor2(point![0.0, 2.0, -shift])
+                    .motor_velocity(-2.0, 0.1);
+            }
+
+            if use_articulations {
+                multibody_joints.insert(parent_handle, child_handle, joint);
+            } else {
+                impulse_joints.insert(parent_handle, child_handle, joint);
+            }
+        }
+
+        parent_handle = child_handle;
+    }
+}
+
+fn create_actuated_spherical_joints(
+    bodies: &mut RigidBodySet,
+    colliders: &mut ColliderSet,
+    impulse_joints: &mut ImpulseJointSet,
+    multibody_joints: &mut MultibodyJointSet,
+    origin: Point<f32>,
+    num: usize,
+    use_articulations: bool,
+) {
+    let rad = 0.4;
+    let shift = 2.0;
+
+    // We will reuse this base configuration for all the impulse_joints here.
+    let joint_template = SphericalJoint::new().local_anchor1(point![0.0, 0.0, shift]);
+
+    let mut parent_handle = RigidBodyHandle::invalid();
+
+    for i in 0..num {
+        let fi = i as f32;
+
+        // NOTE: the num - 2 test is to avoid two consecutive
+        // fixed bodies. Because physx will crash if we add
+        // a joint between these.
+        let status = if i == 0 {
+            RigidBodyType::Static
+        } else {
+            RigidBodyType::Dynamic
+        };
+
+        let rigid_body = RigidBodyBuilder::new(status)
+            .translation(vector![origin.x, origin.y, origin.z + fi * shift])
+            // .rotation(Vector3::new(0.0, fi * 1.1, 0.0))
+            .build();
+
+        let child_handle = bodies.insert(rigid_body);
+        let collider = ColliderBuilder::capsule_y(rad * 2.0 / (fi + 1.0), rad).build();
+        colliders.insert_with_parent(collider, child_handle, bodies);
+
+        if i > 0 {
+            let mut joint = joint_template.clone();
+
+            if i == 1 {
+                joint = joint
+                    .motor_velocity(JointAxis::AngX, 0.0, 0.1)
+                    .motor_velocity(JointAxis::AngY, 0.5, 0.1)
+                    .motor_velocity(JointAxis::AngZ, -2.0, 0.1);
+            } else if i == num - 1 {
+                let stiffness = 0.2;
+                let damping = 1.0;
+                joint = joint
+                    .motor_position(JointAxis::AngX, 0.0, stiffness, damping)
+                    .motor_position(JointAxis::AngY, 1.0, stiffness, damping)
+                    .motor_position(JointAxis::AngZ, 3.14 / 2.0, stiffness, damping);
+            }
+
+            if use_articulations {
+                multibody_joints.insert(parent_handle, child_handle, joint);
+            } else {
+                impulse_joints.insert(parent_handle, child_handle, joint);
+            }
+        }
+
+        parent_handle = child_handle;
+    }
+}
+
+fn do_init_world(testbed: &mut Testbed, use_articulations: bool) {
+    /*
+     * World
+     */
+    let mut bodies = RigidBodySet::new();
+    let mut colliders = ColliderSet::new();
+    let mut impulse_joints = ImpulseJointSet::new();
+    let mut multibody_joints = MultibodyJointSet::new();
+
+    create_prismatic_joints(
+        &mut bodies,
+        &mut colliders,
+        &mut impulse_joints,
+        &mut multibody_joints,
+        point![20.0, 5.0, 0.0],
+        4,
+        use_articulations,
+    );
+    create_actuated_prismatic_joints(
+        &mut bodies,
+        &mut colliders,
+        &mut impulse_joints,
+        &mut multibody_joints,
+        point![25.0, 5.0, 0.0],
+        4,
+        use_articulations,
+    );
+    create_revolute_joints(
+        &mut bodies,
+        &mut colliders,
+        &mut impulse_joints,
+        &mut multibody_joints,
+        point![20.0, 0.0, 0.0],
+        3,
+        use_articulations,
+    );
+    create_revolute_joints_with_limits(
+        &mut bodies,
+        &mut colliders,
+        &mut impulse_joints,
+        &mut multibody_joints,
+        point![34.0, 0.0, 0.0],
+        use_articulations,
+    );
+    create_fixed_joints(
+        &mut bodies,
+        &mut colliders,
+        &mut impulse_joints,
+        &mut multibody_joints,
+        point![0.0, 10.0, 0.0],
+        10,
+        use_articulations,
+    );
+    create_actuated_revolute_joints(
+        &mut bodies,
+        &mut colliders,
+        &mut impulse_joints,
+        &mut multibody_joints,
+        point![20.0, 10.0, 0.0],
+        6,
+        use_articulations,
+    );
+    create_actuated_spherical_joints(
+        &mut bodies,
+        &mut colliders,
+        &mut impulse_joints,
+        &mut multibody_joints,
+        point![13.0, 10.0, 0.0],
+        3,
+        use_articulations,
+    );
+    create_spherical_joints(
+        &mut bodies,
+        &mut colliders,
+        &mut impulse_joints,
+        &mut multibody_joints,
+        15,
+        use_articulations,
+    );
+    create_spherical_joints_with_limits(
+        &mut bodies,
+        &mut colliders,
+        &mut impulse_joints,
+        &mut multibody_joints,
+        point![-5.0, 0.0, 0.0],
+        use_articulations,
+    );
+
+    /*
+     * Set up the testbed.
+     */
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
+    testbed.look_at(point![15.0, 5.0, 42.0], point![13.0, 1.0, 1.0]);
+}
+
+pub fn init_world_with_joints(testbed: &mut Testbed) {
+    do_init_world(testbed, false)
+}
+
+pub fn init_world_with_articulations(testbed: &mut Testbed) {
+    do_init_world(testbed, true)
+}

examples3d/ccd3.rs

@@ -44,7 +44,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -153,6 +154,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![100.0, 100.0, 100.0], Point::origin());
 }

examples3d/collision_groups3.rs

@@ -7,7 +7,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -93,6 +94,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point!(10.0, 10.0, 10.0), Point::origin());
 }

examples3d/compound3.rs

@@ -7,7 +7,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -90,6 +91,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![100.0, 100.0, 100.0], Point::origin());
 }

examples3d/convex_decomposition3.rs

@@ -15,7 +15,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -52,7 +53,6 @@ pub fn init_world(testbed: &mut Testbed) {
                 .iter()
                 .map(|v| point![v.0, v.1, v.2])
                 .collect();
-            use std::iter::FromIterator;
             let indices: Vec<_> = model
                 .polygons
                 .into_iter()
@@ -104,7 +104,7 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![100.0, 100.0, 100.0], Point::origin());
 }
 

examples3d/convex_polyhedron3.rs

@@ -9,7 +9,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -68,6 +69,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![30.0, 30.0, 30.0], Point::origin());
 }

examples3d/damping3.rs

@@ -7,7 +7,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Create the cubes
@@ -38,6 +39,13 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world_with_params(bodies, colliders, joints, Vector::zeros(), ());
+    testbed.set_world_with_params(
+        bodies,
+        colliders,
+        impulse_joints,
+        multibody_joints,
+        Vector::zeros(),
+        (),
+    );
     testbed.look_at(point![2.0, 2.5, 20.0], point![2.0, 2.5, 0.0]);
 }

examples3d/debug_add_remove_collider3.rs

@@ -7,7 +7,9 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
+
     /*
      * Ground.
      */
@@ -54,6 +56,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![10.0, 10.0, 10.0], Point::origin());
 }

examples3d/debug_articulations3.rs

@@ -0,0 +1,98 @@
+use rapier3d::prelude::*;
+use rapier_testbed3d::Testbed;
+
+fn create_ball_articulations(
+    bodies: &mut RigidBodySet,
+    colliders: &mut ColliderSet,
+    impulse_joints: &mut ImpulseJointSet,
+    multibody_joints: &mut MultibodyJointSet,
+    num: usize,
+) {
+    let rad = 0.4;
+    let shift = 1.0;
+
+    let mut body_handles = Vec::new();
+
+    for k in 0..num {
+        for i in 0..num {
+            let fk = k as f32;
+            let fi = i as f32;
+
+            let status = if i == 0 {
+                // && (k % 4 == 0 || k == num - 1) {
+                RigidBodyType::Static
+            } else {
+                RigidBodyType::Dynamic
+            };
+
+            let rigid_body = RigidBodyBuilder::new(status)
+                .translation(vector![fk * shift, 0.0, fi * shift * 2.0])
+                .build();
+            let child_handle = bodies.insert(rigid_body);
+            let collider = ColliderBuilder::capsule_z(rad * 1.25, rad).build();
+            colliders.insert_with_parent(collider, child_handle, bodies);
+
+            // Vertical multibody_joint.
+            if i > 0 {
+                let parent_handle = *body_handles.last().unwrap();
+                let joint = SphericalJoint::new().local_anchor2(point![0.0, 0.0, -shift * 2.0]);
+                multibody_joints.insert(parent_handle, child_handle, joint);
+            }
+
+            // Horizontal multibody_joint.
+            if k > 0 && i > 0 {
+                let parent_index = body_handles.len() - num;
+                let parent_handle = body_handles[parent_index];
+                let joint = SphericalJoint::new().local_anchor2(point![-shift, 0.0, 0.0]);
+                // let joint =
+                //     PrismaticJoint::new(Vector::y_axis()).local_anchor2(point![-shift, 0.0, 0.0]);
+                // let joint = FixedJoint::new().local_anchor2(point![-shift, 0.0, 0.0]);
+                // let joint =
+                //     RevoluteJoint::new(Vector::x_axis()).local_anchor2(point![-shift, 0.0, 0.0]);
+                impulse_joints.insert(parent_handle, child_handle, joint);
+            }
+
+            body_handles.push(child_handle);
+        }
+    }
+}
+
+pub fn init_world(testbed: &mut Testbed) {
+    /*
+     * World
+     */
+    let mut bodies = RigidBodySet::new();
+    let mut colliders = ColliderSet::new();
+    let mut impulse_joints = ImpulseJointSet::new();
+    let mut multibody_joints = MultibodyJointSet::new();
+
+    let rigid_body = RigidBodyBuilder::new_dynamic().build();
+    let collider = ColliderBuilder::cuboid(30.0, 0.01, 30.0) // Vector::y_axis())
+        .translation(vector![0.0, -3.0, 0.0])
+        .rotation(vector![0.1, 0.0, 0.1])
+        .build();
+    let handle = bodies.insert(rigid_body);
+    colliders.insert_with_parent(collider, handle, &mut bodies);
+
+    let rigid_body = RigidBodyBuilder::new_static().build();
+    let collider = ColliderBuilder::cuboid(30.0, 0.01, 30.0) // Vector::y_axis())
+        .translation(vector![0.0, -3.02, 0.0])
+        .rotation(vector![0.1, 0.0, 0.1])
+        .build();
+    let handle = bodies.insert(rigid_body);
+    colliders.insert_with_parent(collider, handle, &mut bodies);
+
+    create_ball_articulations(
+        &mut bodies,
+        &mut colliders,
+        &mut impulse_joints,
+        &mut multibody_joints,
+        15,
+    );
+
+    /*
+     * Set up the testbed.
+     */
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
+    testbed.look_at(point![15.0, 5.0, 42.0], point![13.0, 1.0, 1.0]);
+}

examples3d/debug_big_colliders3.rs

@@ -7,7 +7,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -38,6 +39,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![10.0, 10.0, 10.0], Point::origin());
 }

examples3d/debug_boxes3.rs

@@ -7,7 +7,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -25,10 +26,10 @@ pub fn init_world(testbed: &mut Testbed) {
     }
 
     // Build the dynamic box rigid body.
-    for _ in 0..6 {
+    for _ in 0..2 {
         let rigid_body = RigidBodyBuilder::new_dynamic()
             .translation(vector![1.1, 0.0, 0.0])
-            .rotation(vector![0.8, 0.2, 0.1])
+            // .rotation(vector![0.8, 0.2, 0.1])
             .can_sleep(false)
             .build();
         let handle = bodies.insert(rigid_body);
@@ -39,6 +40,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![10.0, 10.0, 10.0], Point::origin());
 }

examples3d/debug_cylinder3.rs

@@ -10,7 +10,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -55,6 +56,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![100.0, 100.0, 100.0], Point::origin());
 }

examples3d/debug_dynamic_collider_add3.rs

@@ -7,7 +7,9 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
+
     /*
      * Ground.
      */
@@ -114,6 +116,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![10.0, 10.0, 10.0], Point::origin());
 }

examples3d/debug_friction3.rs

@@ -7,7 +7,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -38,6 +39,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![100.0, 100.0, 100.0], Point::origin());
 }

examples3d/debug_infinite_fall3.rs

@@ -7,7 +7,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -44,5 +45,5 @@ pub fn init_world(testbed: &mut Testbed) {
      * Set up the testbed.
      */
     testbed.look_at(point![100.0, -10.0, 100.0], Point::origin());
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
 }

examples3d/debug_prismatic3.rs

@@ -4,7 +4,7 @@ use rapier_testbed3d::Testbed;
 fn prismatic_repro(
     bodies: &mut RigidBodySet,
     colliders: &mut ColliderSet,
-    joints: &mut JointSet,
+    impulse_joints: &mut ImpulseJointSet,
     box_center: Point<f32>,
 ) {
     let box_rb = bodies.insert(
@@ -39,19 +39,12 @@ fn prismatic_repro(
         );
         colliders.insert_with_parent(ColliderBuilder::ball(0.5).build(), wheel_rb, bodies);
 
-        let mut prismatic = rapier3d::dynamics::PrismaticJoint::new(
-            point![pos.x, pos.y, pos.z],
-            Vector::y_axis(),
-            Vector::zeros(),
-            Point::origin(),
-            Vector::y_axis(),
-            Vector::default(),
-        );
-        prismatic.configure_motor_model(rapier3d::dynamics::SpringModel::VelocityBased);
         let (stiffness, damping) = (0.05, 0.2);
-        prismatic.configure_motor_position(0.0, stiffness, damping);
 
-        joints.insert(box_rb, wheel_rb, prismatic);
+        let prismatic = PrismaticJoint::new(Vector::y_axis())
+            .local_anchor1(point![pos.x, pos.y, pos.z])
+            .motor_position(0.0, stiffness, damping);
+        impulse_joints.insert(box_rb, wheel_rb, prismatic);
     }
 
     // put a small box under one of the wheels
@@ -73,7 +66,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let mut joints = JointSet::new();
+    let mut impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -91,13 +85,13 @@ pub fn init_world(testbed: &mut Testbed) {
     prismatic_repro(
         &mut bodies,
         &mut colliders,
-        &mut joints,
+        &mut impulse_joints,
         point![0.0, 5.0, 0.0],
     );
 
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![10.0, 10.0, 10.0], Point::origin());
 }

examples3d/debug_rollback3.rs

@@ -7,7 +7,9 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
+
     /*
      * Ground.
      */
@@ -65,6 +67,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![10.0, 10.0, 10.0], Point::origin());
 }

examples3d/debug_shape_modification3.rs

@@ -7,7 +7,9 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
+
     /*
      * Ground.
      */
@@ -113,6 +115,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![10.0, 10.0, 10.0], Point::origin());
 }

examples3d/debug_triangle3.rs

@@ -7,7 +7,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     // Triangle ground.
     let vtx = [
@@ -36,6 +37,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![10.0, 10.0, 10.0], Point::origin());
 }

examples3d/debug_trimesh3.rs

@@ -7,7 +7,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     // Triangle ground.
     let width = 0.5;
@@ -57,6 +58,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![10.0, 10.0, 10.0], Point::origin());
 }

examples3d/domino3.rs

@@ -7,7 +7,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -73,6 +74,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![100.0, 100.0, 100.0], Point::origin());
 }

examples3d/fountain3.rs

@@ -6,7 +6,9 @@ const MAX_NUMBER_OF_BODIES: usize = 400;
 pub fn init_world(testbed: &mut Testbed) {
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
+
     let rad = 0.5;
 
     /*
@@ -63,7 +65,8 @@ pub fn init_world(testbed: &mut Testbed) {
                     *handle,
                     &mut physics.islands,
                     &mut physics.colliders,
-                    &mut physics.joints,
+                    &mut physics.impulse_joints,
+                    &mut physics.multibody_joints,
                 );
 
                 if let Some(graphics) = &mut graphics {
@@ -76,10 +79,10 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     // testbed
     //     .physics_state_mut()
     //     .integration_parameters
-    //     .velocity_based_erp = 0.2;
+    //     .erp = 0.2;
     testbed.look_at(point![-30.0, 4.0, -30.0], point![0.0, 1.0, 0.0]);
 }

examples3d/harness_capsules3.rs

@@ -7,7 +7,8 @@ pub fn init_world(harness: &mut Harness) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -59,7 +60,7 @@ pub fn init_world(harness: &mut Harness) {
     /*
      * Set up the harness.
      */
-    harness.set_world(bodies, colliders, joints);
+    harness.set_world(bodies, colliders, impulse_joints, multibody_joints);
 }
 
 fn main() {

examples3d/heightfield3.rs

@@ -8,7 +8,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -95,6 +96,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![100.0, 100.0, 100.0], Point::origin());
 }

examples3d/joints3.rs

@@ -4,7 +4,7 @@ use rapier_testbed3d::Testbed;
 fn create_prismatic_joints(
     bodies: &mut RigidBodySet,
     colliders: &mut ColliderSet,
-    joints: &mut JointSet,
+    impulse_joints: &mut ImpulseJointSet,
     origin: Point<f32>,
     num: usize,
 ) {
@@ -28,25 +28,17 @@ fn create_prismatic_joints(
         colliders.insert_with_parent(collider, curr_child, bodies);
 
         let axis = if i % 2 == 0 {
-            UnitVector::new_normalize(vector![1.0, 1.0, 0.0])
+            UnitVector::new_normalize(vector![1.0f32, 1.0, 0.0])
         } else {
-            UnitVector::new_normalize(vector![-1.0, 1.0, 0.0])
+            UnitVector::new_normalize(vector![-1.0f32, 1.0, 0.0])
         };
 
-        let z = Vector::z();
-        let mut prism = PrismaticJoint::new(
-            point![0.0, 0.0, 0.0],
-            axis,
-            z,
-            point![0.0, 0.0, -shift],
-            axis,
-            z,
-        );
-        prism.limits_enabled = true;
-        prism.limits[0] = -2.0;
-        prism.limits[1] = 2.0;
+        let mut prism = JointData::prismatic(axis)
+            .local_anchor1(point![0.0, 0.0, shift])
+            .local_anchor2(point![0.0, 0.0, 0.0])
+            .limit_axis(JointAxis::X, [-2.0, 2.0]);
 
-        joints.insert(curr_parent, curr_child, prism);
+        impulse_joints.insert(curr_parent, curr_child, prism);
 
         curr_parent = curr_child;
     }
@@ -55,7 +47,7 @@ fn create_prismatic_joints(
 fn create_actuated_prismatic_joints(
     bodies: &mut RigidBodySet,
     colliders: &mut ColliderSet,
-    joints: &mut JointSet,
+    impulse_joints: &mut ImpulseJointSet,
     origin: Point<f32>,
     num: usize,
 ) {
@@ -84,36 +76,29 @@ fn create_actuated_prismatic_joints(
             UnitVector::new_normalize(vector![-1.0, 1.0, 0.0])
         };
 
-        let z = Vector::z();
-        let mut prism = PrismaticJoint::new(
-            point![0.0, 0.0, 0.0],
-            axis,
-            z,
-            point![0.0, 0.0, -shift],
-            axis,
-            z,
-        );
+        let mut prism = JointData::prismatic(axis)
+            .local_anchor1(point![0.0, 0.0, 0.0])
+            .local_anchor2(point![0.0, 0.0, -shift]);
 
         if i == 1 {
-            prism.configure_motor_velocity(1.0, 1.0);
-            prism.limits_enabled = true;
-            prism.limits[1] = 5.0;
-            // We set a max impulse so that the motor doesn't fight
-            // the limits with large forces.
-            prism.motor_max_impulse = 1.0;
+            prism = prism
+                .limit_axis(JointAxis::X, [-Real::MAX, 5.0])
+                .motor_velocity(JointAxis::X, 1.0, 1.0)
+                // We set a max impulse so that the motor doesn't fight
+                // the limits with large forces.
+                .motor_max_impulse(JointAxis::X, 1.0);
         } else if i > 1 {
-            prism.configure_motor_position(2.0, 0.01, 1.0);
+            prism = prism.motor_position(JointAxis::X, 2.0, 0.01, 1.0);
         } else {
-            prism.configure_motor_velocity(1.0, 1.0);
-            // We set a max impulse so that the motor doesn't fight
-            // the limits with large forces.
-            prism.motor_max_impulse = 0.7;
-            prism.limits_enabled = true;
-            prism.limits[0] = -2.0;
-            prism.limits[1] = 5.0;
+            prism = prism
+                .motor_velocity(JointAxis::X, 1.0, 1.0)
+                // We set a max impulse so that the motor doesn't fight
+                // the limits with large forces.
+                .motor_max_impulse(JointAxis::X, 0.7)
+                .limit_axis(JointAxis::X, [-2.0, 5.0]);
         }
 
-        joints.insert(curr_parent, curr_child, prism);
+        impulse_joints.insert(curr_parent, curr_child, prism);
 
         curr_parent = curr_child;
     }
@@ -122,7 +107,7 @@ fn create_actuated_prismatic_joints(
 fn create_revolute_joints(
     bodies: &mut RigidBodySet,
     colliders: &mut ColliderSet,
-    joints: &mut JointSet,
+    impulse_joints: &mut ImpulseJointSet,
     origin: Point<f32>,
     num: usize,
 ) {
@@ -156,22 +141,20 @@ fn create_revolute_joints(
             colliders.insert_with_parent(collider, handles[k], bodies);
         }
 
-        // Setup four joints.
-        let o = Point::origin();
+        // Setup four impulse_joints.
         let x = Vector::x_axis();
         let z = Vector::z_axis();
-
         let revs = [
-            RevoluteJoint::new(o, z, point![0.0, 0.0, -shift], z),
-            RevoluteJoint::new(o, x, point![-shift, 0.0, 0.0], x),
-            RevoluteJoint::new(o, z, point![0.0, 0.0, -shift], z),
-            RevoluteJoint::new(o, x, point![shift, 0.0, 0.0], x),
+            RevoluteJoint::new(x).local_anchor2(point![0.0, 0.0, -shift]),
+            RevoluteJoint::new(z).local_anchor2(point![-shift, 0.0, 0.0]),
+            RevoluteJoint::new(x).local_anchor2(point![0.0, 0.0, -shift]),
+            RevoluteJoint::new(z).local_anchor2(point![shift, 0.0, 0.0]),
         ];
 
-        joints.insert(curr_parent, handles[0], revs[0]);
-        joints.insert(handles[0], handles[1], revs[1]);
-        joints.insert(handles[1], handles[2], revs[2]);
-        joints.insert(handles[2], handles[3], revs[3]);
+        impulse_joints.insert(curr_parent, handles[0], revs[0]);
+        impulse_joints.insert(handles[0], handles[1], revs[1]);
+        impulse_joints.insert(handles[1], handles[2], revs[2]);
+        impulse_joints.insert(handles[2], handles[3], revs[3]);
 
         curr_parent = handles[3];
     }
@@ -180,7 +163,7 @@ fn create_revolute_joints(
 fn create_revolute_joints_with_limits(
     bodies: &mut RigidBodySet,
     colliders: &mut ColliderSet,
-    joints: &mut JointSet,
+    impulse_joints: &mut ImpulseJointSet,
     origin: Point<f32>,
 ) {
     let ground = bodies.insert(
@@ -212,25 +195,14 @@ fn create_revolute_joints_with_limits(
         bodies,
     );
 
-    let mut joint1 = RevoluteJoint::new(
-        Point::origin(),
-        Vector::z_axis(),
-        Point::origin(),
-        Vector::z_axis(),
-    );
-    joint1.limits_enabled = true;
-    joint1.limits = [-0.2, 0.2];
-    joints.insert(ground, platform1, joint1);
+    let z = Vector::z_axis();
+    let mut joint1 = RevoluteJoint::new(z).limit_axis(JointAxis::X, [-0.2, 0.2]);
+    impulse_joints.insert(ground, platform1, joint1);
 
-    let mut joint2 = RevoluteJoint::new(
-        Point::origin(),
-        Vector::z_axis(),
-        Point::from(-shift),
-        Vector::z_axis(),
-    );
-    joint2.limits_enabled = true;
-    joint2.limits = [-0.3, 0.3];
-    joints.insert(platform1, platform2, joint2);
+    let mut joint2 = RevoluteJoint::new(z)
+        .local_anchor2(shift.into())
+        .limit_axis(JointAxis::Z, [-0.2, 0.2]);
+    impulse_joints.insert(platform1, platform2, joint2);
 
     // Let’s add a couple of cuboids that will fall on the platforms, triggering the joint limits.
     let cuboid_body1 = bodies.insert(
@@ -259,7 +231,7 @@ fn create_revolute_joints_with_limits(
 fn create_fixed_joints(
     bodies: &mut RigidBodySet,
     colliders: &mut ColliderSet,
-    joints: &mut JointSet,
+    impulse_joints: &mut ImpulseJointSet,
     origin: Point<f32>,
     num: usize,
 ) {
@@ -268,8 +240,8 @@ fn create_fixed_joints(
 
     let mut body_handles = Vec::new();
 
-    for k in 0..num {
-        for i in 0..num {
+    for i in 0..num {
+        for k in 0..num {
             let fk = k as f32;
             let fi = i as f32;
 
@@ -295,23 +267,18 @@ fn create_fixed_joints(
 
             // Vertical joint.
             if i > 0 {
-                let parent_handle = *body_handles.last().unwrap();
-                let joint = FixedJoint::new(
-                    Isometry::identity(),
-                    Isometry::translation(0.0, 0.0, -shift),
-                );
-                joints.insert(parent_handle, child_handle, joint);
+                let parent_index = body_handles.len() - num;
+                let parent_handle = body_handles[parent_index];
+                let joint = JointData::fixed().local_anchor2(point![0.0, 0.0, -shift]);
+                impulse_joints.insert(parent_handle, child_handle, joint);
             }
 
             // Horizontal joint.
             if k > 0 {
-                let parent_index = body_handles.len() - num;
+                let parent_index = body_handles.len() - 1;
                 let parent_handle = body_handles[parent_index];
-                let joint = FixedJoint::new(
-                    Isometry::identity(),
-                    Isometry::translation(-shift, 0.0, 0.0),
-                );
-                joints.insert(parent_handle, child_handle, joint);
+                let joint = JointData::fixed().local_anchor2(point![-shift, 0.0, 0.0]);
+                impulse_joints.insert(parent_handle, child_handle, joint);
             }
 
             body_handles.push(child_handle);
@@ -322,7 +289,7 @@ fn create_fixed_joints(
 fn create_ball_joints(
     bodies: &mut RigidBodySet,
     colliders: &mut ColliderSet,
-    joints: &mut JointSet,
+    impulse_joints: &mut ImpulseJointSet,
     num: usize,
 ) {
     let rad = 0.4;
@@ -351,16 +318,16 @@ fn create_ball_joints(
             // Vertical joint.
             if i > 0 {
                 let parent_handle = *body_handles.last().unwrap();
-                let joint = BallJoint::new(Point::origin(), point![0.0, 0.0, -shift * 2.0]);
-                joints.insert(parent_handle, child_handle, joint);
+                let joint = JointData::ball().local_anchor2(point![0.0, 0.0, -shift * 2.0]);
+                impulse_joints.insert(parent_handle, child_handle, joint);
             }
 
             // Horizontal joint.
             if k > 0 {
                 let parent_index = body_handles.len() - num;
                 let parent_handle = body_handles[parent_index];
-                let joint = BallJoint::new(Point::origin(), point![-shift, 0.0, 0.0]);
-                joints.insert(parent_handle, child_handle, joint);
+                let joint = JointData::ball().local_anchor2(point![-shift, 0.0, 0.0]);
+                impulse_joints.insert(parent_handle, child_handle, joint);
             }
 
             body_handles.push(child_handle);
@@ -371,7 +338,7 @@ fn create_ball_joints(
 fn create_ball_joints_with_limits(
     bodies: &mut RigidBodySet,
     colliders: &mut ColliderSet,
-    joints: &mut JointSet,
+    impulse_joints: &mut ImpulseJointSet,
     origin: Point<f32>,
 ) {
     let shift = vector![0.0, 0.0, 3.0];
@@ -405,38 +372,32 @@ fn create_ball_joints_with_limits(
         bodies,
     );
 
-    let mut joint1 = BallJoint::new(Point::origin(), Point::from(-shift));
-    joint1.limits_enabled = true;
-    joint1.limits_local_axis1 = Vector::z_axis();
-    joint1.limits_local_axis2 = Vector::z_axis();
-    joint1.limits_angle = 0.2;
-    joints.insert(ground, ball1, joint1);
+    let mut joint1 = JointData::ball()
+        .local_anchor2(Point::from(-shift))
+        .limit_axis(JointAxis::X, [-0.2, 0.2])
+        .limit_axis(JointAxis::Y, [-0.2, 0.2]);
+    impulse_joints.insert(ground, ball1, joint1);
 
-    let mut joint2 = BallJoint::new(Point::origin(), Point::from(-shift));
-    joint2.limits_enabled = true;
-    joint2.limits_local_axis1 = Vector::z_axis();
-    joint2.limits_local_axis2 = Vector::z_axis();
-    joint2.limits_angle = 0.3;
-    joints.insert(ball1, ball2, joint2);
+    let mut joint2 = JointData::ball()
+        .local_anchor2(Point::from(-shift))
+        .limit_axis(JointAxis::X, [-0.3, 0.3])
+        .limit_axis(JointAxis::Y, [-0.3, 0.3]);
+    impulse_joints.insert(ball1, ball2, joint2);
 }
 
 fn create_actuated_revolute_joints(
     bodies: &mut RigidBodySet,
     colliders: &mut ColliderSet,
-    joints: &mut JointSet,
+    impulse_joints: &mut ImpulseJointSet,
     origin: Point<f32>,
     num: usize,
 ) {
     let rad = 0.4;
     let shift = 2.0;
 
-    // We will reuse this base configuration for all the joints here.
-    let joint_template = RevoluteJoint::new(
-        Point::origin(),
-        Vector::z_axis(),
-        point![0.0, 0.0, -shift],
-        Vector::z_axis(),
-    );
+    // We will reuse this base configuration for all the impulse_joints here.
+    let z = Vector::z_axis();
+    let joint_template = RevoluteJoint::new(z).local_anchor2(point![0.0, 0.0, -shift]);
 
     let mut parent_handle = RigidBodyHandle::invalid();
 
@@ -467,19 +428,19 @@ fn create_actuated_revolute_joints(
             let mut joint = joint_template.clone();
 
             if i % 3 == 1 {
-                joint.configure_motor_velocity(-20.0, 0.1);
+                joint = joint.motor_velocity(JointAxis::AngX, -20.0, 0.1);
             } else if i == num - 1 {
                 let stiffness = 0.2;
                 let damping = 1.0;
-                joint.configure_motor_position(3.14 / 2.0, stiffness, damping);
+                joint = joint.motor_position(JointAxis::AngX, 3.14 / 2.0, stiffness, damping);
             }
 
             if i == 1 {
-                joint.local_anchor2.y = 2.0;
-                joint.configure_motor_velocity(-2.0, 0.1);
+                joint.local_frame2.translation.vector.y = 2.0;
+                joint = joint.motor_velocity(JointAxis::AngX, -2.0, 0.1);
             }
 
-            joints.insert(parent_handle, child_handle, joint);
+            impulse_joints.insert(parent_handle, child_handle, joint);
         }
 
         parent_handle = child_handle;
@@ -489,15 +450,15 @@ fn create_actuated_revolute_joints(
 fn create_actuated_ball_joints(
     bodies: &mut RigidBodySet,
     colliders: &mut ColliderSet,
-    joints: &mut JointSet,
+    impulse_joints: &mut ImpulseJointSet,
     origin: Point<f32>,
     num: usize,
 ) {
     let rad = 0.4;
     let shift = 2.0;
 
-    // We will reuse this base configuration for all the joints here.
-    let joint_template = BallJoint::new(point![0.0, 0.0, shift], Point::origin());
+    // We will reuse this base configuration for all the impulse_joints here.
+    let joint_template = JointData::ball().local_anchor1(point![0.0, 0.0, shift]);
 
     let mut parent_handle = RigidBodyHandle::invalid();
 
@@ -526,18 +487,20 @@ fn create_actuated_ball_joints(
             let mut joint = joint_template.clone();
 
             if i == 1 {
-                joint.configure_motor_velocity(vector![0.0, 0.5, -2.0], 0.1);
+                joint = joint
+                    .motor_velocity(JointAxis::AngX, 0.0, 0.1)
+                    .motor_velocity(JointAxis::AngY, 0.5, 0.1)
+                    .motor_velocity(JointAxis::AngZ, -2.0, 0.1);
             } else if i == num - 1 {
                 let stiffness = 0.2;
                 let damping = 1.0;
-                joint.configure_motor_position(
-                    Rotation::new(vector![0.0, 1.0, 3.14 / 2.0]),
-                    stiffness,
-                    damping,
-                );
+                joint = joint
+                    .motor_position(JointAxis::AngX, 0.0, stiffness, damping)
+                    .motor_position(JointAxis::AngY, 1.0, stiffness, damping)
+                    .motor_position(JointAxis::AngZ, 3.14 / 2.0, stiffness, damping);
             }
 
-            joints.insert(parent_handle, child_handle, joint);
+            impulse_joints.insert(parent_handle, child_handle, joint);
         }
 
         parent_handle = child_handle;
@@ -550,67 +513,68 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let mut joints = JointSet::new();
+    let mut impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     create_prismatic_joints(
         &mut bodies,
         &mut colliders,
-        &mut joints,
+        &mut impulse_joints,
         point![20.0, 5.0, 0.0],
         4,
     );
     create_actuated_prismatic_joints(
         &mut bodies,
         &mut colliders,
-        &mut joints,
+        &mut impulse_joints,
         point![25.0, 5.0, 0.0],
         4,
     );
     create_revolute_joints(
         &mut bodies,
         &mut colliders,
-        &mut joints,
+        &mut impulse_joints,
         point![20.0, 0.0, 0.0],
         3,
     );
     create_revolute_joints_with_limits(
         &mut bodies,
         &mut colliders,
-        &mut joints,
+        &mut impulse_joints,
         point![34.0, 0.0, 0.0],
     );
     create_fixed_joints(
         &mut bodies,
         &mut colliders,
-        &mut joints,
+        &mut impulse_joints,
         point![0.0, 10.0, 0.0],
         10,
     );
     create_actuated_revolute_joints(
         &mut bodies,
         &mut colliders,
-        &mut joints,
+        &mut impulse_joints,
         point![20.0, 10.0, 0.0],
         6,
     );
     create_actuated_ball_joints(
         &mut bodies,
         &mut colliders,
-        &mut joints,
+        &mut impulse_joints,
         point![13.0, 10.0, 0.0],
         3,
     );
-    create_ball_joints(&mut bodies, &mut colliders, &mut joints, 15);
+    create_ball_joints(&mut bodies, &mut colliders, &mut impulse_joints, 15);
     create_ball_joints_with_limits(
         &mut bodies,
         &mut colliders,
-        &mut joints,
+        &mut impulse_joints,
         point![-5.0, 0.0, 0.0],
     );
 
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![15.0, 5.0, 42.0], point![13.0, 1.0, 1.0]);
 }

examples3d/keva3.rs

@@ -83,7 +83,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -132,6 +133,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![100.0, 100.0, 100.0], Point::origin());
 }

examples3d/locked_rotations3.rs

@@ -10,7 +10,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * The ground
@@ -54,6 +55,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![10.0, 3.0, 0.0], point![0.0, 3.0, 0.0]);
 }

examples3d/one_way_platforms3.rs

@@ -62,7 +62,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -126,7 +127,8 @@ pub fn init_world(testbed: &mut Testbed) {
     testbed.set_world_with_params(
         bodies,
         colliders,
-        joints,
+        impulse_joints,
+        multibody_joints,
         vector![0.0, -9.81, 0.0],
         physics_hooks,
     );

examples3d/platform3.rs

@@ -7,7 +7,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground.
@@ -103,6 +104,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Run the simulation.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![-10.0, 5.0, -10.0], Point::origin());
 }

examples3d/primitives3.rs

@@ -7,7 +7,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -51,13 +52,13 @@ pub fn init_world(testbed: &mut Testbed) {
                 let handle = bodies.insert(rigid_body);
 
                 let collider = match j % 5 {
-                    0 => ColliderBuilder::cuboid(rad, rad, rad).build(),
-                    1 => ColliderBuilder::ball(rad).build(),
-                    // Rounded cylinders are much more efficient that cylinder, even if the
-                    // rounding margin is small.
-                    2 => ColliderBuilder::round_cylinder(rad, rad, rad / 10.0).build(),
-                    3 => ColliderBuilder::cone(rad, rad).build(),
-                    _ => ColliderBuilder::capsule_y(rad, rad).build(),
+                    _ => ColliderBuilder::cuboid(rad, rad, rad).build(),
+                    // 1 => ColliderBuilder::ball(rad).build(),
+                    // // Rounded cylinders are much more efficient that cylinder, even if the
+                    // // rounding margin is small.
+                    // 2 => ColliderBuilder::round_cylinder(rad, rad, rad / 10.0).build(),
+                    // 3 => ColliderBuilder::cone(rad, rad).build(),
+                    // _ => ColliderBuilder::capsule_y(rad, rad).build(),
                 };
 
                 colliders.insert_with_parent(collider, handle, &mut bodies);
@@ -70,6 +71,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![100.0, 100.0, 100.0], Point::origin());
 }

examples3d/restitution3.rs

@@ -7,7 +7,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -44,6 +45,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![0.0, 3.0, 30.0], point![0.0, 3.0, 0.0]);
 }

examples3d/sensor3.rs

@@ -7,7 +7,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground.
@@ -102,6 +103,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![-6.0, 4.0, -6.0], point![0.0, 1.0, 0.0]);
 }

examples3d/trimesh3.rs

@@ -8,7 +8,8 @@ pub fn init_world(testbed: &mut Testbed) {
      */
     let mut bodies = RigidBodySet::new();
     let mut colliders = ColliderSet::new();
-    let joints = JointSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
 
     /*
      * Ground
@@ -100,6 +101,6 @@ pub fn init_world(testbed: &mut Testbed) {
     /*
      * Set up the testbed.
      */
-    testbed.set_world(bodies, colliders, joints);
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
     testbed.look_at(point![100.0, 100.0, 100.0], Point::origin());
 }

publish-testbeds.sh

@@ -6,20 +6,20 @@ echo "$tmp"
 
 cp -r src "$tmp"/.
 cp -r src_testbed "$tmp"/.
-cp -r build "$tmp"/.
+cp -r crates "$tmp"/.
 cp -r LICENSE README.md "$tmp"/.
 
 ### Publish the 2D version.
-sed 's#\.\./\.\./src#src#g' build/rapier_testbed2d/Cargo.toml > "$tmp"/Cargo.toml
-sed -i 's#\.\./rapier#./build/rapier#g' "$tmp"/Cargo.toml
+sed 's#\.\./\.\./src#src#g' crates/rapier_testbed2d/Cargo.toml > "$tmp"/Cargo.toml
+sed -i 's#\.\./rapier#./crates/rapier#g' "$tmp"/Cargo.toml
 currdir=$(pwd)
 cd "$tmp" && cargo publish
 cd "$currdir" || exit
 
 
 ### Publish the 3D version.
-sed 's#\.\./\.\./src#src#g' build/rapier_testbed3d/Cargo.toml > "$tmp"/Cargo.toml
-sed -i 's#\.\./rapier#./build/rapier#g' "$tmp"/Cargo.toml
+sed 's#\.\./\.\./src#src#g' crates/rapier_testbed3d/Cargo.toml > "$tmp"/Cargo.toml
+sed -i 's#\.\./rapier#./crates/rapier#g' "$tmp"/Cargo.toml
 cp -r LICENSE README.md "$tmp"/.
 cd "$tmp" && cargo publish
 

src/counters/mod.rs

@@ -14,7 +14,7 @@ mod solver_counters;
 mod stages_counters;
 mod timer;
 
-/// Aggregation of all the performances counters tracked by nphysics.
+/// Aggregation of all the performances counters tracked by rapier.
 #[derive(Clone, Copy)]
 pub struct Counters {
     /// Whether thi counter is enabled or not.
@@ -34,7 +34,7 @@ pub struct Counters {
 }
 
 impl Counters {
-    /// Create a new set of counters initialized to wero.
+    /// Create a new set of counters initialized to zero.
     pub fn new(enabled: bool) -> Self {
         Counters {
             enabled,

src/data/coarena.rs

@@ -13,6 +13,14 @@ impl<T> Coarena<T> {
         Self { data: Vec::new() }
     }
 
+    pub fn iter(&self) -> impl Iterator<Item = (Index, &T)> {
+        self.data
+            .iter()
+            .enumerate()
+            .filter(|(_, elt)| elt.0 != u32::MAX)
+            .map(|(i, elt)| (Index::from_raw_parts(i as u32, elt.0), &elt.1))
+    }
+
     /// Gets a specific element from the coarena without specifying its generation number.
     ///
     /// It is strongly encouraged to use `Coarena::get` instead of this method because this method
@@ -23,12 +31,12 @@ impl<T> Coarena<T> {
 
     /// Deletes an element for the coarena and returns its value.
     ///
-    /// We can't really remove an element from the coarena. So instead of actually removing
-    /// it, this method will reset the value to the given `removed_value`.
+    /// This method will reset the value to the given `removed_value`.
     pub fn remove(&mut self, index: Index, removed_value: T) -> Option<T> {
         let (i, g) = index.into_raw_parts();
         let data = self.data.get_mut(i as usize)?;
         if g == data.0 {
+            data.0 = u32::MAX; // invalidate the generation number.
             Some(std::mem::replace(&mut data.1, removed_value))
         } else {
             None

src/data/graph.rs

@@ -644,19 +644,24 @@ impl<'a, E> Iterator for Edges<'a, E> {
 
         // For iterate_over, "both" is represented as None.
         // For reverse, "no" is represented as None.
-        let (iterate_over, reverse) = (None, Some(self.direction.opposite()));
+        let (iterate_over, _reverse) = (None, Some(self.direction.opposite()));
 
         if iterate_over.unwrap_or(Direction::Outgoing) == Direction::Outgoing {
             let i = self.next[0].index();
-            if let Some(Edge { node, weight, next }) = self.edges.get(i) {
+            if let Some(Edge {
+                node: _node,
+                weight,
+                next,
+            }) = self.edges.get(i)
+            {
                 self.next[0] = next[0];
                 return Some(EdgeReference {
                     index: EdgeIndex(i as u32),
-                    node: if reverse == Some(Direction::Outgoing) {
-                        swap_pair(*node)
-                    } else {
-                        *node
-                    },
+                    // node: if reverse == Some(Direction::Outgoing) {
+                    //     swap_pair(*node)
+                    // } else {
+                    //     *node
+                    // },
                     weight,
                 });
             }
@@ -674,11 +679,11 @@ impl<'a, E> Iterator for Edges<'a, E> {
 
                 return Some(EdgeReference {
                     index: edge_index,
-                    node: if reverse == Some(Direction::Incoming) {
-                        swap_pair(*node)
-                    } else {
-                        *node
-                    },
+                    // node: if reverse == Some(Direction::Incoming) {
+                    //     swap_pair(*node)
+                    // } else {
+                    //     *node
+                    // },
                     weight,
                 });
             }
@@ -688,10 +693,10 @@ impl<'a, E> Iterator for Edges<'a, E> {
     }
 }
 
-fn swap_pair<T>(mut x: [T; 2]) -> [T; 2] {
-    x.swap(0, 1);
-    x
-}
+// fn swap_pair<T>(mut x: [T; 2]) -> [T; 2] {
+//     x.swap(0, 1);
+//     x
+// }
 
 impl<'a, E> Clone for Edges<'a, E> {
     fn clone(&self) -> Self {
@@ -742,24 +747,11 @@ impl<N, E> IndexMut<EdgeIndex> for Graph<N, E> {
     }
 }
 
-/// A “walker” object that can be used to step through the edge list of a node.
-///
-/// Created with [`.detach()`](struct.Neighbors.html#method.detach).
-///
-/// The walker does not borrow from the graph, so it lets you step through
-/// neighbors or incident edges while also mutating graph weights, as
-/// in the following example:
-#[derive(Clone)]
-pub struct WalkNeighbors {
-    skip_start: NodeIndex,
-    next: [EdgeIndex; 2],
-}
-
 /// Reference to a `Graph` edge.
 #[derive(Debug)]
 pub struct EdgeReference<'a, E: 'a> {
     index: EdgeIndex,
-    node: [NodeIndex; 2],
+    // node: [NodeIndex; 2],
     weight: &'a E,
 }
 

src/dynamics/integration_parameters.rs

@@ -18,18 +18,6 @@ pub struct IntegrationParameters {
     /// to numerical instabilities.
     pub min_ccd_dt: Real,
 
-    /// The Error Reduction Parameter in `[0, 1]` is the proportion of
-    /// the positional error to be corrected at each time step (default: `0.2`).
-    pub erp: Real,
-    /// The Error Reduction Parameter for joints in `[0, 1]` is the proportion of
-    /// the positional error to be corrected at each time step (default: `0.2`).
-    pub joint_erp: Real,
-    /// Each cached impulse are multiplied by this coefficient in `[0, 1]`
-    /// when they are re-used to initialize the solver (default `1.0`).
-    pub warmstart_coeff: Real,
-    /// Correction factor to avoid large warmstart impulse after a strong impact (default `10.0`).
-    pub warmstart_correction_slope: Real,
-
     /// 0-1: how much of the velocity to dampen out in the constraint solver?
     /// (default `1.0`).
     pub velocity_solve_fraction: Real,
@@ -40,23 +28,21 @@ pub struct IntegrationParameters {
     /// If non-zero, you do not need the positional solver.
     /// A good non-zero value is around `0.2`.
     /// (default `0.0`).
-    pub velocity_based_erp: Real,
+    pub erp: Real,
 
-    /// Amount of penetration the engine wont attempt to correct (default: `0.005m`).
+    /// Amount of penetration the engine wont attempt to correct (default: `0.001m`).
     pub allowed_linear_error: Real,
     /// The maximal distance separating two objects that will generate predictive contacts (default: `0.002`).
     pub prediction_distance: Real,
-    /// Amount of angular drift of joint limits the engine wont
-    /// attempt to correct (default: `0.001rad`).
-    pub allowed_angular_error: Real,
-    /// Maximum linear correction during one step of the non-linear position solver (default: `0.2`).
-    pub max_linear_correction: Real,
-    /// Maximum angular correction during one step of the non-linear position solver (default: `0.2`).
-    pub max_angular_correction: Real,
-    /// Maximum number of iterations performed by the velocity constraints solver (default: `4`).
+    /// Maximum number of iterations performed to solve non-penetration and joint constraints (default: `4`).
     pub max_velocity_iterations: usize,
-    /// Maximum number of iterations performed by the position-based constraints solver (default: `1`).
-    pub max_position_iterations: usize,
+    /// Maximum number of iterations performed to solve friction constraints (default: `8`).
+    pub max_velocity_friction_iterations: usize,
+    /// Maximum number of iterations performed to remove the energy introduced by penetration corrections  (default: `1`).
+    pub max_stabilization_iterations: usize,
+    /// If `false`, friction and non-penetration constraints will be solved in the same loop. Otherwise,
+    /// non-penetration constraints are solved first, and friction constraints are solved after (default: `true`).
+    pub interleave_restitution_and_friction_resolution: bool,
     /// Minimum number of dynamic bodies in each active island (default: `128`).
     pub min_island_size: usize,
     /// Maximum number of substeps performed by the  solver (default: `1`).
@@ -64,46 +50,6 @@ pub struct IntegrationParameters {
 }
 
 impl IntegrationParameters {
-    /// Creates a set of integration parameters with the given values.
-    #[deprecated = "Use `IntegrationParameters { dt: 60.0, ..Default::default() }` instead"]
-    pub fn new(
-        dt: Real,
-        erp: Real,
-        joint_erp: Real,
-        warmstart_coeff: Real,
-        allowed_linear_error: Real,
-        allowed_angular_error: Real,
-        max_linear_correction: Real,
-        max_angular_correction: Real,
-        prediction_distance: Real,
-        max_velocity_iterations: usize,
-        max_position_iterations: usize,
-        max_ccd_substeps: usize,
-    ) -> Self {
-        IntegrationParameters {
-            dt,
-            erp,
-            joint_erp,
-            warmstart_coeff,
-            allowed_linear_error,
-            allowed_angular_error,
-            max_linear_correction,
-            max_angular_correction,
-            prediction_distance,
-            max_velocity_iterations,
-            max_position_iterations,
-            max_ccd_substeps,
-            ..Default::default()
-        }
-    }
-
-    /// The current time-stepping length.
-    #[inline(always)]
-    #[deprecated = "You can just read the `IntegrationParams::dt` value directly"]
-    pub fn dt(&self) -> Real {
-        self.dt
-    }
-
     /// The inverse of the time-stepping length, i.e. the steps per seconds (Hz).
     ///
     /// This is zero if `self.dt` is zero.
@@ -136,10 +82,10 @@ impl IntegrationParameters {
         }
     }
 
-    /// Convenience: `velocity_based_erp / dt`
+    /// Convenience: `erp / dt`
     #[inline]
-    pub(crate) fn velocity_based_erp_inv_dt(&self) -> Real {
-        self.velocity_based_erp * self.inv_dt()
+    pub(crate) fn erp_inv_dt(&self) -> Real {
+        self.erp * self.inv_dt()
     }
 }
 
@@ -148,20 +94,14 @@ impl Default for IntegrationParameters {
         Self {
             dt: 1.0 / 60.0,
             min_ccd_dt: 1.0 / 60.0 / 100.0,
-            //        multithreading_enabled:             true,
-            erp: 0.2,
-            joint_erp: 0.2,
             velocity_solve_fraction: 1.0,
-            velocity_based_erp: 0.0,
-            warmstart_coeff: 1.0,
-            warmstart_correction_slope: 10.0,
-            allowed_linear_error: 0.005,
+            erp: 0.8,
+            allowed_linear_error: 0.001, // 0.005
             prediction_distance: 0.002,
-            allowed_angular_error: 0.001,
-            max_linear_correction: 0.2,
-            max_angular_correction: 0.2,
             max_velocity_iterations: 4,
-            max_position_iterations: 1,
+            max_velocity_friction_iterations: 8,
+            max_stabilization_iterations: 1,
+            interleave_restitution_and_friction_resolution: true, // Enabling this makes a big difference for 2D stability.
             // FIXME: what is the optimal value for min_island_size?
             // It should not be too big so that we don't end up with
             // huge islands that don't fit in cache.

src/dynamics/island_manager.rs

@@ -1,7 +1,7 @@
 use crate::data::{BundleSet, ComponentSet, ComponentSetMut, ComponentSetOption};
 use crate::dynamics::{
-    JointSet, RigidBodyActivation, RigidBodyColliders, RigidBodyHandle, RigidBodyIds,
-    RigidBodyType, RigidBodyVelocity,
+    ImpulseJointSet, MultibodyJointSet, RigidBodyActivation, RigidBodyColliders, RigidBodyHandle,
+    RigidBodyIds, RigidBodyType, RigidBodyVelocity,
 };
 use crate::geometry::{ColliderParent, NarrowPhase};
 use crate::math::Real;
@@ -175,7 +175,8 @@ impl IslandManager {
         bodies: &mut Bodies,
         colliders: &Colliders,
         narrow_phase: &NarrowPhase,
-        joints: &JointSet,
+        impulse_joints: &ImpulseJointSet,
+        multibody_joints: &MultibodyJointSet,
         min_island_size: usize,
     ) where
         Bodies: ComponentSetMut<RigidBodyIds>
@@ -302,11 +303,15 @@ impl IslandManager {
             // in contact or joined with this collider.
             push_contacting_bodies(rb_colliders, colliders, narrow_phase, &mut self.stack);
 
-            for inter in joints.joints_with(handle) {
+            for inter in impulse_joints.joints_with(handle) {
                 let other = crate::utils::select_other((inter.0, inter.1), handle);
                 self.stack.push(other);
             }
 
+            for other in multibody_joints.attached_bodies(handle) {
+                self.stack.push(other);
+            }
+
             bodies.map_mut_internal(handle.0, |activation: &mut RigidBodyActivation| {
                 activation.wake_up(false);
             });

src/dynamics/joint/ball_joint.rs

@@ -1,148 +0,0 @@
-use crate::dynamics::SpringModel;
-use crate::math::{Point, Real, Rotation, UnitVector, Vector};
-
-#[derive(Copy, Clone, PartialEq)]
-#[cfg_attr(feature = "serde-serialize", derive(Serialize, Deserialize))]
-/// A joint that removes all relative linear motion between a pair of points on two bodies.
-pub struct BallJoint {
-    /// Where the ball joint is attached on the first body, expressed in the first body local frame.
-    pub local_anchor1: Point<Real>,
-    /// Where the ball joint is attached on the second body, expressed in the second body local frame.
-    pub local_anchor2: Point<Real>,
-    /// The impulse applied by this joint on the first body.
-    ///
-    /// The impulse applied to the second body is given by `-impulse`.
-    pub impulse: Vector<Real>,
-
-    /// The target relative angular velocity the motor will attempt to reach.
-    #[cfg(feature = "dim2")]
-    pub motor_target_vel: Real,
-    /// The target relative angular velocity the motor will attempt to reach.
-    #[cfg(feature = "dim3")]
-    pub motor_target_vel: Vector<Real>,
-    /// The target angular position of this joint, expressed as an axis-angle.
-    pub motor_target_pos: Rotation<Real>,
-    /// The motor's stiffness.
-    /// See the documentation of `SpringModel` for more information on this parameter.
-    pub motor_stiffness: Real,
-    /// The motor's damping.
-    /// See the documentation of `SpringModel` for more information on this parameter.
-    pub motor_damping: Real,
-    /// The maximal impulse the motor is able to deliver.
-    pub motor_max_impulse: Real,
-    /// The angular impulse applied by the motor.
-    #[cfg(feature = "dim2")]
-    pub motor_impulse: Real,
-    /// The angular impulse applied by the motor.
-    #[cfg(feature = "dim3")]
-    pub motor_impulse: Vector<Real>,
-    /// The spring-like model used by the motor to reach the target velocity and .
-    pub motor_model: SpringModel,
-
-    /// Are the limits enabled for this joint?
-    pub limits_enabled: bool,
-    /// The axis of the limit cone for this joint, if the local-space of the first body.
-    pub limits_local_axis1: UnitVector<Real>,
-    /// The axis of the limit cone for this joint, if the local-space of the first body.
-    pub limits_local_axis2: UnitVector<Real>,
-    /// The maximum angle allowed between the two limit axes in world-space.
-    pub limits_angle: Real,
-    /// The impulse applied to enforce joint limits.
-    pub limits_impulse: Real,
-}
-
-impl BallJoint {
-    /// Creates a new Ball joint from two anchors given on the local spaces of the respective bodies.
-    pub fn new(local_anchor1: Point<Real>, local_anchor2: Point<Real>) -> Self {
-        Self::with_impulse(local_anchor1, local_anchor2, Vector::zeros())
-    }
-
-    pub(crate) fn with_impulse(
-        local_anchor1: Point<Real>,
-        local_anchor2: Point<Real>,
-        impulse: Vector<Real>,
-    ) -> Self {
-        Self {
-            local_anchor1,
-            local_anchor2,
-            impulse,
-            motor_target_vel: na::zero(),
-            motor_target_pos: Rotation::identity(),
-            motor_stiffness: 0.0,
-            motor_damping: 0.0,
-            motor_impulse: na::zero(),
-            motor_max_impulse: Real::MAX,
-            motor_model: SpringModel::default(),
-            limits_enabled: false,
-            limits_local_axis1: Vector::x_axis(),
-            limits_local_axis2: Vector::x_axis(),
-            limits_angle: Real::MAX,
-            limits_impulse: 0.0,
-        }
-    }
-
-    /// Can a SIMD constraint be used for resolving this joint?
-    pub fn supports_simd_constraints(&self) -> bool {
-        // SIMD ball constraints don't support motors and limits right now.
-        !self.limits_enabled
-            && (self.motor_max_impulse == 0.0
-                || (self.motor_stiffness == 0.0 && self.motor_damping == 0.0))
-    }
-
-    /// Set the spring-like model used by the motor to reach the desired target velocity and position.
-    pub fn configure_motor_model(&mut self, model: SpringModel) {
-        self.motor_model = model;
-    }
-
-    /// Sets the target velocity and velocity correction factor this motor.
-    #[cfg(feature = "dim2")]
-    pub fn configure_motor_velocity(&mut self, target_vel: Real, factor: Real) {
-        self.configure_motor(self.motor_target_pos, target_vel, 0.0, factor)
-    }
-
-    /// Sets the target velocity and velocity correction factor this motor.
-    #[cfg(feature = "dim3")]
-    pub fn configure_motor_velocity(&mut self, target_vel: Vector<Real>, factor: Real) {
-        self.configure_motor(self.motor_target_pos, target_vel, 0.0, factor)
-    }
-
-    /// Sets the target orientation this motor needs to reach.
-    pub fn configure_motor_position(
-        &mut self,
-        target_pos: Rotation<Real>,
-        stiffness: Real,
-        damping: Real,
-    ) {
-        self.configure_motor(target_pos, na::zero(), stiffness, damping)
-    }
-
-    /// Sets the target orientation this motor needs to reach.
-    #[cfg(feature = "dim2")]
-    pub fn configure_motor(
-        &mut self,
-        target_pos: Rotation<Real>,
-        target_vel: Real,
-        stiffness: Real,
-        damping: Real,
-    ) {
-        self.motor_target_vel = target_vel;
-        self.motor_target_pos = target_pos;
-        self.motor_stiffness = stiffness;
-        self.motor_damping = damping;
-    }
-
-    /// Configure both the target orientation and target velocity of the motor.
-    #[cfg(feature = "dim3")]
-    pub fn configure_motor(
-        &mut self,
-        target_pos: Rotation<Real>,
-        target_vel: Vector<Real>,
-        stiffness: Real,
-        damping: Real,
-    ) {
-        self.motor_target_vel = target_vel;
-        self.motor_target_pos = target_pos;
-        self.motor_stiffness = stiffness;
-        self.motor_damping = damping;
-    }
-}

src/dynamics/joint/fixed_joint.rs

@@ -1,38 +1,55 @@
-use crate::math::{Isometry, Real, SpacialVector};
+use crate::dynamics::{JointAxesMask, JointData};
+use crate::math::{Isometry, Point, Real};
 
-#[derive(Copy, Clone, PartialEq)]
 #[cfg_attr(feature = "serde-serialize", derive(Serialize, Deserialize))]
-/// A joint that prevents all relative movement between two bodies.
-///
-/// Given two frames of references, this joint aims to ensure these frame always coincide in world-space.
+#[derive(Copy, Clone, Debug, PartialEq)]
 pub struct FixedJoint {
-    /// The frame of reference for the first body affected by this joint, expressed in the local frame
-    /// of the first body.
-    pub local_frame1: Isometry<Real>,
-    /// The frame of reference for the second body affected by this joint, expressed in the local frame
-    /// of the first body.
-    pub local_frame2: Isometry<Real>,
-    /// The impulse applied to the first body affected by this joint.
-    ///
-    /// The impulse applied to the second body affected by this joint is given by `-impulse`.
-    /// This combines both linear and angular impulses:
-    /// - In 2D, `impulse.xy()` gives the linear impulse, and `impulse.z` the angular impulse.
-    /// - In 3D, `impulse.xyz()` gives the linear impulse, and `(impulse[3], impulse[4], impulse[5])` the angular impulse.
-    pub impulse: SpacialVector<Real>,
+    data: JointData,
 }
 
 impl FixedJoint {
-    /// Creates a new fixed joint from the frames of reference of both bodies.
-    pub fn new(local_frame1: Isometry<Real>, local_frame2: Isometry<Real>) -> Self {
-        Self {
-            local_frame1,
-            local_frame2,
-            impulse: SpacialVector::zeros(),
-        }
+    pub fn new() -> Self {
+        #[cfg(feature = "dim2")]
+        let mask = JointAxesMask::X | JointAxesMask::Y | JointAxesMask::ANG_X;
+        #[cfg(feature = "dim3")]
+        let mask = JointAxesMask::X
+            | JointAxesMask::Y
+            | JointAxesMask::Z
+            | JointAxesMask::ANG_X
+            | JointAxesMask::ANG_Y
+            | JointAxesMask::ANG_Z;
+
+        let data = JointData::default().lock_axes(mask);
+        Self { data }
     }
 
-    /// Can a SIMD constraint be used for resolving this joint?
-    pub fn supports_simd_constraints(&self) -> bool {
-        true
+    #[must_use]
+    pub fn local_frame1(mut self, local_frame: Isometry<Real>) -> Self {
+        self.data = self.data.local_frame1(local_frame);
+        self
+    }
+
+    #[must_use]
+    pub fn local_frame2(mut self, local_frame: Isometry<Real>) -> Self {
+        self.data = self.data.local_frame2(local_frame);
+        self
+    }
+
+    #[must_use]
+    pub fn local_anchor1(mut self, anchor1: Point<Real>) -> Self {
+        self.data = self.data.local_anchor1(anchor1);
+        self
+    }
+
+    #[must_use]
+    pub fn local_anchor2(mut self, anchor2: Point<Real>) -> Self {
+        self.data = self.data.local_anchor2(anchor2);
+        self
+    }
+}
+
+impl Into<JointData> for FixedJoint {
+    fn into(self) -> JointData {
+        self.data
     }
 }

src/dynamics/joint/generic_joint.rs

@@ -1,144 +0,0 @@
-use crate::dynamics::{BallJoint, FixedJoint, PrismaticJoint, RevoluteJoint};
-use crate::math::{Isometry, Real, SpacialVector};
-use crate::na::{Rotation3, UnitQuaternion};
-
-#[derive(Copy, Clone, Debug, PartialEq)]
-#[cfg_attr(feature = "serde-serialize", derive(Serialize, Deserialize))]
-/// A joint that prevents all relative movement between two bodies.
-///
-/// Given two frames of references, this joint aims to ensure these frame always coincide in world-space.
-pub struct GenericJoint {
-    /// The frame of reference for the first body affected by this joint, expressed in the local frame
-    /// of the first body.
-    pub local_anchor1: Isometry<Real>,
-    /// The frame of reference for the second body affected by this joint, expressed in the local frame
-    /// of the first body.
-    pub local_anchor2: Isometry<Real>,
-    /// The impulse applied to the first body affected by this joint.
-    ///
-    /// The impulse applied to the second body affected by this joint is given by `-impulse`.
-    /// This combines both linear and angular impulses:
-    /// - In 2D, `impulse.xy()` gives the linear impulse, and `impulse.z` the angular impulse.
-    /// - In 3D, `impulse.xyz()` gives the linear impulse, and `(impulse[3], impulse[4], impulse[5])` the angular impulse.
-    pub impulse: SpacialVector<Real>,
-
-    pub min_position: SpacialVector<Real>,
-    pub max_position: SpacialVector<Real>,
-    pub min_velocity: SpacialVector<Real>,
-    pub max_velocity: SpacialVector<Real>,
-    /// The minimum negative impulse the joint can apply on each DoF. Must be <= 0.0
-    pub min_impulse: SpacialVector<Real>,
-    /// The maximum positive impulse the joint can apply on each DoF. Must be >= 0.0
-    pub max_impulse: SpacialVector<Real>,
-    /// The minimum negative position impulse the joint can apply on each DoF. Must be <= 0.0
-    pub min_pos_impulse: SpacialVector<Real>,
-    /// The maximum positive position impulse the joint can apply on each DoF. Must be >= 0.0
-    pub max_pos_impulse: SpacialVector<Real>,
-}
-
-impl GenericJoint {
-    /// Creates a new fixed joint from the frames of reference of both bodies.
-    pub fn new(local_anchor1: Isometry<Real>, local_anchor2: Isometry<Real>) -> Self {
-        Self {
-            local_anchor1,
-            local_anchor2,
-            impulse: SpacialVector::zeros(),
-            min_position: SpacialVector::zeros(),
-            max_position: SpacialVector::zeros(),
-            min_velocity: SpacialVector::zeros(),
-            max_velocity: SpacialVector::zeros(),
-            min_impulse: SpacialVector::repeat(-Real::MAX),
-            max_impulse: SpacialVector::repeat(Real::MAX),
-            min_pos_impulse: SpacialVector::repeat(-Real::MAX),
-            max_pos_impulse: SpacialVector::repeat(Real::MAX),
-        }
-    }
-
-    pub fn set_dof_vel(&mut self, dof: u8, target_vel: Real, max_force: Real) {
-        self.min_velocity[dof as usize] = target_vel;
-        self.max_velocity[dof as usize] = target_vel;
-        self.min_impulse[dof as usize] = -max_force;
-        self.max_impulse[dof as usize] = max_force;
-    }
-
-    pub fn free_dof(&mut self, dof: u8) {
-        self.min_position[dof as usize] = -Real::MAX;
-        self.max_position[dof as usize] = Real::MAX;
-        self.min_velocity[dof as usize] = -Real::MAX;
-        self.max_velocity[dof as usize] = Real::MAX;
-        self.min_impulse[dof as usize] = 0.0;
-        self.max_impulse[dof as usize] = 0.0;
-        self.min_pos_impulse[dof as usize] = 0.0;
-        self.max_pos_impulse[dof as usize] = 0.0;
-    }
-
-    pub fn set_dof_limits(&mut self, dof: u8, min: Real, max: Real) {
-        self.min_position[dof as usize] = min;
-        self.max_position[dof as usize] = max;
-    }
-}
-
-impl From<RevoluteJoint> for GenericJoint {
-    fn from(joint: RevoluteJoint) -> Self {
-        let basis1 = [*joint.local_axis1, joint.basis1[0], joint.basis1[1]];
-        let basis2 = [*joint.local_axis2, joint.basis2[0], joint.basis2[1]];
-        let quat1 = UnitQuaternion::from_basis_unchecked(&basis1);
-        let quat2 = UnitQuaternion::from_basis_unchecked(&basis2);
-        let local_anchor1 = Isometry::from_parts(joint.local_anchor1.coords.into(), quat1);
-        let local_anchor2 = Isometry::from_parts(joint.local_anchor2.coords.into(), quat2);
-
-        let mut result = Self::new(local_anchor1, local_anchor2);
-        result.free_dof(3);
-
-        if joint.motor_damping != 0.0 {
-            result.set_dof_vel(3, joint.motor_target_vel, joint.motor_max_impulse);
-        }
-
-        result.impulse[0] = joint.impulse[0];
-        result.impulse[1] = joint.impulse[1];
-        result.impulse[2] = joint.impulse[2];
-        result.impulse[3] = joint.motor_impulse;
-        result.impulse[4] = joint.impulse[3];
-        result.impulse[5] = joint.impulse[4];
-
-        result
-    }
-}
-
-impl From<BallJoint> for GenericJoint {
-    fn from(joint: BallJoint) -> Self {
-        let local_anchor1 = Isometry::new(joint.local_anchor1.coords, na::zero());
-        let local_anchor2 = Isometry::new(joint.local_anchor2.coords, na::zero());
-
-        let mut result = Self::new(local_anchor1, local_anchor2);
-        result.impulse[0] = joint.impulse[0];
-        result.impulse[1] = joint.impulse[1];
-        result.impulse[2] = joint.impulse[2];
-        result.free_dof(3);
-        result.free_dof(4);
-        result.free_dof(5);
-        result
-    }
-}
-
-impl From<PrismaticJoint> for GenericJoint {
-    fn from(joint: PrismaticJoint) -> Self {
-        let basis1 = [*joint.local_axis1, joint.basis1[0], joint.basis1[1]];
-        let basis2 = [*joint.local_axis2, joint.basis2[0], joint.basis2[1]];
-        let quat1 = UnitQuaternion::from_basis_unchecked(&basis1);
-        let quat2 = UnitQuaternion::from_basis_unchecked(&basis2);
-        let local_anchor1 = Isometry::from_parts(joint.local_anchor1.coords.into(), quat1);
-        let local_anchor2 = Isometry::from_parts(joint.local_anchor2.coords.into(), quat2);
-
-        let mut result = Self::new(local_anchor1, local_anchor2);
-        result.free_dof(0);
-        result.set_dof_limits(0, joint.limits[0], joint.limits[1]);
-        result
-    }
-}
-
-impl From<FixedJoint> for GenericJoint {
-    fn from(joint: FixedJoint) -> Self {
-        Self::new(joint.local_anchor1, joint.local_anchor2)
-    }
-}

src/dynamics/joint/impulse_joint/impulse_joint.rs

@@ -0,0 +1,20 @@
+use crate::dynamics::{JointData, JointHandle, RigidBodyHandle};
+use crate::math::{Real, SpacialVector};
+
+#[cfg_attr(feature = "serde-serialize", derive(Serialize, Deserialize))]
+#[derive(Clone, Debug, PartialEq)]
+/// A joint attached to two bodies.
+pub struct ImpulseJoint {
+    /// Handle to the first body attached to this joint.
+    pub body1: RigidBodyHandle,
+    /// Handle to the second body attached to this joint.
+    pub body2: RigidBodyHandle,
+
+    pub data: JointData,
+    pub impulses: SpacialVector<Real>,
+
+    // A joint needs to know its handle to simplify its removal.
+    pub(crate) handle: JointHandle,
+    #[cfg(feature = "parallel")]
+    pub(crate) constraint_index: usize,
+}

src/dynamics/joint/impulse_joint/impulse_joint_set.rs

@@ -1,10 +1,10 @@
-use super::Joint;
+use super::ImpulseJoint;
 use crate::geometry::{InteractionGraph, RigidBodyGraphIndex, TemporaryInteractionIndex};
 
 use crate::data::arena::Arena;
 use crate::data::{BundleSet, Coarena, ComponentSet, ComponentSetMut};
 use crate::dynamics::{IslandManager, RigidBodyActivation, RigidBodyIds, RigidBodyType};
-use crate::dynamics::{JointParams, RigidBodyHandle};
+use crate::dynamics::{JointData, RigidBodyHandle};
 
 /// The unique identifier of a joint added to the joint set.
 /// The unique identifier of a collider added to a collider set.
@@ -34,19 +34,19 @@ impl JointHandle {
 }
 
 pub(crate) type JointIndex = usize;
-pub(crate) type JointGraphEdge = crate::data::graph::Edge<Joint>;
+pub(crate) type JointGraphEdge = crate::data::graph::Edge<ImpulseJoint>;
 
 #[cfg_attr(feature = "serde-serialize", derive(Serialize, Deserialize))]
 #[derive(Clone, Default)]
-/// A set of joints that can be handled by a physics `World`.
-pub struct JointSet {
+/// A set of impulse_joints that can be handled by a physics `World`.
+pub struct ImpulseJointSet {
     rb_graph_ids: Coarena<RigidBodyGraphIndex>,
     joint_ids: Arena<TemporaryInteractionIndex>, // Map joint handles to edge ids on the graph.
-    joint_graph: InteractionGraph<RigidBodyHandle, Joint>,
+    joint_graph: InteractionGraph<RigidBodyHandle, ImpulseJoint>,
 }
 
-impl JointSet {
-    /// Creates a new empty set of joints.
+impl ImpulseJointSet {
+    /// Creates a new empty set of impulse_joints.
     pub fn new() -> Self {
         Self {
             rb_graph_ids: Coarena::new(),
@@ -55,26 +55,26 @@ impl JointSet {
         }
     }
 
-    /// The number of joints on this set.
+    /// The number of impulse_joints on this set.
     pub fn len(&self) -> usize {
         self.joint_graph.graph.edges.len()
     }
 
-    /// `true` if there are no joints in this set.
+    /// `true` if there are no impulse_joints in this set.
     pub fn is_empty(&self) -> bool {
         self.joint_graph.graph.edges.is_empty()
     }
 
-    /// Retrieve the joint graph where edges are joints and nodes are rigid body handles.
-    pub fn joint_graph(&self) -> &InteractionGraph<RigidBodyHandle, Joint> {
+    /// Retrieve the joint graph where edges are impulse_joints and nodes are rigid body handles.
+    pub fn joint_graph(&self) -> &InteractionGraph<RigidBodyHandle, ImpulseJoint> {
         &self.joint_graph
     }
 
-    /// Iterates through all the joitns attached to the given rigid-body.
+    /// Iterates through all the impulse_joints attached to the given rigid-body.
     pub fn joints_with<'a>(
         &'a self,
         body: RigidBodyHandle,
-    ) -> impl Iterator<Item = (RigidBodyHandle, RigidBodyHandle, &'a Joint)> {
+    ) -> impl Iterator<Item = (RigidBodyHandle, RigidBodyHandle, &'a ImpulseJoint)> {
         self.rb_graph_ids
             .get(body.0)
             .into_iter()
@@ -87,13 +87,13 @@ impl JointSet {
     }
 
     /// Gets the joint with the given handle.
-    pub fn get(&self, handle: JointHandle) -> Option<&Joint> {
+    pub fn get(&self, handle: JointHandle) -> Option<&ImpulseJoint> {
         let id = self.joint_ids.get(handle.0)?;
         self.joint_graph.graph.edge_weight(*id)
     }
 
     /// Gets a mutable reference to the joint with the given handle.
-    pub fn get_mut(&mut self, handle: JointHandle) -> Option<&mut Joint> {
+    pub fn get_mut(&mut self, handle: JointHandle) -> Option<&mut ImpulseJoint> {
         let id = self.joint_ids.get(handle.0)?;
         self.joint_graph.graph.edge_weight_mut(*id)
     }
@@ -107,7 +107,7 @@ impl JointSet {
     ///
     /// Using this is discouraged in favor of `self.get(handle)` which does not
     /// suffer form the ABA problem.
-    pub fn get_unknown_gen(&self, i: u32) -> Option<(&Joint, JointHandle)> {
+    pub fn get_unknown_gen(&self, i: u32) -> Option<(&ImpulseJoint, JointHandle)> {
         let (id, handle) = self.joint_ids.get_unknown_gen(i)?;
         Some((
             self.joint_graph.graph.edge_weight(*id)?,
@@ -124,7 +124,7 @@ impl JointSet {
     ///
     /// Using this is discouraged in favor of `self.get_mut(handle)` which does not
     /// suffer form the ABA problem.
-    pub fn get_unknown_gen_mut(&mut self, i: u32) -> Option<(&mut Joint, JointHandle)> {
+    pub fn get_unknown_gen_mut(&mut self, i: u32) -> Option<(&mut ImpulseJoint, JointHandle)> {
         let (id, handle) = self.joint_ids.get_unknown_gen(i)?;
         Some((
             self.joint_graph.graph.edge_weight_mut(*id)?,
@@ -133,7 +133,7 @@ impl JointSet {
     }
 
     /// Iterates through all the joint on this set.
-    pub fn iter(&self) -> impl Iterator<Item = (JointHandle, &Joint)> {
+    pub fn iter(&self) -> impl Iterator<Item = (JointHandle, &ImpulseJoint)> {
         self.joint_graph
             .graph
             .edges
@@ -142,7 +142,7 @@ impl JointSet {
     }
 
     /// Iterates mutably through all the joint on this set.
-    pub fn iter_mut(&mut self) -> impl Iterator<Item = (JointHandle, &mut Joint)> {
+    pub fn iter_mut(&mut self) -> impl Iterator<Item = (JointHandle, &mut ImpulseJoint)> {
         self.joint_graph
             .graph
             .edges
@@ -150,8 +150,8 @@ impl JointSet {
             .map(|e| (e.weight.handle, &mut e.weight))
     }
 
-    // /// The set of joints as an array.
-    // pub(crate) fn joints(&self) -> &[JointGraphEdge] {
+    // /// The set of impulse_joints as an array.
+    // pub(crate) fn impulse_joints(&self) -> &[JointGraphEdge] {
     //     // self.joint_graph
     //     //     .graph
     //     //     .edges
@@ -170,25 +170,22 @@ impl JointSet {
     }
 
     /// Inserts a new joint into this set and retrieve its handle.
-    pub fn insert<J>(
+    pub fn insert(
         &mut self,
         body1: RigidBodyHandle,
         body2: RigidBodyHandle,
-        joint_params: J,
-    ) -> JointHandle
-    where
-        J: Into<JointParams>,
-    {
+        data: impl Into<JointData>,
+    ) -> JointHandle {
+        let data = data.into();
         let handle = self.joint_ids.insert(0.into());
-        let joint = Joint {
+        let joint = ImpulseJoint {
             body1,
             body2,
+            data,
+            impulses: na::zero(),
             handle: JointHandle(handle),
             #[cfg(feature = "parallel")]
             constraint_index: 0,
-            #[cfg(feature = "parallel")]
-            position_constraint_index: 0,
-            params: joint_params.into(),
         };
 
         let default_id = InteractionGraph::<(), ()>::invalid_graph_index();
@@ -201,12 +198,12 @@ impl JointSet {
 
         // NOTE: the body won't have a graph index if it does not
         // have any joint attached.
-        if !InteractionGraph::<RigidBodyHandle, Joint>::is_graph_index_valid(graph_index1) {
+        if !InteractionGraph::<RigidBodyHandle, ImpulseJoint>::is_graph_index_valid(graph_index1) {
             graph_index1 = self.joint_graph.graph.add_node(joint.body1);
             self.rb_graph_ids.insert(joint.body1.0, graph_index1);
         }
 
-        if !InteractionGraph::<RigidBodyHandle, Joint>::is_graph_index_valid(graph_index2) {
+        if !InteractionGraph::<RigidBodyHandle, ImpulseJoint>::is_graph_index_valid(graph_index2) {
             graph_index2 = self.joint_graph.graph.add_node(joint.body2);
             self.rb_graph_ids.insert(joint.body2.0, graph_index2);
         }
@@ -215,7 +212,7 @@ impl JointSet {
         JointHandle(handle)
     }
 
-    /// Retrieve all the joints happening between two active bodies.
+    /// Retrieve all the impulse_joints happening between two active bodies.
     // NOTE: this is very similar to the code from NarrowPhase::select_active_interactions.
     pub(crate) fn select_active_interactions<Bodies>(
         &self,
@@ -271,7 +268,7 @@ impl JointSet {
         islands: &mut IslandManager,
         bodies: &mut Bodies,
         wake_up: bool,
-    ) -> Option<Joint>
+    ) -> Option<ImpulseJoint>
     where
         Bodies: ComponentSetMut<RigidBodyActivation>
             + ComponentSet<RigidBodyType>
@@ -299,11 +296,11 @@ impl JointSet {
         removed_joint
     }
 
-    /// Deletes all the joints attached to the given rigid-body.
+    /// Deletes all the impulse_joints attached to the given rigid-body.
     ///
     /// The provided rigid-body handle is not required to identify a rigid-body that
     /// is still contained by the `bodies` component set.
-    /// Returns the (now invalid) handles of the removed joints.
+    /// Returns the (now invalid) handles of the removed impulse_joints.
     pub fn remove_joints_attached_to_rigid_body<Bodies>(
         &mut self,
         handle: RigidBodyHandle,

src/dynamics/joint/impulse_joint/mod.rs

@@ -0,0 +1,6 @@
+pub use self::impulse_joint::ImpulseJoint;
+pub use self::impulse_joint_set::{ImpulseJointSet, JointHandle};
+pub(crate) use self::impulse_joint_set::{JointGraphEdge, JointIndex};
+
+mod impulse_joint;
+mod impulse_joint_set;