feat: add a benchmark with many individual pyramids

benchmarks3d/many_pyramids3.rs

@@ -0,0 +1,80 @@
+use rapier3d::prelude::*;
+use rapier_testbed3d::Testbed;
+
+fn create_pyramid(
+    bodies: &mut RigidBodySet,
+    colliders: &mut ColliderSet,
+    offset: Vector<f32>,
+    stack_height: usize,
+    rad: f32,
+) {
+    let shift = rad * 2.0;
+
+    for i in 0usize..stack_height {
+        for j in i..stack_height {
+            let fj = j as f32;
+            let fi = i as f32;
+            let x = (fi * shift / 2.0) + (fj - fi) * shift;
+            let y = fi * shift;
+
+            // Build the rigid body.
+            let rigid_body = RigidBodyBuilder::dynamic().translation(vector![x, y, 0.0] + offset);
+            let handle = bodies.insert(rigid_body);
+            let collider = ColliderBuilder::cuboid(rad, rad, rad);
+            colliders.insert_with_parent(collider, handle, bodies);
+        }
+    }
+}
+
+pub fn init_world(testbed: &mut Testbed) {
+    /*
+     * World
+     */
+    let mut bodies = RigidBodySet::new();
+    let mut colliders = ColliderSet::new();
+    let impulse_joints = ImpulseJointSet::new();
+    let multibody_joints = MultibodyJointSet::new();
+
+    let rad = 0.5;
+    let pyramid_count = 40;
+    let spacing = 4.0;
+
+    /*
+     * Ground
+     */
+    let ground_size = 50.0;
+    let ground_height = 0.1;
+
+    let rigid_body = RigidBodyBuilder::fixed().translation(vector![0.0, -ground_height, 0.0]);
+    let ground_handle = bodies.insert(rigid_body);
+    let collider = ColliderBuilder::cuboid(
+        ground_size,
+        ground_height,
+        pyramid_count as f32 * spacing / 2.0 + ground_size,
+    );
+    colliders.insert_with_parent(collider, ground_handle, &mut bodies);
+
+    /*
+     * Create the cubes
+     */
+    for pyramid_index in 0..pyramid_count {
+        let bottomy = rad;
+        create_pyramid(
+            &mut bodies,
+            &mut colliders,
+            vector![
+                0.0,
+                bottomy,
+                (pyramid_index as f32 - pyramid_count as f32 / 2.0) * spacing
+            ],
+            20,
+            rad,
+        );
+    }
+
+    /*
+     * Set up the testbed.
+     */
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
+    testbed.look_at(point![100.0, 100.0, 100.0], Point::origin());
+}