Add collision groups demos.

examples2d/all_examples2.rs

@@ -11,6 +11,7 @@ use rapier_testbed2d::Testbed;
 use std::cmp::Ordering;
 
 mod add_remove2;
+mod collision_groups2;
 mod debug_box_ball2;
 mod heightfield2;
 mod joints2;
@@ -52,6 +53,7 @@ pub fn main() {
 
     let mut builders: Vec<(_, fn(&mut Testbed))> = vec![
         ("Add remove", add_remove2::init_world),
+        ("Collision groups", collision_groups2::init_world),
         ("Heightfield", heightfield2::init_world),
         ("Joints", joints2::init_world),
         ("Platform", platform2::init_world),

examples2d/collision_groups2.rs

@@ -0,0 +1,98 @@
+use na::{Point2, Point3};
+use rapier2d::dynamics::{JointSet, RigidBodyBuilder, RigidBodySet};
+use rapier2d::geometry::{ColliderBuilder, ColliderSet, InteractionGroups};
+use rapier_testbed2d::Testbed;
+
+pub fn init_world(testbed: &mut Testbed) {
+    /*
+     * World
+     */
+    let mut bodies = RigidBodySet::new();
+    let mut colliders = ColliderSet::new();
+    let joints = JointSet::new();
+
+    /*
+     * Ground
+     */
+    let ground_size = 5.0;
+    let ground_height = 0.1;
+
+    let rigid_body = RigidBodyBuilder::new_static()
+        .translation(0.0, -ground_height)
+        .build();
+    let floor_handle = bodies.insert(rigid_body);
+    let collider = ColliderBuilder::cuboid(ground_size, ground_height).build();
+    colliders.insert(collider, floor_handle, &mut bodies);
+
+    /*
+     * Setup groups
+     */
+    const GREEN_GROUP: InteractionGroups = InteractionGroups::new(0b01, 0b01);
+    const BLUE_GROUP: InteractionGroups = InteractionGroups::new(0b10, 0b10);
+
+    /*
+     * A green floor that will collide with the GREEN group only.
+     */
+    let green_floor = ColliderBuilder::cuboid(1.0, 0.1)
+        .translation(0.0, 1.0)
+        .collision_groups(GREEN_GROUP)
+        .build();
+    let green_collider_handle = colliders.insert(green_floor, floor_handle, &mut bodies);
+
+    testbed.set_collider_initial_color(green_collider_handle, Point3::new(0.0, 1.0, 0.0));
+
+    /*
+     * A blue floor that will collide with the BLUE group only.
+     */
+    let blue_floor = ColliderBuilder::cuboid(1.0, 0.1)
+        .translation(0.0, 2.0)
+        .collision_groups(BLUE_GROUP)
+        .build();
+    let blue_collider_handle = colliders.insert(blue_floor, floor_handle, &mut bodies);
+
+    testbed.set_collider_initial_color(blue_collider_handle, Point3::new(0.0, 0.0, 1.0));
+
+    /*
+     * Create the cubes
+     */
+    let num = 8;
+    let rad = 0.1;
+
+    let shift = rad * 2.0;
+    let centerx = shift * (num / 2) as f32;
+    let centery = 2.5;
+
+    for j in 0usize..4 {
+        for i in 0..num {
+            let x = i as f32 * shift - centerx;
+            let y = j as f32 * shift + centery;
+
+            // Alternate between the green and blue groups.
+            let (group, color) = if i % 2 == 0 {
+                (GREEN_GROUP, Point3::new(0.0, 1.0, 0.0))
+            } else {
+                (BLUE_GROUP, Point3::new(0.0, 0.0, 1.0))
+            };
+
+            let rigid_body = RigidBodyBuilder::new_dynamic().translation(x, y).build();
+            let handle = bodies.insert(rigid_body);
+            let collider = ColliderBuilder::cuboid(rad, rad)
+                .collision_groups(group)
+                .build();
+            colliders.insert(collider, handle, &mut bodies);
+
+            testbed.set_body_color(handle, color);
+        }
+    }
+
+    /*
+     * Set up the testbed.
+     */
+    testbed.set_world(bodies, colliders, joints);
+    testbed.look_at(Point2::new(0.0, 1.0), 100.0);
+}
+
+fn main() {
+    let testbed = Testbed::from_builders(0, vec![("Boxes", init_world)]);
+    testbed.run()
+}