feat: migrate to glam whenever relevant + migrate testbed to kiss3d instead of bevy + release v0.32.0 (#909)

* feat: migrate to glam whenever relevant + migrate testbed to kiss3d instead of bevy

* chore: update changelog

* Fix warnings and tests

* Release v0.32.0

examples2d/stress_tests/heightfield2.rs

@@ -0,0 +1,68 @@
+use rapier_testbed2d::Testbed;
+use rapier2d::prelude::*;
+
+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();
+
+    /*
+     * Ground
+     */
+    let ground_size = Vec2::new(50.0, 1.0);
+    let nsubdivs = 2000;
+
+    let heights = (0..nsubdivs + 1)
+        .map(|i| {
+            if i == 0 || i == nsubdivs {
+                80.0
+            } else {
+                (i as f32 * ground_size.x / (nsubdivs as f32)).cos() * 2.0
+            }
+        })
+        .collect();
+
+    let rigid_body = RigidBodyBuilder::fixed();
+    let handle = bodies.insert(rigid_body);
+    let collider = ColliderBuilder::heightfield(heights, ground_size);
+    colliders.insert_with_parent(collider, handle, &mut bodies);
+
+    /*
+     * Create the cubes
+     */
+    let num = 26;
+    let rad = 0.5;
+
+    let shift = rad * 2.0;
+    let centerx = shift * (num / 2) as f32;
+    let centery = shift / 2.0;
+
+    for i in 0..num {
+        for j in 0usize..num * 5 {
+            let x = i as f32 * shift - centerx;
+            let y = j as f32 * shift + centery + 3.0;
+
+            // Build the rigid body.
+            let rigid_body = RigidBodyBuilder::dynamic().translation(Vec2::new(x, y));
+            let handle = bodies.insert(rigid_body);
+
+            if j % 2 == 0 {
+                let collider = ColliderBuilder::cuboid(rad, rad);
+                colliders.insert_with_parent(collider, handle, &mut bodies);
+            } else {
+                let collider = ColliderBuilder::ball(rad);
+                colliders.insert_with_parent(collider, handle, &mut bodies);
+            }
+        }
+    }
+
+    /*
+     * Set up the testbed.
+     */
+    testbed.set_world(bodies, colliders, impulse_joints, multibody_joints);
+    testbed.look_at(Vec2::new(0.0, 50.0), 10.0);
+}