Add restitution.

examples2d/restitution2.rs

@@ -0,0 +1,56 @@
+use na::Point2;
+use rapier2d::dynamics::{JointSet, RigidBodyBuilder, RigidBodySet};
+use rapier2d::geometry::{ColliderBuilder, ColliderSet};
+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 = 20.;
+    let ground_height = 1.0;
+
+    let rigid_body = RigidBodyBuilder::new_static()
+        .translation(0.0, -ground_height)
+        .build();
+    let handle = bodies.insert(rigid_body);
+    let collider = ColliderBuilder::cuboid(ground_size, ground_height)
+        .restitution(1.0)
+        .build();
+    colliders.insert(collider, handle, &mut bodies);
+
+    let num = 10;
+    let rad = 0.5;
+
+    for j in 0..2 {
+        for i in 0..=num {
+            let x = (i as f32) - num as f32 / 2.0;
+            let rigid_body = RigidBodyBuilder::new_dynamic()
+                .translation(x * 2.0, 10.0 * (j as f32 + 1.0))
+                .build();
+            let handle = bodies.insert(rigid_body);
+            let collider = ColliderBuilder::ball(rad)
+                .restitution((i as f32) / (num as f32))
+                .build();
+            colliders.insert(collider, handle, &mut bodies);
+        }
+    }
+
+    /*
+     * Set up the testbed.
+     */
+    testbed.set_world(bodies, colliders, joints);
+    testbed.look_at(Point2::new(0.0, 1.0), 25.0);
+}
+
+fn main() {
+    let testbed = Testbed::from_builders(0, vec![("Boxes", init_world)]);
+    testbed.run()
+}