Projection friction impulses on an implicit cone instead of a pyramidal approximation.

3 files changed, 53 insertions, 1 deletions

diff --git a/examples3d/all_examples3.rs b/examples3d/all_examples3.rs
index 8a71665..724aa45 100644
--- a/examples3d/all_examples3.rs
+++ b/examples3d/all_examples3.rs
@@ -19,6 +19,7 @@ mod debug_add_remove_collider3;
 mod debug_boxes3;
 mod debug_cylinder3;
 mod debug_dynamic_collider_add3;
+mod debug_friction3;
 mod debug_infinite_fall3;
 mod debug_rollback3;
 mod debug_triangle3;
@@ -99,6 +100,7 @@ pub fn main() {
             "(Debug) dyn. coll. add",
             debug_dynamic_collider_add3::init_world,
         ),
+        ("(Debug) friction", debug_friction3::init_world),
         ("(Debug) triangle", debug_triangle3::init_world),
         ("(Debug) trimesh", debug_trimesh3::init_world),
         ("(Debug) cylinder", debug_cylinder3::init_world),
diff --git a/examples3d/debug_friction3.rs b/examples3d/debug_friction3.rs
new file mode 100644
index 0000000..5cf40b3
--- /dev/null
+++ b/examples3d/debug_friction3.rs
@@ -0,0 +1,50 @@
+use na::{Point3, Vector3};
+use rapier3d::dynamics::{JointSet, RigidBodyBuilder, RigidBodySet};
+use rapier3d::geometry::{ColliderBuilder, ColliderSet};
+use rapier_testbed3d::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 = 100.0;
+    let ground_height = 0.1;
+
+    let rigid_body = RigidBodyBuilder::new_static().build();
+    let handle = bodies.insert(rigid_body);
+    let collider = ColliderBuilder::cuboid(ground_size, ground_height, ground_size)
+        .friction(1.5)
+        .build();
+    colliders.insert(collider, handle, &mut bodies);
+
+    // Build a dynamic box rigid body.
+    let rigid_body = RigidBodyBuilder::new_dynamic()
+        .translation(0.0, 1.1, 0.0)
+        .rotation(Vector3::y() * 0.3)
+        .build();
+    let handle = bodies.insert(rigid_body);
+    let collider = ColliderBuilder::cuboid(2.0, 1.0, 3.0).friction(1.5).build();
+    colliders.insert(collider, handle, &mut bodies);
+
+    let rigid_body = &mut bodies[handle];
+    let force = rigid_body.position() * Vector3::z() * 50.0;
+    rigid_body.set_linvel(force, true);
+
+    /*
+     * Set up the testbed.
+     */
+    testbed.set_world(bodies, colliders, joints);
+    testbed.look_at(Point3::new(10.0, 10.0, 10.0), Point3::origin());
+}
+
+fn main() {
+    let testbed = Testbed::from_builders(0, vec![("Boxes", init_world)]);
+    testbed.run()
+}
diff --git a/examples3d/one_way_platforms3.rs b/examples3d/one_way_platforms3.rs
index 173d03d..d117a5b 100644
--- a/examples3d/one_way_platforms3.rs
+++ b/examples3d/one_way_platforms3.rs
@@ -40,7 +40,7 @@ impl PhysicsHooks for OneWayPlatformHook {
             allowed_local_n1 = -Vector3::y();
         } else if context.collider_handle2 == self.platform2 {
             // Flip the allowed direction.
-            allowed_local_n1 = -Vector3::y();
+            allowed_local_n1 = Vector3::y();
         }
 
         // Call the helper function that simulates one-way platforms.