1 files changed, 111 insertions, 0 deletions
diff --git a/src/pipeline/collision_pipeline.rs b/src/pipeline/collision_pipeline.rs
new file mode 100644
index 0000000..0184295
--- /dev/null
+++ b/src/pipeline/collision_pipeline.rs
@@ -0,0 +1,111 @@
+//! Physics pipeline structures.
+
+use crate::dynamics::{JointSet, RigidBody, RigidBodyHandle, RigidBodySet};
+use crate::geometry::{BroadPhase, BroadPhasePairEvent, ColliderPair, ColliderSet, NarrowPhase};
+use crate::pipeline::EventHandler;
+
+/// The collision pipeline, responsible for performing collision detection between colliders.
+///
+/// This structure only contains temporary data buffers. It can be dropped and replaced by a fresh
+/// copy at any time. For performance reasons it is recommended to reuse the same physics pipeline
+/// instance to benefit from the cached data.
+// NOTE: this contains only workspace data, so there is no point in making this serializable.
+pub struct CollisionPipeline {
+    broadphase_collider_pairs: Vec<ColliderPair>,
+    broad_phase_events: Vec<BroadPhasePairEvent>,
+    empty_joints: JointSet,
+}
+
+#[allow(dead_code)]
+fn check_pipeline_send_sync() {
+    fn do_test<T: Sync>() {}
+    do_test::<CollisionPipeline>();
+}
+
+impl CollisionPipeline {
+    /// Initializes a new physics pipeline.
+    pub fn new() -> CollisionPipeline {
+        CollisionPipeline {
+            broadphase_collider_pairs: Vec::new(),
+            broad_phase_events: Vec::new(),
+            empty_joints: JointSet::new(),
+        }
+    }
+
+    /// Executes one step of the collision detection.
+    pub fn step(
+        &mut self,
+        prediction_distance: f32,
+        broad_phase: &mut BroadPhase,
+        narrow_phase: &mut NarrowPhase,
+        bodies: &mut RigidBodySet,
+        colliders: &mut ColliderSet,
+        events: &dyn EventHandler,
+    ) {
+        bodies.maintain_active_set();
+        self.broadphase_collider_pairs.clear();
+
+        broad_phase.update_aabbs(prediction_distance, bodies, colliders);
+
+        self.broad_phase_events.clear();
+        broad_phase.find_pairs(&mut self.broad_phase_events);
+
+        narrow_phase.register_pairs(colliders, &self.broad_phase_events, events);
+
+        narrow_phase.compute_contacts(prediction_distance, bodies, colliders, events);
+        narrow_phase.compute_proximities(prediction_distance, bodies, colliders, events);
+
+        bodies.update_active_set_with_contacts(
+            colliders,
+            narrow_phase.contact_graph(),
+            self.empty_joints.joint_graph(),
+            0,
+        );
+
+        // // Update kinematic bodies velocities.
+        // bodies.foreach_active_kinematic_body_mut_internal(|_, body| {
+        //     body.compute_velocity_from_predicted_position(integration_parameters.inv_dt());
+        // });
+
+        // Update colliders positions and kinematic bodies positions.
+        bodies.foreach_active_body_mut_internal(|_, rb| {
+            if rb.is_kinematic() {
+                rb.position = rb.predicted_position;
+            } else {
+                rb.update_predicted_position(0.0);
+            }
+
+            for handle in &rb.colliders {
+                let collider = &mut colliders[*handle];
+                collider.position = rb.position * collider.delta;
+                collider.predicted_position = rb.predicted_position * collider.delta;
+            }
+        });
+
+        bodies.modified_inactive_set.clear();
+    }
+
+    /// Remove a rigid-body and all its associated data.
+    pub fn remove_rigid_body(
+        &mut self,
+        handle: RigidBodyHandle,
+        broad_phase: &mut BroadPhase,
+        narrow_phase: &mut NarrowPhase,
+        bodies: &mut RigidBodySet,
+        colliders: &mut ColliderSet,
+    ) -> Option<RigidBody> {
+        // Remove the body.
+        let body = bodies.remove_internal(handle)?;
+
+        // Remove this rigid-body from the broad-phase and narrow-phase.
+        broad_phase.remove_colliders(&body.colliders, colliders);
+        narrow_phase.remove_colliders(&body.colliders, colliders, bodies);
+
+        // Remove all colliders attached to this body.
+        for collider in &body.colliders {
+            colliders.remove_internal(*collider);
+        }
+
+        Some(body)
+    }
+}