Combine contact events and intersection events into a single event type and flags

4 files changed, 67 insertions, 69 deletions

diff --git a/src/dynamics/ccd/ccd_solver.rs b/src/dynamics/ccd/ccd_solver.rs
index d15b28c..a4b1419 100644
--- a/src/dynamics/ccd/ccd_solver.rs
+++ b/src/dynamics/ccd/ccd_solver.rs
@@ -5,7 +5,7 @@ use crate::dynamics::{
     RigidBodyCcd, RigidBodyHandle, RigidBodyMassProps, RigidBodyPosition, RigidBodyVelocity,
 };
 use crate::geometry::{
-    ColliderParent, ColliderPosition, ColliderShape, ColliderType, IntersectionEvent, NarrowPhase,
+    ColliderParent, ColliderPosition, ColliderShape, ColliderType, CollisionEvent, NarrowPhase,
 };
 use crate::math::Real;
 use crate::parry::utils::SortedPair;
@@ -613,11 +613,11 @@ impl CCDSolver {
             if !intersect_before
                 && !intersect_after
                 && (co_flags1.active_events | co_flags2.active_events)
-                    .contains(ActiveEvents::INTERSECTION_EVENTS)
+                    .contains(ActiveEvents::COLLISION_EVENTS)
             {
                 // Emit one intersection-started and one intersection-stopped event.
-                events.handle_intersection_event(IntersectionEvent::new(toi.c1, toi.c2, true));
-                events.handle_intersection_event(IntersectionEvent::new(toi.c1, toi.c2, false));
+                events.handle_intersection_event(CollisionEvent::Started(toi.c1, toi.c2));
+                events.handle_intersection_event(CollisionEvent::Stopped(toi.c1, toi.c2));
             }
         }
 
diff --git a/src/geometry/mod.rs b/src/geometry/mod.rs
index 0462cbf..83c687b 100644
--- a/src/geometry/mod.rs
+++ b/src/geometry/mod.rs
@@ -52,38 +52,44 @@ pub type TOI = parry::query::TOI;
 pub use parry::shape::SharedShape;
 
 #[derive(Copy, Clone, Hash, Debug)]
-/// Events occurring when two collision objects start or stop being in contact (or penetration).
-pub enum ContactEvent {
-    /// Event occurring when two collision objects start being in contact.
-    ///
-    /// This event is generated whenever the narrow-phase finds a contact between two collision objects that did not have any contact at the last update.
+/// Events occurring when two colliders start or stop being in contact (or intersecting)
+pub enum CollisionEvent {
+    /// Event occurring when two colliders start being in contact (or intersecting)
     Started(ColliderHandle, ColliderHandle),
-    /// Event occurring when two collision objects stop being in contact.
-    ///
-    /// This event is generated whenever the narrow-phase fails to find any contact between two collision objects that did have at least one contact at the last update.
+    /// Event occurring when two colliders stop being in contact (or intersecting)
     Stopped(ColliderHandle, ColliderHandle),
 }
 
-#[derive(Copy, Clone, Debug)]
-/// Events occurring when two collision objects start or stop being in close proximity, contact, or disjoint.
-pub struct IntersectionEvent {
-    /// The first collider to which the proximity event applies.
-    pub collider1: ColliderHandle,
-    /// The second collider to which the proximity event applies.
-    pub collider2: ColliderHandle,
-    /// Are the two colliders intersecting?
-    pub intersecting: bool,
-}
+impl CollisionEvent {
+    pub(crate) fn new(h1: ColliderHandle, h2: ColliderHandle, start: bool) -> Self {
+        if start {
+            Self::Started(h1, h2)
+        } else {
+            Self::Stopped(h1, h2)
+        }
+    }
+
+    /// Is this a `Started` collision event?
+    pub fn started(self) -> bool {
+        matches!(self, CollisionEvent::Started(_, _))
+    }
+
+    /// Is this a `Stopped` collision event?
+    pub fn stopped(self) -> bool {
+        matches!(self, CollisionEvent::Stopped(_, _))
+    }
+
+    /// The handle of the first collider involved in this collision event.
+    pub fn collider1(self) -> ColliderHandle {
+        match self {
+            Self::Started(h, _) | Self::Stopped(h, _) => h,
+        }
+    }
 
-impl IntersectionEvent {
-    /// Instantiates a new proximity event.
-    ///
-    /// Panics if `prev_status` is equal to `new_status`.
-    pub fn new(collider1: ColliderHandle, collider2: ColliderHandle, intersecting: bool) -> Self {
-        Self {
-            collider1,
-            collider2,
-            intersecting,
+    /// The handle of the second collider involved in this collision event.
+    pub fn collider2(self) -> ColliderHandle {
+        match self {
+            Self::Started(_, h) | Self::Stopped(_, h) => h,
         }
     }
 }
diff --git a/src/geometry/narrow_phase.rs b/src/geometry/narrow_phase.rs
index cf78b81..8a57ef4 100644
--- a/src/geometry/narrow_phase.rs
+++ b/src/geometry/narrow_phase.rs
@@ -8,9 +8,9 @@ use crate::dynamics::{
 };
 use crate::geometry::{
     BroadPhasePairEvent, ColliderChanges, ColliderGraphIndex, ColliderHandle, ColliderMaterial,
-    ColliderPair, ColliderParent, ColliderPosition, ColliderShape, ColliderType, ContactData,
-    ContactEvent, ContactManifold, ContactManifoldData, ContactPair, InteractionGraph,
-    IntersectionEvent, SolverContact, SolverFlags,
+    ColliderPair, ColliderParent, ColliderPosition, ColliderShape, ColliderType, CollisionEvent,
+    ContactData, ContactManifold, ContactManifoldData, ContactPair, InteractionGraph,
+    SolverContact, SolverFlags,
 };
 use crate::math::{Real, Vector};
 use crate::pipeline::{
@@ -516,10 +516,10 @@ impl NarrowPhase {
                         let co_flag2: &ColliderFlags = colliders.index(pair.collider2.0);
 
                         if (co_flag1.active_events | co_flag2.active_events)
-                            .contains(ActiveEvents::INTERSECTION_EVENTS)
+                            .contains(ActiveEvents::COLLISION_EVENTS)
                         {
                             let prox_event =
-                                IntersectionEvent::new(pair.collider1, pair.collider2, false);
+                                CollisionEvent::Stopped(pair.collider1, pair.collider2);
                             events.handle_intersection_event(prox_event)
                         }
                     }
@@ -551,10 +551,10 @@ impl NarrowPhase {
                             let co_flag2: &ColliderFlags = colliders.index(pair.collider2.0);
 
                             if (co_flag1.active_events | co_flag2.active_events)
-                                .contains(ActiveEvents::CONTACT_EVENTS)
+                                .contains(ActiveEvents::COLLISION_EVENTS)
                             {
                                 events.handle_contact_event(
-                                    ContactEvent::Stopped(pair.collider1, pair.collider2),
+                                    CollisionEvent::Stopped(pair.collider1, pair.collider2),
                                     &ctct,
                                 )
                             }
@@ -795,10 +795,10 @@ impl NarrowPhase {
             let co_flags2: &ColliderFlags = colliders.index(handle2.0);
             let active_events = co_flags1.active_events | co_flags2.active_events;
 
-            if active_events.contains(ActiveEvents::INTERSECTION_EVENTS)
+            if active_events.contains(ActiveEvents::COLLISION_EVENTS)
                 && had_intersection != edge.weight
             {
-                events.handle_intersection_event(IntersectionEvent::new(
+                events.handle_intersection_event(CollisionEvent::new(
                     handle1,
                     handle2,
                     edge.weight,
@@ -1027,15 +1027,15 @@ impl NarrowPhase {
             let active_events = co_flags1.active_events | co_flags2.active_events;
 
             if pair.has_any_active_contact != had_any_active_contact {
-                if active_events.contains(ActiveEvents::CONTACT_EVENTS) {
+                if active_events.contains(ActiveEvents::COLLISION_EVENTS) {
                     if pair.has_any_active_contact {
                         events.handle_contact_event(
-                            ContactEvent::Started(pair.collider1, pair.collider2),
+                            CollisionEvent::Started(pair.collider1, pair.collider2),
                             pair,
                         );
                     } else {
                         events.handle_contact_event(
-                            ContactEvent::Stopped(pair.collider1, pair.collider2),
+                            CollisionEvent::Stopped(pair.collider1, pair.collider2),
                             pair,
                         );
                     }
diff --git a/src/pipeline/event_handler.rs b/src/pipeline/event_handler.rs
index c54acc2..5fa90c6 100644
--- a/src/pipeline/event_handler.rs
+++ b/src/pipeline/event_handler.rs
@@ -1,14 +1,13 @@
-use crate::geometry::{ContactEvent, ContactPair, IntersectionEvent};
+use crate::geometry::{CollisionEvent, ContactPair};
 use crossbeam::channel::Sender;
 
 bitflags::bitflags! {
     #[cfg_attr(feature = "serde-serialize", derive(Serialize, Deserialize))]
     /// Flags affecting the events generated for this collider.
     pub struct ActiveEvents: u32 {
-        /// If set, Rapier will call `EventHandler::handle_intersection_event` whenever relevant for this collider.
-        const INTERSECTION_EVENTS = 0b0001;
-        /// If set, Rapier will call `PhysicsHooks::handle_contact_event` whenever relevant for this collider.
-        const CONTACT_EVENTS = 0b0010;
+        /// If set, Rapier will call `EventHandler::handle_intersection_event` and
+        /// `EventHandler::handle_contact_event` whenever relevant for this collider.
+        const COLLISION_EVENTS = 0b0001;
     }
 }
 
@@ -22,47 +21,40 @@ impl Default for ActiveEvents {
 ///
 /// Implementors of this trait will typically collect these events for future processing.
 pub trait EventHandler: Send + Sync {
-    /// Handle an intersection event.
+    /// Handle a collision event.
     ///
     /// A intersection event is emitted when the state of intersection between two colliders changes.
-    fn handle_intersection_event(&self, event: IntersectionEvent);
+    fn handle_intersection_event(&self, event: CollisionEvent);
     /// Handle a contact event.
     ///
     /// A contact event is emitted when two collider start or stop touching, independently from the
     /// number of contact points involved.
-    fn handle_contact_event(&self, event: ContactEvent, contact_pair: &ContactPair);
+    fn handle_contact_event(&self, event: CollisionEvent, contact_pair: &ContactPair);
 }
 
 impl EventHandler for () {
-    fn handle_intersection_event(&self, _event: IntersectionEvent) {}
-    fn handle_contact_event(&self, _event: ContactEvent, _contact_pair: &ContactPair) {}
+    fn handle_intersection_event(&self, _event: CollisionEvent) {}
+    fn handle_contact_event(&self, _event: CollisionEvent, _contact_pair: &ContactPair) {}
 }
 
-/// A physics event handler that collects events into a crossbeam channel.
+/// A collision event handler that collects events into a crossbeam channel.
 pub struct ChannelEventCollector {
-    intersection_event_sender: Sender<IntersectionEvent>,
-    contact_event_sender: Sender<ContactEvent>,
+    event_sender: Sender<CollisionEvent>,
 }
 
 impl ChannelEventCollector {
-    /// Initialize a new physics event handler from crossbeam channel senders.
-    pub fn new(
-        intersection_event_sender: Sender<IntersectionEvent>,
-        contact_event_sender: Sender<ContactEvent>,
-    ) -> Self {
-        Self {
-            intersection_event_sender,
-            contact_event_sender,
-        }
+    /// Initialize a new collision event handler from crossbeam channel senders.
+    pub fn new(event_sender: Sender<CollisionEvent>) -> Self {
+        Self { event_sender }
     }
 }
 
 impl EventHandler for ChannelEventCollector {
-    fn handle_intersection_event(&self, event: IntersectionEvent) {
-        let _ = self.intersection_event_sender.send(event);
+    fn handle_intersection_event(&self, event: CollisionEvent) {
+        let _ = self.event_sender.send(event);
     }
 
-    fn handle_contact_event(&self, event: ContactEvent, _: &ContactPair) {
-        let _ = self.contact_event_sender.send(event);
+    fn handle_contact_event(&self, event: CollisionEvent, _: &ContactPair) {
+        let _ = self.event_sender.send(event);
     }
 }