Change traversal to keep exact zero distance hits

lib/src/bvh.rs

@@ -40,7 +40,6 @@ impl Bvh{
 			let len=index-last_index;
 			let count=len.div_ceil(MAX_SLICE_LEN);
 			let slice_len=MAX_SLICE_LEN;
-			println!("push_slices index={index} len={len} count={count} slice_len={slice_len}");
 			bvh_nodes.reserve(count);
 			// 0123456789
 			// split into groups of MAX_SLICE_LEN=4
@@ -54,7 +53,6 @@ impl Bvh{
 					let event=&output_events[slice.end];
 					aabb.grow(vec3::try_from_f32_array([event.event.position.x,event.event.position.y,event.event.position.z]).unwrap());
 				}
-				println!("EventSlice slice={slice:?} {}",if inclusive{"inclusive"}else{"exclusive"});
 				bvh_nodes.push((EventSlice{slice,inclusive},aabb));
 			};
 			// push fixed-size groups
@@ -89,7 +87,6 @@ impl Bvh{
 				(start_point-p).length_squared()
 			}).min()?;
 			let mut prev_event=&output_events[event_slice.slice.start];
-			let start_time=bot.playback_time(crate::time::from_float(prev_event.time).unwrap());
 			let mut f=|event:&'a v0::Timed<v0::OutputEvent>|{
 				let p0=vec3::try_from_f32_array([prev_event.event.position.x,prev_event.event.position.y,prev_event.event.position.z]).unwrap();
 				let p1=vec3::try_from_f32_array([event.event.position.x,event.event.position.y,event.event.position.z]).unwrap();
@@ -114,10 +111,7 @@ impl Bvh{
 			}
 			if event_slice.inclusive{
 				f(&output_events[event_slice.slice.end]);
-			}else{
 			}
-			let end_time=bot.playback_time(crate::time::from_float(prev_event.time).unwrap());
-			println!("intersect_leaf {:?} {} start_time={} end_time={}",event_slice.slice,if event_slice.inclusive{"inclusive"}else{"exclusive"},start_time,end_time);
 			Some(best_distance)
 		};
 		let intersect_aabb=|aabb:&Aabb|{
@@ -125,7 +119,8 @@ impl Bvh{
 			let clamped_point=start_point.min(aabb.max()).max(aabb.min());
 			Some((start_point-clamped_point).length_squared())
 		};
-		let (_,event_slice)=self.bvh.traverse(start_point,Fixed::ZERO,Fixed::MAX,intersect_leaf,intersect_aabb)?;
+		// traverse uses strict `start_time < t`, so use NEG_EPSILON to keep exact-zero-distance hits.
+		let (_,event_slice)=self.bvh.traverse(start_point,Fixed::NEG_EPSILON,Fixed::MAX,intersect_leaf,intersect_aabb)?;
 
 		// find time at the closest point
 		let (best_time,mut best_distance)=output_events[event_slice.slice.start..event_slice.slice.end].iter().map(|event|{