negative everything

engine/physics/src/minimum_difference.rs

@@ -1,23 +1,20 @@
 use strafesnet_common::integer::vec3;
 use strafesnet_common::integer::vec3::Vector3;
-use strafesnet_common::integer::{Fixed,Planar64,Planar64Vec3};
+use strafesnet_common::integer::{Fixed,Planar64Vec3};
 
-use crate::model::{DirectedEdge,FEV,MeshQuery};
-// TODO: remove mesh invert
-use crate::model::{MinkowskiMesh,MinkowskiVert};
+use crate::model::{MeshQuery,MinkowskiMesh,MinkowskiVert};
 
 // This algorithm is based on Lua code
 // written by Trey Reynolds in 2021
 
-type Simplex<const N:usize,Vert>=[Vert;N];
-#[derive(Clone,Copy)]
-enum Simplex1_3<Vert>{
-	Simplex1(Simplex<1,Vert>),
-	Simplex2(Simplex<2,Vert>),
-	Simplex3(Simplex<3,Vert>),
+type Simplex<const N:usize>=[MinkowskiVert;N];
+enum Simplex1_3{
+	Simplex1(Simplex<1>),
+	Simplex2(Simplex<2>),
+	Simplex3(Simplex<3>),
 }
-impl<Vert> Simplex1_3<Vert>{
-	fn push_front(self,v:Vert)->Simplex2_4<Vert>{
+impl Simplex1_3{
+	fn push_front(self,v:MinkowskiVert)->Simplex2_4{
 		match self{
 			Simplex1_3::Simplex1([v0])=>Simplex2_4::Simplex2([v,v0]),
 			Simplex1_3::Simplex2([v0,v1])=>Simplex2_4::Simplex3([v,v0,v1]),
@@ -25,11 +22,10 @@ impl<Vert> Simplex1_3<Vert>{
 		}
 	}
 }
-#[derive(Clone,Copy)]
-enum Simplex2_4<Vert>{
-	Simplex2(Simplex<2,Vert>),
-	Simplex3(Simplex<3,Vert>),
-	Simplex4(Simplex<4,Vert>),
+enum Simplex2_4{
+	Simplex2(Simplex<2>),
+	Simplex3(Simplex<3>),
+	Simplex4(Simplex<4>),
 }
 
 /*
@@ -45,23 +41,23 @@ local function absDet(r, u, v, w)
 	end
 end
 */
-impl<Vert> Simplex2_4<Vert>{
-	fn det_is_zero<M:MeshQuery<Vert=Vert>>(self,mesh:&M)->bool{
+impl Simplex2_4{
+	fn det_is_zero(&self,mesh:&MinkowskiMesh)->bool{
 		match self{
-			Self::Simplex4([p0,p1,p2,p3])=>{
+			&Self::Simplex4([p0,p1,p2,p3])=>{
 				let p0=mesh.vert(p0);
 				let p1=mesh.vert(p1);
 				let p2=mesh.vert(p2);
 				let p3=mesh.vert(p3);
 				(p1-p0).cross(p2-p0).dot(p3-p0)==Fixed::ZERO
 			},
-			Self::Simplex3([p0,p1,p2])=>{
+			&Self::Simplex3([p0,p1,p2])=>{
 				let p0=mesh.vert(p0);
 				let p1=mesh.vert(p1);
 				let p2=mesh.vert(p2);
 				(p1-p0).cross(p2-p0)==vec3::zero()
 			},
-			Self::Simplex2([p0,p1])=>{
+			&Self::Simplex2([p0,p1])=>{
 				let p0=mesh.vert(p0);
 				let p1=mesh.vert(p1);
 				p1-p0==vec3::zero()
@@ -100,14 +96,14 @@ const fn choose_any_direction()->Planar64Vec3{
 	vec3::X
 }
 
-fn reduce1<M:MeshQuery>(
-	[v0]:Simplex<1,M::Vert>,
-	mesh:&M,
+fn reduce1(
+	[v0]:Simplex<1>,
+	mesh:&MinkowskiMesh,
 	point:Planar64Vec3,
-)->Reduced<M::Vert>{
+)->Reduced{
 	// --debug.profilebegin("reduceSimplex0")
 	// local a = a1 - a0
-	let p0=mesh.vert(v0);
+	let p0=-mesh.vert(v0);
 
 	// local p = -a
 	let p=-(p0+point);
@@ -129,16 +125,16 @@ fn reduce1<M:MeshQuery>(
 }
 
 // local function reduceSimplex1(a0, a1, b0, b1)
-fn reduce2<M:MeshQuery>(
-	[v0,v1]:Simplex<2,M::Vert>,
-	mesh:&M,
+fn reduce2(
+	[v0,v1]:Simplex<2>,
+	mesh:&MinkowskiMesh,
 	point:Planar64Vec3,
-)->Reduced<M::Vert>{
+)->Reduced{
 	// --debug.profilebegin("reduceSimplex1")
 	// local a = a1 - a0
 	// local b = b1 - b0
-	let p0=mesh.vert(v0);
-	let p1=mesh.vert(v1);
+	let p0=-mesh.vert(v0);
+	let p1=-mesh.vert(v1);
 
 	// local p = -a
 	// local u = b - a
@@ -186,18 +182,18 @@ fn reduce2<M:MeshQuery>(
 }
 
 // local function reduceSimplex2(a0, a1, b0, b1, c0, c1)
-fn reduce3<M:MeshQuery>(
-	[v0,mut v1,v2]:Simplex<3,M::Vert>,
-	mesh:&M,
+fn reduce3(
+	[v0,mut v1,v2]:Simplex<3>,
+	mesh:&MinkowskiMesh,
 	point:Planar64Vec3,
-)->Reduced<M::Vert>{
+)->Reduced{
 	// --debug.profilebegin("reduceSimplex2")
 	// local a = a1 - a0
 	// local b = b1 - b0
 	// local c = c1 - c0
-	let p0=mesh.vert(v0);
-	let p1=mesh.vert(v1);
-	let p2=mesh.vert(v2);
+	let p0=-mesh.vert(v0);
+	let p1=-mesh.vert(v1);
+	let p2=-mesh.vert(v2);
 
 	// local p = -a
 	// local u = b - a
@@ -295,20 +291,20 @@ fn reduce3<M:MeshQuery>(
 }
 
 // local function reduceSimplex3(a0, a1, b0, b1, c0, c1, d0, d1)
-fn reduce4<M:MeshQuery>(
-	[v0,mut v1,mut v2,v3]:Simplex<4,M::Vert>,
-	mesh:&M,
+fn reduce4(
+	[v0,mut v1,mut v2,v3]:Simplex<4>,
+	mesh:&MinkowskiMesh,
 	point:Planar64Vec3,
-)->Reduce<M::Vert>{
+)->Reduce{
 	// --debug.profilebegin("reduceSimplex3")
 	// local a = a1 - a0
 	// local b = b1 - b0
 	// local c = c1 - c0
 	// local d = d1 - d0
-	let p0=mesh.vert(v0);
-	let p1=mesh.vert(v1);
-	let p2=mesh.vert(v2);
-	let p3=mesh.vert(v3);
+	let p0=-mesh.vert(v0);
+	let p1=-mesh.vert(v1);
+	let p2=-mesh.vert(v2);
+	let p3=-mesh.vert(v3);
 
 	// local p = -a
 	// local u = b - a
@@ -484,18 +480,18 @@ fn reduce4<M:MeshQuery>(
 	})
 }
 
-struct Reduced<Vert>{
+struct Reduced{
 	dir:Planar64Vec3,
-	simplex:Simplex1_3<Vert>,
+	simplex:Simplex1_3,
 }
 
-enum Reduce<Vert>{
-	Escape(Simplex<4,Vert>),
-	Reduced(Reduced<Vert>),
+enum Reduce{
+	Escape(Simplex<4>),
+	Reduced(Reduced),
 }
 
-impl<Vert> Simplex2_4<Vert>{
-	fn reduce<M:MeshQuery<Vert=Vert>>(self,mesh:&M,point:Planar64Vec3)->Reduce<Vert>{
+impl Simplex2_4{
+	fn reduce(self,mesh:&MinkowskiMesh,point:Planar64Vec3)->Reduce{
 		match self{
 			Self::Simplex2(simplex)=>Reduce::Reduced(reduce2(simplex,mesh,point)),
 			Self::Simplex3(simplex)=>Reduce::Reduced(reduce3(simplex,mesh,point)),
@@ -504,13 +500,57 @@ impl<Vert> Simplex2_4<Vert>{
 	}
 }
 
-pub fn contains_point(mesh:&MinkowskiMesh<'_>,point:Planar64Vec3)->bool{
+// local function expand(
+// 	queryP, queryQ,
+// 	vertA0, vertA1,
+// 	vertB0, vertB1,
+// 	vertC0, vertC1,
+// 	vertD0, vertD1,
+// 	accuracy
+// )
+fn refine_to_exact(mesh:&MinkowskiMesh,simplex:Simplex<4>)->Simplex2_4{
+	unimplemented!()
+}
+
+/// Intermediate data structure containing a partially complete calculation.
+/// Sometimes you only care about the topology, and not about the
+/// exact point of intersection details.
+pub struct Topology{
+	simplex:Simplex2_4,
+}
+impl Topology{
+	/// Returns None if the point is intersecting the mesh.
+	pub fn closest_point_details(self,mesh:&MinkowskiMesh)->Option<Details>{
+		// NOTE: if hits is true, this if statement necessarily evaluates to true.
+		// i.e. hits implies this statement
+		// if -dist <= exitRadius + radiusP + radiusQ then
+		// 	local posP, posQ = decompose(-point, a0, a1, b0, b1, c0, c1)
+		// 	return hits, -dist - radiusP - radiusQ,
+		// 		posP - radiusP*norm, -norm,
+		// 		posQ + radiusQ*norm, norm
+		// end
+		// return false
+		unimplemented!()
+	}
+}
+pub struct Details{
+	// distance:Planar64,
+	// p_pos:Planar64Vec3,
+	// p_norm:Planar64Vec3,
+	// q_pos:Planar64Vec3,
+	// q_norm:Planar64Vec3,
+}
+
+pub fn contains_point(mesh:&MinkowskiMesh,point:Planar64Vec3)->bool{
 	const ENABLE_FAST_FAIL:bool=true;
-	// TODO: remove mesh negation
-	minimum_difference::<ENABLE_FAST_FAIL,_,_>(&-mesh,point,
+	minimum_difference::<ENABLE_FAST_FAIL,_>(mesh,point,
 		// on_exact
-		|is_intersecting,_simplex|{
-			is_intersecting
+		|last_pos,direction|{
+			// local norm = direction.unit
+			// local dist = a:Dot(norm)
+			// local hits = -dist < radiusP + radiusQ
+			// return hits
+			(last_pos+point).dot(direction).is_positive()
 		},
 		// on_escape
 		|_simplex|{
@@ -521,248 +561,16 @@ pub fn contains_point(mesh:&MinkowskiMesh<'_>,point:Planar64Vec3)->bool{
 		||false
 	)
 }
-
-//infinity fev algorithm state transition
-#[derive(Debug)]
-enum Transition<Vert>{
-	Done,//found closest vert, no edges are better
-	Vert(Vert),//transition to vert
-}
-enum EV<M:MeshQuery>{
-	Vert(M::Vert),
-	Edge(<M::Edge as DirectedEdge>::UndirectedEdge),
-}
-impl<M:MeshQuery> From<EV<M>> for FEV<M>{
-	fn from(value:EV<M>)->Self{
-		match value{
-			EV::Vert(minkowski_vert)=>FEV::Vert(minkowski_vert),
-			EV::Edge(minkowski_edge)=>FEV::Edge(minkowski_edge),
-		}
-	}
-}
-
-trait Contains{
-	fn contains(&self,point:Planar64Vec3)->bool;
-}
-
-// convenience type to check if a point is within some threshold of a plane.
-struct ThickPlane{
-	point:Planar64Vec3,
-	normal:Vector3<Fixed<2,64>>,
-	epsilon:Fixed<3,96>,
-}
-impl ThickPlane{
-	fn new<M:MeshQuery>(mesh:&M,[v0,v1,v2]:Simplex<3,M::Vert>)->Self{
-		let p0=mesh.vert(v0);
-		let p1=mesh.vert(v1);
-		let p2=mesh.vert(v2);
-		let point=p0;
-		let normal=(p1-p0).cross(p2-p0);
-		// Allow ~ 2*sqrt(3) units of thickness on the plane
-		// This is to account for the variance of two voxels across the longest diagonal
-		let epsilon=(normal.length()*(Planar64::EPSILON*3)).wrap_3();
-		Self{point,normal,epsilon}
-	}
-}
-impl Contains for ThickPlane{
-	fn contains(&self,point:Planar64Vec3)->bool{
-		(point-self.point).dot(self.normal).abs()<=self.epsilon
-	}
-}
-
-struct ThickLine{
-	point:Planar64Vec3,
-	dir:Planar64Vec3,
-	epsilon:Fixed<4,128>,
-}
-impl ThickLine{
-	fn new<M:MeshQuery>(mesh:&M,[v0,v1]:Simplex<2,M::Vert>)->Self{
-		let p0=mesh.vert(v0);
-		let p1=mesh.vert(v1);
-		let point=p0;
-		let dir=p1-p0;
-		// Allow ~ 2*sqrt(3) units of thickness on the plane
-		// This is to account for the variance of two voxels across the longest diagonal
-		let epsilon=(dir.length_squared()*(Planar64::EPSILON*3)).widen_4();
-		Self{point,dir,epsilon}
-	}
-}
-impl Contains for ThickLine{
-	fn contains(&self,point:Planar64Vec3)->bool{
-		(point-self.point).cross(self.dir).length_squared()<=self.epsilon
-	}
-}
-
-struct EVFinder<'a,M,C>{
-	mesh:&'a M,
-	constraint:C,
-	best_distance_squared:Fixed<2,64>,
-}
-
-impl<M:MeshQuery,C:Contains> EVFinder<'_,M,C>{
-	fn next_transition_vert(&mut self,vert_id:M::Vert,point:Planar64Vec3)->Transition<M::Vert>{
-		let mut best_transition=Transition::Done;
-		for &directed_edge_id in self.mesh.vert_edges(vert_id).as_ref(){
-			//test if this edge's opposite vertex closer
-			let edge_verts=self.mesh.edge_verts(directed_edge_id.as_undirected());
-			//select opposite vertex
-			let test_vert_id=edge_verts.as_ref()[directed_edge_id.parity() as usize];
-			let test_pos=self.mesh.vert(test_vert_id);
-			let diff=point-test_pos;
-			let distance_squared=diff.dot(diff);
-			// ensure test_vert_id is coplanar to simplex
-			if distance_squared<self.best_distance_squared&&self.constraint.contains(test_pos){
-				best_transition=Transition::Vert(test_vert_id);
-				self.best_distance_squared=distance_squared;
-			}
-		}
-		best_transition
-	}
-	fn final_ev(&mut self,vert_id:M::Vert,point:Planar64Vec3)->EV<M>{
-		let mut best_transition=EV::Vert(vert_id);
-		let vert_pos=self.mesh.vert(vert_id);
-		let diff=point-vert_pos;
-		for &directed_edge_id in self.mesh.vert_edges(vert_id).as_ref(){
-			//test if this edge is closer
-			let edge_verts=self.mesh.edge_verts(directed_edge_id.as_undirected());
-			let test_vert_id=edge_verts.as_ref()[directed_edge_id.parity() as usize];
-			let test_pos=self.mesh.vert(test_vert_id);
-			let edge_n=test_pos-vert_pos;
-			let d=edge_n.dot(diff);
-			//test the edge
-			let edge_nn=edge_n.dot(edge_n);
-			// ensure edge contains closest point and directed_edge_id is coplanar to simplex
-			if !d.is_negative()&&d<=edge_nn&&self.constraint.contains(test_pos){
-				let distance_squared={
-					let c=diff.cross(edge_n);
-					//wrap for speed
-					(c.dot(c)/edge_nn).divide().wrap_2()
-				};
-				if distance_squared<=self.best_distance_squared{
-					best_transition=EV::Edge(directed_edge_id.as_undirected());
-					self.best_distance_squared=distance_squared;
-				}
-			}
-		}
-		best_transition
-	}
-	fn crawl_boundaries(&mut self,mut vert_id:M::Vert,point:Planar64Vec3)->EV<M>{
-		loop{
-			match self.next_transition_vert(vert_id,point){
-				Transition::Done=>return self.final_ev(vert_id,point),
-				Transition::Vert(new_vert_id)=>vert_id=new_vert_id,
-			}
-		}
-	}
-}
-/// This function drops a vertex down to an edge or a face if the path from infinity did not cross any vertex-edge boundaries but the point is supposed to have already crossed a boundary down from a vertex
-fn crawl_to_closest_ev<M:MeshQuery>(mesh:&M,simplex:Simplex<2,M::Vert>,point:Planar64Vec3)->EV<M>{
-	// naively start at the closest vertex
-	// the closest vertex is not necessarily the one with the fewest boundary hops
-	// but it doesn't matter, we will get there regardless.
-	let (vert_id,best_distance_squared)=simplex.into_iter().map(|vert_id|{
-		let diff=point-mesh.vert(vert_id);
-		(vert_id,diff.dot(diff))
-	}).min_by_key(|&(_,d)|d).unwrap();
-
-	let constraint=ThickLine::new(mesh,simplex);
-	let mut finder=EVFinder{constraint,mesh,best_distance_squared};
-	//start on any vertex
-	//cross uncrossable vertex-edge boundaries until you find the closest vertex or edge
-	//cross edge-face boundary if it's uncrossable
-	finder.crawl_boundaries(vert_id,point)
-}
-
-/// This function drops a vertex down to an edge or a face if the path from infinity did not cross any vertex-edge boundaries but the point is supposed to have already crossed a boundary down from a vertex
-fn crawl_to_closest_fev<'a>(mesh:&MinkowskiMesh<'a>,simplex:Simplex<3,MinkowskiVert>,point:Planar64Vec3)->FEV::<MinkowskiMesh<'a>>{
-	// naively start at the closest vertex
-	// the closest vertex is not necessarily the one with the fewest boundary hops
-	// but it doesn't matter, we will get there regardless.
-	let (vert_id,best_distance_squared)=simplex.into_iter().map(|vert_id|{
-		let diff=point-mesh.vert(vert_id);
-		(vert_id,diff.dot(diff))
-	}).min_by_key(|&(_,d)|d).unwrap();
-
-	let constraint=ThickPlane::new(mesh,simplex);
-	let mut finder=EVFinder{constraint,mesh,best_distance_squared};
-	//start on any vertex
-	//cross uncrossable vertex-edge boundaries until you find the closest vertex or edge
-	//cross edge-face boundary if it's uncrossable
-	match finder.crawl_boundaries(vert_id,point){
-		//if a vert is returned, it is the closest point to the infinity point
-		EV::Vert(vert_id)=>FEV::Vert(vert_id),
-		EV::Edge(edge_id)=>{
-			//cross to face if we are on the wrong side
-			let edge_n=mesh.edge_n(edge_id);
-			// point is multiplied by two because vert_sum sums two vertices.
-			let delta_pos=point*2-{
-				let &[v0,v1]=mesh.edge_verts(edge_id).as_ref();
-				mesh.vert(v0)+mesh.vert(v1)
-			};
-			for (i,&face_id) in mesh.edge_faces(edge_id).as_ref().iter().enumerate(){
-				//test if this face is closer
-				let (face_n,d)=mesh.face_nd(face_id);
-				//if test point is behind face, the face is invalid
-				// TODO: find out why I thought of this backwards
-				if !(face_n.dot(point)-d).is_positive(){
-					continue;
-				}
-				//edge-face boundary nd, n facing out of the face towards the edge
-				let boundary_n=face_n.cross(edge_n)*(i as i64*2-1);
-				let boundary_d=boundary_n.dot(delta_pos);
-				//is test point behind edge, i.e. contained in the face
-				if !boundary_d.is_positive(){
-					//both faces cannot pass this condition, return early if one does.
-					return FEV::Face(face_id);
-				}
-			}
-			FEV::Edge(edge_id)
-		},
-	}
-}
-
-pub fn closest_fev_not_inside<'a>(mesh:&MinkowskiMesh<'a>,point:Planar64Vec3)->Option<FEV<MinkowskiMesh<'a>>>{
+pub fn closest_fev(mesh:&MinkowskiMesh,point:Planar64Vec3)->Topology{
 	const ENABLE_FAST_FAIL:bool=false;
-	// TODO: remove mesh negation
-	minimum_difference::<ENABLE_FAST_FAIL,_,_>(&-mesh,point,
+	minimum_difference::<ENABLE_FAST_FAIL,_>(mesh,point,
 		// on_exact
-		|is_intersecting,simplex|{
-			if is_intersecting{
-				return None;
-			}
-			// Convert simplex to FEV
-			// Vertices must be inverted since the mesh is inverted
-			Some(match simplex{
-				Simplex1_3::Simplex1([v0])=>FEV::Vert(-v0),
-				Simplex1_3::Simplex2([v0,v1])=>{
-					// invert
-					let (v0,v1)=(-v0,-v1);
-					let ev=crawl_to_closest_ev(mesh,[v0,v1],point);
-					if !matches!(ev,EV::Edge(_)){
-						println!("I can't believe it's not an edge!");
-					}
-					ev.into()
-				},
-				Simplex1_3::Simplex3([v0,v1,v2])=>{
-					// invert
-					let (v0,v1,v2)=(-v0,-v1,-v2);
-					// Shimmy to the side until you find a face that contains the closest point
-					// it's ALWAYS representable as a face, but this algorithm may
-					// return E or V in edge cases but I don't think that will break the face crawler
-					let fev=crawl_to_closest_fev(mesh,[v0,v1,v2],point);
-					if !matches!(fev,FEV::Face(_)){
-						println!("I can't believe it's not a face!");
-					}
-					fev
-				},
-			})
-		},
+		|_last_pos,_direction|unimplemented!(),
 		// on_escape
-		|_simplex|{
-			// intersection is guaranteed at this point
+		|simplex|{
 			// local norm, dist, u0, u1, v0, v1, w0, w1 = expand(queryP, queryQ, a0, a1, b0, b1, c0, c1, d0, d1, 1e-5)
-			// let simplex=refine_to_exact(mesh,simplex);
-			None
+			let simplex=refine_to_exact(mesh,simplex);
+			Topology{simplex}
 		},
 		// fast_fail value is irrelevant and will never be returned!
 		||unreachable!()
@@ -774,25 +582,25 @@ pub fn closest_fev_not_inside<'a>(mesh:&MinkowskiMesh<'a>,point:Planar64Vec3)->O
 // 	queryQ, radiusQ,
 // 	exitRadius, testIntersection
 // )
-fn minimum_difference<const ENABLE_FAST_FAIL:bool,T,M:MeshQuery>(
-	mesh:&M,
+fn minimum_difference<const ENABLE_FAST_FAIL:bool,T>(
+	mesh:&MinkowskiMesh,
 	point:Planar64Vec3,
-	on_exact:impl FnOnce(bool,Simplex1_3<M::Vert>)->T,
-	on_escape:impl FnOnce(Simplex<4,M::Vert>)->T,
+	on_exact:impl FnOnce(Planar64Vec3,Planar64Vec3)->T,
+	on_escape:impl FnOnce(Simplex<4>)->T,
 	on_fast_fail:impl FnOnce()->T,
 )->T{
 	// local initialAxis = queryQ() - queryP()
 	// local new_point_p = queryP(initialAxis)
 	// local new_point_q = queryQ(-initialAxis)
 	// local direction, a0, a1, b0, b1, c0, c1, d0, d1
-	let mut initial_axis=mesh.hint_point()+point;
+	let mut initial_axis=-mesh.hint_point()+point;
 	// degenerate case
 	if initial_axis==vec3::zero(){
 		initial_axis=choose_any_direction();
 	}
-	let last_point=mesh.farthest_vert(-initial_axis);
+	let last_point=mesh.farthest_vert(direction);
 	// this represents the 'a' value in the commented code
-	let mut last_pos=mesh.vert(last_point);
+	let mut last_pos=-mesh.vert(last_point);
 	let Reduced{dir:mut direction,simplex:mut simplex_small}=reduce1([last_point],mesh,point);
 
 	// exitRadius = testIntersection and 0 or exitRadius or 1/0
@@ -801,8 +609,8 @@ fn minimum_difference<const ENABLE_FAST_FAIL:bool,T,M:MeshQuery>(
 		// new_point_p = queryP(-direction)
 		// new_point_q = queryQ(direction)
 		// local next_point = new_point_q - new_point_p
-		let next_point=mesh.farthest_vert(direction);
-		let next_pos=mesh.vert(next_point);
+		let next_point=mesh.farthest_vert(-direction);
+		let next_pos=-mesh.vert(next_point);
 
 		// if -direction:Dot(next_point) > (exitRadius + radiusP + radiusQ)*direction.magnitude then
 		if ENABLE_FAST_FAIL&&direction.dot(next_pos+point).is_negative(){
@@ -817,11 +625,7 @@ fn minimum_difference<const ENABLE_FAST_FAIL:bool,T,M:MeshQuery>(
 		if !direction.dot(next_pos-last_pos).is_positive()
 		||simplex_big.det_is_zero(mesh){
 			// Found enough information to compute the exact closest point.
-			// local norm = direction.unit
-			// local dist = a:Dot(norm)
-			// local hits = -dist < radiusP + radiusQ
-			let is_intersecting=(last_pos+point).dot(direction).is_positive();
-			return on_exact(is_intersecting,simplex_small);
+			return on_exact(last_pos,direction);
 		}
 
 		// direction, a0, a1, b0, b1, c0, c1, d0, d1 = reduceSimplex(new_point_p, new_point_q, a0, a1, b0, b1, c0, c1)
@@ -842,41 +646,3 @@ fn minimum_difference<const ENABLE_FAST_FAIL:bool,T,M:MeshQuery>(
 		last_pos=next_pos;
 	}
 }
-
-#[cfg(test)]
-mod test{
-	use super::*;
-    use crate::model::{PhysicsMesh,PhysicsMeshView};
-
-    fn mesh_contains_point(mesh:PhysicsMeshView<'_>,point:Planar64Vec3)->bool{
-		const ENABLE_FAST_FAIL:bool=true;
-		// TODO: remove mesh negation
-		minimum_difference::<ENABLE_FAST_FAIL,_,_>(&mesh,point,
-			// on_exact
-			|is_intersecting,_simplex|{
-				is_intersecting
-			},
-			// on_escape
-			|_simplex|{
-				// intersection is guaranteed at this point
-				true
-			},
-			// fast_fail value
-			||false
-		)
-	}
-
-	#[test]
-	fn test_cube_points(){
-		let mesh=PhysicsMesh::unit_cube();
-		let mesh_view=mesh.complete_mesh_view();
-		for x in -2..=2{
-			for y in -2..=2{
-				for z in -2..=2{
-					let point=vec3::int(x,y,z)>>1;
-					assert!(mesh_contains_point(mesh_view,point),"Mesh did not contain point {point}");
-				}
-			}
-		}
-	}
-}

engine/physics/src/minimum_difference_lua.rs

@@ -12,9 +12,9 @@ pub fn contains_point(
 pub fn minimum_difference_details(
 	mesh:&MinkowskiMesh,
 	point:Planar64Vec3,
-)->LuaResult<(bool,Option<Details>)>{
+)->LuaResult<(bool,Details)>{
 	let md=minimum_difference(mesh,point,false)?;
-	Ok((md.hits,md.details))
+	Ok((md.hits,md.details.unwrap()))
 }
 fn p64v3(v:Vector)->Result<Planar64Vec3,FixedFromFloatError>{
 	Ok(Planar64Vec3::new([
@@ -65,23 +65,6 @@ impl FromLuaMulti for MinimumDifference{
 					q_norm:p64v3(q_norm).unwrap(),
 				}),
 			}),
-			&mut [
-				mlua::Value::Boolean(hits),
-				mlua::Value::Integer(distance),
-				mlua::Value::Vector(p_pos),
-				mlua::Value::Vector(p_norm),
-				mlua::Value::Vector(q_pos),
-				mlua::Value::Vector(q_norm),
-			]=>Ok(Self{
-				hits,
-				details:Some(Details{
-					distance:distance.into(),
-					p_pos:p64v3(p_pos).unwrap(),
-					p_norm:p64v3(p_norm).unwrap(),
-					q_pos:p64v3(q_pos).unwrap(),
-					q_norm:p64v3(q_norm).unwrap(),
-				}),
-			}),
 			values=>Err(mlua::Error::runtime(format!("Invalid return values: {values:?}"))),
 		}
 	}
@@ -92,6 +75,7 @@ struct Args{
 	radius_p:f64,
 	query_q:Function,
 	radius_q:f64,
+	exit_radius:f64,
 	test_intersection:bool,
 }
 impl Args{
@@ -103,6 +87,7 @@ impl Args{
 	)->LuaResult<Self>{
 		let radius_p=0.0;
 		let radius_q=0.0;
+		let exit_radius=0.0;
 		// Query the farthest point on the mesh in the given direction.
 		let query_p=lua.create_function(move|_,dir:Option<Vector>|{
 			let Some(dir)=dir else{
@@ -128,6 +113,7 @@ impl Args{
 			radius_p,
 			query_q,
 			radius_q,
+			exit_radius,
 			test_intersection,
 		})
 	}
@@ -140,7 +126,7 @@ impl IntoLuaMulti for Args{
 			self.radius_p.into_lua(lua)?,
 			self.query_q.into_lua(lua)?,
 			self.radius_q.into_lua(lua)?,
-			mlua::Value::Nil,
+			self.exit_radius.into_lua(lua)?,
 			self.test_intersection.into_lua(lua)?,
 		]))
 	}

engine/physics/src/model.rs

@@ -92,7 +92,6 @@ pub trait MeshQuery{
 	}
 	/// This must return a point inside the mesh.
 	fn hint_point(&self)->Planar64Vec3;
-	fn farthest_vert(&self,dir:Planar64Vec3)->Self::Vert;
 	fn vert(&self,vert_id:Self::Vert)->Planar64Vec3;
 	fn face_nd(&self,face_id:Self::Face)->(Self::Normal,Self::Offset);
 	fn face_edges(&self,face_id:Self::Face)->impl AsRef<[Self::Edge]>;
@@ -435,7 +434,7 @@ impl TryFrom<&model::Mesh> for PhysicsMesh{
 	}
 }
 
-#[derive(Debug,Clone,Copy)]
+#[derive(Debug)]
 pub struct PhysicsMeshView<'a>{
 	data:&'a PhysicsMeshData,
 	topology:&'a PhysicsMeshTopology,
@@ -454,18 +453,6 @@ impl MeshQuery for PhysicsMeshView<'_>{
 		// invariant: meshes always encompass the origin
 		vec3::zero()
 	}
-	fn farthest_vert(&self,dir:Planar64Vec3)->SubmeshVertId{
-		//this happens to be well-defined.  there are no virtual virtices
-		SubmeshVertId::new(
-			self.topology.verts.iter()
-			.enumerate()
-			.max_by_key(|&(_,&vert_id)|
-				dir.dot(self.data.verts[vert_id.get() as usize].0)
-			)
-			//assume there is more than zero vertices.
-			.unwrap().0 as u32
-		)
-	}
 	//ideally I never calculate the vertex position, but I have to for the graphical meshes...
 	fn vert(&self,vert_id:SubmeshVertId)->Planar64Vec3{
 		let vert_idx=self.topology.verts[vert_id.get() as usize].get() as usize;
@@ -504,7 +491,7 @@ impl PhysicsMeshTransform{
 	}
 }
 
-#[derive(Debug,Clone,Copy)]
+#[derive(Debug)]
 pub struct TransformedMesh<'a>{
 	view:PhysicsMeshView<'a>,
 	transform:&'a PhysicsMeshTransform,
@@ -522,6 +509,18 @@ impl TransformedMesh<'_>{
 	pub fn verts<'a>(&'a self)->impl Iterator<Item=Vector3<Fixed<2,64>>>+'a{
 		self.view.data.verts.iter().map(|&Vert(pos)|self.transform.vertex.transform_point3(pos))
 	}
+	pub fn farthest_vert(&self,dir:Planar64Vec3)->SubmeshVertId{
+		//this happens to be well-defined.  there are no virtual virtices
+		SubmeshVertId::new(
+			self.view.topology.verts.iter()
+			.enumerate()
+			.max_by_key(|&(_,&vert_id)|
+				dir.dot(self.transform.vertex.transform_point3(self.view.data.verts[vert_id.get() as usize].0))
+			)
+			//assume there is more than zero vertices.
+			.unwrap().0 as u32
+		)
+	}
 }
 impl MeshQuery for TransformedMesh<'_>{
 	type Face=SubmeshFaceId;
@@ -542,18 +541,6 @@ impl MeshQuery for TransformedMesh<'_>{
 	fn hint_point(&self)->Planar64Vec3{
 		self.transform.vertex.translation
 	}
-	fn farthest_vert(&self,dir:Planar64Vec3)->SubmeshVertId{
-		//this happens to be well-defined.  there are no virtual virtices
-		SubmeshVertId::new(
-			self.view.topology.verts.iter()
-			.enumerate()
-			.max_by_key(|&(_,&vert_id)|
-				dir.dot(self.transform.vertex.transform_point3(self.view.data.verts[vert_id.get() as usize].0))
-			)
-			//assume there is more than zero vertices.
-			.unwrap().0 as u32
-		)
-	}
 	#[inline]
 	fn face_edges(&self,face_id:SubmeshFaceId)->impl AsRef<[SubmeshDirectedEdgeId]>{
 		self.view.face_edges(face_id)
@@ -584,16 +571,7 @@ impl MeshQuery for TransformedMesh<'_>{
 pub enum MinkowskiVert{
 	VertVert(SubmeshVertId,SubmeshVertId),
 }
-// TODO: remove this
-impl core::ops::Neg for MinkowskiVert{
-	type Output=Self;
-	fn neg(self)->Self::Output{
-		match self{
-			MinkowskiVert::VertVert(v0,v1)=>MinkowskiVert::VertVert(v1,v0),
-		}
-	}
-}
-#[derive(Clone,Copy,Debug,Eq,PartialEq)]
+#[derive(Clone,Copy,Debug)]
 pub enum MinkowskiEdge{
 	VertEdge(SubmeshVertId,SubmeshEdgeId),
 	EdgeVert(SubmeshEdgeId,SubmeshVertId),
@@ -629,7 +607,7 @@ impl DirectedEdge for MinkowskiDirectedEdge{
 		}
 	}
 }
-#[derive(Clone,Copy,Debug,Hash)]
+#[derive(Clone,Copy,Debug,Hash,Eq,PartialEq)]
 pub enum MinkowskiFace{
 	VertFace(SubmeshVertId,SubmeshFaceId),
 	EdgeEdge(SubmeshEdgeId,SubmeshEdgeId,bool),
@@ -662,14 +640,6 @@ pub fn into_giga_time(time:Time,relative_to:Time)->GigaTime{
 	Ratio::new(r.num.widen_4(),r.den.widen_4())
 }
 
-// TODO: remove this
-impl<'a> core::ops::Neg for &MinkowskiMesh<'a>{
-	type Output=MinkowskiMesh<'a>;
-	fn neg(self)->Self::Output{
-		MinkowskiMesh::minkowski_sum(self.mesh1,self.mesh0)
-	}
-}
-
 impl MinkowskiMesh<'_>{
 	pub fn minkowski_sum<'a>(mesh0:TransformedMesh<'a>,mesh1:TransformedMesh<'a>)->MinkowskiMesh<'a>{
 		MinkowskiMesh{
@@ -677,7 +647,7 @@ impl MinkowskiMesh<'_>{
 			mesh1,
 		}
 	}
-	fn farthest_vert(&self,dir:Planar64Vec3)->MinkowskiVert{
+	pub fn farthest_vert(&self,dir:Planar64Vec3)->MinkowskiVert{
 		MinkowskiVert::VertVert(self.mesh0.farthest_vert(dir),self.mesh1.farthest_vert(-dir))
 	}
 	fn next_transition_vert(&self,vert_id:MinkowskiVert,best_distance_squared:&mut Fixed<2,64>,infinity_dir:Planar64Vec3,point:Planar64Vec3)->Transition{
@@ -795,23 +765,22 @@ impl MinkowskiMesh<'_>{
 		})
 	}
 	pub fn predict_collision_in(&self,relative_body:&Body,range:impl RangeBounds<Time>)->Option<(MinkowskiFace,GigaTime)>{
-		let old_fev=self.closest_fev_not_inside(*relative_body,range.start_bound());
-		let fev=crate::minimum_difference::closest_fev_not_inside(self,relative_body.position)?;
-		println!("old_fev={old_fev:?}");
-		println!("fev={fev:?}");
-		//continue forwards along the body parabola
-		fev.crawl(self,relative_body,range.start_bound(),range.end_bound()).hit()
+		self.closest_fev_not_inside(*relative_body,range.start_bound()).and_then(|fev|{
+			//continue forwards along the body parabola
+			fev.crawl(self,relative_body,range.start_bound(),range.end_bound()).hit()
+		})
 	}
 	pub fn predict_collision_out(&self,relative_body:&Body,range:impl RangeBounds<Time>)->Option<(MinkowskiFace,GigaTime)>{
-		let fev=crate::minimum_difference::closest_fev_not_inside(self,relative_body.position)?;
 		let (lower_bound,upper_bound)=(range.start_bound(),range.end_bound());
 		// swap and negate bounds to do a time inversion
 		let (lower_bound,upper_bound)=(upper_bound.map(|&t|-t),lower_bound.map(|&t|-t));
 		let infinity_body=-relative_body;
-		//continue backwards along the body parabola
-		fev.crawl(self,&infinity_body,lower_bound.as_ref(),upper_bound.as_ref()).hit()
-			//no need to test -time<time_limit because of the first step
-			.map(|(face,time)|(face,-time))
+		self.closest_fev_not_inside(infinity_body,lower_bound.as_ref()).and_then(|fev|{
+			//continue backwards along the body parabola
+			fev.crawl(self,&infinity_body,lower_bound.as_ref(),upper_bound.as_ref()).hit()
+				//no need to test -time<time_limit because of the first step
+				.map(|(face,time)|(face,-time))
+		})
 	}
 	pub fn predict_collision_face_out(&self,relative_body:&Body,range:impl RangeBounds<Time>,contact_face_id:MinkowskiFace)->Option<(MinkowskiDirectedEdge,GigaTime)>{
 		// TODO: make better
@@ -842,7 +811,10 @@ impl MinkowskiMesh<'_>{
 		best_edge
 	}
 	pub fn contains_point(&self,point:Planar64Vec3)->bool{
-		crate::minimum_difference::contains_point(self,point)
+		let contains_point_lua=crate::minimum_difference_lua::contains_point(self,point).unwrap();
+		let contains_point=crate::minimum_difference::contains_point(self,point);
+		println!("contains_point={contains_point} contains_point_lua={contains_point_lua}");
+		contains_point
 	}
 }
 impl MeshQuery for MinkowskiMesh<'_>{
@@ -884,9 +856,6 @@ impl MeshQuery for MinkowskiMesh<'_>{
 	fn hint_point(&self)->Planar64Vec3{
 		self.mesh0.transform.vertex.translation-self.mesh1.transform.vertex.translation
 	}
-	fn farthest_vert(&self,dir:Planar64Vec3)->MinkowskiVert{
-		MinkowskiVert::VertVert(self.mesh0.farthest_vert(dir),self.mesh1.farthest_vert(-dir))
-	}
 	fn face_edges(&self,face_id:MinkowskiFace)->impl AsRef<[MinkowskiDirectedEdge]>{
 		match face_id{
 			MinkowskiFace::VertFace(v0,f1)=>{

engine/physics/src/physics.rs

@@ -729,7 +729,7 @@ struct IntersectModel{
 	transform:PhysicsMeshTransform,
 }
 
-#[derive(Debug,Clone,Copy,Hash)]
+#[derive(Debug,Clone,Copy,Eq,Hash,PartialEq)]
 pub struct ContactCollision{
 	convex_mesh_id:ConvexMeshId<ContactModelId>,
 	face_id:model_physics::MinkowskiFace,
@@ -738,7 +738,7 @@ pub struct ContactCollision{
 pub struct IntersectCollision{
 	convex_mesh_id:ConvexMeshId<IntersectModelId>,
 }
-#[derive(Debug,Clone,Hash)]
+#[derive(Debug,Clone,Eq,Hash,PartialEq)]
 pub enum Collision{
 	Contact(ContactCollision),
 	Intersect(IntersectCollision),