idea

lib
defer body update to actual strafe tick
2026-01-28 12:22:02 -08:00 · 2026-01-28 12:21:46 -08:00 · 2026-01-28 09:57:33 -08:00 · 2026-01-28 08:40:14 -08:00 · 2026-01-28 08:39:28 -08:00 · 2026-01-28 07:28:22 -08:00
24 changed files with 1429 additions and 12694 deletions
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -813,6 +813,10 @@ version = "1.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f27ae1dd37df86211c42e150270f82743308803d90a6f6e6651cd730d5e1732f"

+[[package]]
+name = "dag"
+version = "0.1.0"
+
 [[package]]
 name = "ddsfile"
 version = "0.5.2"
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -7,6 +7,7 @@ members = [
 	"integration-testing",
 	"lib/bsp_loader",
 	"lib/common",
+	"lib/dag",
 	"lib/deferred_loader",
 	"lib/fixed_wide",
 	"lib/linear_ops",
--- a/engine/graphics/src/graphics.rs
+++ b/engine/graphics/src/graphics.rs
@@ -909,7 +909,7 @@ impl GraphicsState{

 		// update rotation
 		let camera_uniforms=self.camera.to_uniform_data(
-			frame_state.body.extrapolated_position(frame_state.time).map(Into::<f32>::into).to_array().into(),
+			frame_state.trajectory.extrapolated_position(frame_state.time).map(Into::<f32>::into).to_array().into(),
 			frame_state.camera.simulate_move_angles(glam::IVec2::ZERO)
 		);
 		self.staging_belt
--- a/engine/physics/src/body.rs
+++ b/engine/physics/src/body.rs
@@ -2,12 +2,18 @@ use strafesnet_common::aabb;
 use strafesnet_common::integer::{self,vec3,Time,Planar64,Planar64Vec3};
 #[derive(Clone,Copy,Debug,Hash)]
 pub struct Body<T>{
-	pub position:Planar64Vec3,//I64 where 2^32 = 1 u
-	pub velocity:Planar64Vec3,//I64 where 2^32 = 1 u/s
-	pub acceleration:Planar64Vec3,//I64 where 2^32 = 1 u/s/s
-	pub time:Time<T>,//nanoseconds x xxxxD!
+	pub position:Planar64Vec3,
+	pub velocity:Planar64Vec3,
+	pub time:Time<T>,
 }
-impl<T> std::ops::Neg for Body<T>{
+#[derive(Clone,Copy,Debug,Hash)]
+pub struct Trajectory<T>{
+	pub position:Planar64Vec3,
+	pub velocity:Planar64Vec3,
+	pub acceleration:Planar64Vec3,
+	pub time:Time<T>,
+}
+impl<T> std::ops::Neg for Trajectory<T>{
 	type Output=Self;
 	fn neg(self)->Self::Output{
 		Self{
@@ -18,10 +24,10 @@ impl<T> std::ops::Neg for Body<T>{
 		}
 	}
 }
-impl<T:Copy> std::ops::Neg for &Body<T>{
-	type Output=Body<T>;
+impl<T:Copy> std::ops::Neg for &Trajectory<T>{
+	type Output=Trajectory<T>;
 	fn neg(self)->Self::Output{
-		Body{
+		Trajectory{
 			position:self.position,
 			velocity:-self.velocity,
 			acceleration:self.acceleration,
@@ -32,6 +38,32 @@ impl<T:Copy> std::ops::Neg for &Body<T>{

 impl<T> Body<T>
 	where Time<T>:Copy,
+{
+	pub const ZERO:Self=Self::new(vec3::zero(),vec3::zero(),Time::ZERO);
+	pub const fn new(position:Planar64Vec3,velocity:Planar64Vec3,time:Time<T>)->Self{
+		Self{
+			position,
+			velocity,
+			time,
+		}
+	}
+	pub const fn with_acceleration(self,acceleration:Planar64Vec3)->Trajectory<T>{
+		let Body{
+			position,
+			velocity,
+			time,
+		}=self;
+		Trajectory{
+			position,
+			velocity,
+			acceleration,
+			time,
+		}
+	}
+}
+
+impl<T> Trajectory<T>
+	where Time<T>:Copy,
 {
 	pub const ZERO:Self=Self::new(vec3::zero(),vec3::zero(),vec3::zero(),Time::ZERO);
 	pub const fn new(position:Planar64Vec3,velocity:Planar64Vec3,acceleration:Planar64Vec3,time:Time<T>)->Self{
@@ -42,13 +74,14 @@ impl<T> Body<T>
 			time,
 		}
 	}
-	pub const fn relative_to<'a>(&'a self,body0:&'a Body<T>)->VirtualBody<'a,T>{
+	pub fn relative_to(&self,trj0:&Self,time:Time<T>)->Self{
 		//(p0,v0,a0,t0)
 		//(p1,v1,a1,t1)
-		VirtualBody{
-			body0,
-			body1:self,
-		}
+		Trajectory::new(
+			self.extrapolated_position(time)-trj0.extrapolated_position(time),
+			self.extrapolated_velocity(time)-trj0.extrapolated_velocity(time),
+			self.acceleration-trj0.acceleration,
+			time)
 	}
 	pub fn extrapolated_position(&self,time:Time<T>)->Planar64Vec3{
 		let dt=time-self.time;
@@ -60,10 +93,12 @@ impl<T> Body<T>
 		let dt=time-self.time;
 		self.velocity+(self.acceleration*dt).map(|elem|elem.divide().clamp_1())
 	}
-	pub fn advance_time(&mut self,time:Time<T>){
-		self.position=self.extrapolated_position(time);
-		self.velocity=self.extrapolated_velocity(time);
-		self.time=time;
+	pub fn extrapolated_body(&self,time:Time<T>)->Body<T>{
+		Body::new(
+			self.extrapolated_position(time),
+			self.extrapolated_velocity(time),
+			time,
+		)
 	}
 	pub fn extrapolated_position_ratio_dt<Num,Den,N1,D1,N2,N3,D2,N4,T1>(&self,dt:integer::Ratio<Num,Den>)->Planar64Vec3
 		where
@@ -101,10 +136,12 @@ impl<T> Body<T>
 		// a*dt + v
 		self.acceleration.map(|elem|(dt*elem).divide().clamp())+self.velocity
 	}
-	pub fn advance_time_ratio_dt(&mut self,dt:crate::model::GigaTime){
-		self.position=self.extrapolated_position_ratio_dt(dt);
-		self.velocity=self.extrapolated_velocity_ratio_dt(dt);
-		self.time+=dt.into();
+	pub fn extrapolated_body_ratio_dt(&self,dt:crate::model::GigaTime)->Body<T>{
+		Body::new(
+			self.extrapolated_position_ratio_dt(dt),
+			self.extrapolated_velocity_ratio_dt(dt),
+			self.time+dt.into(),
+		)
 	}
 	pub fn infinity_dir(&self)->Option<Planar64Vec3>{
 		if self.velocity==vec3::zero(){
@@ -144,28 +181,12 @@ impl<T> Body<T>

 }
 impl<T> std::fmt::Display for Body<T>{
+	fn fmt(&self,f:&mut std::fmt::Formatter<'_>)->std::fmt::Result{
+		write!(f,"p({}) v({}) t({})",self.position,self.velocity,self.time)
+	}
+}
+impl<T> std::fmt::Display for Trajectory<T>{
 	fn fmt(&self,f:&mut std::fmt::Formatter<'_>)->std::fmt::Result{
 		write!(f,"p({}) v({}) a({}) t({})",self.position,self.velocity,self.acceleration,self.time)
 	}
 }
-
-pub struct VirtualBody<'a,T>{
-	body0:&'a Body<T>,
-	body1:&'a Body<T>,
-}
-impl<T> VirtualBody<'_,T>
-	where Time<T>:Copy,
-{
-	pub fn extrapolated_position(&self,time:Time<T>)->Planar64Vec3{
-		self.body1.extrapolated_position(time)-self.body0.extrapolated_position(time)
-	}
-	pub fn extrapolated_velocity(&self,time:Time<T>)->Planar64Vec3{
-		self.body1.extrapolated_velocity(time)-self.body0.extrapolated_velocity(time)
-	}
-	pub fn acceleration(&self)->Planar64Vec3{
-		self.body1.acceleration-self.body0.acceleration
-	}
-	pub fn body(&self,time:Time<T>)->Body<T>{
-		Body::new(self.extrapolated_position(time),self.extrapolated_velocity(time),self.acceleration(),time)
-	}
-}
--- a/engine/physics/src/face_crawler.rs
+++ b/engine/physics/src/face_crawler.rs
@@ -1,6 +1,6 @@
 use crate::model::{into_giga_time,GigaTime,FEV,MeshQuery,DirectedEdge};
 use strafesnet_common::integer::{Fixed,Ratio,vec3::Vector3};
-use crate::physics::{Time,Body};
+use crate::physics::{Time,Trajectory};

 use core::ops::Bound;

@@ -21,12 +21,6 @@ impl<M:MeshQuery> CrawlResult<M>{
 			CrawlResult::Hit(face,time)=>Some((face,time)),
 		}
 	}
-	pub fn miss(self)->Option<FEV<M>>{
-		match self{
-			CrawlResult::Miss(fev)=>Some(fev),
-			CrawlResult::Hit(_,_)=>None,
-		}
-	}
 }

 // TODO: move predict_collision_face_out algorithm in here or something
@@ -80,7 +74,7 @@ impl<F:Copy,M:MeshQuery<Normal=Vector3<F>,Offset=Fixed<4,128>>> FEV<M>
 		<F as core::ops::Mul<Fixed<1,32>>>::Output:core::iter::Sum,
 		M::Offset:core::ops::Sub<<F as std::ops::Mul<Fixed<1,32>>>::Output>,
 {
-	fn next_transition(&self,mesh:&M,body:&Body,lower_bound:Bound<GigaTime>,mut upper_bound:Bound<GigaTime>)->Transition<M>{
+	fn next_transition(&self,mesh:&M,trajectory:&Trajectory,lower_bound:Bound<GigaTime>,mut upper_bound:Bound<GigaTime>)->Transition<M>{
 		//conflicting derivative means it crosses in the wrong direction.
 		//if the transition time is equal to an already tested transition, do not replace the current best.
 		let mut best_transition=Transition::Miss;
@@ -92,8 +86,8 @@ impl<F:Copy,M:MeshQuery<Normal=Vector3<F>,Offset=Fixed<4,128>>> FEV<M>
 				let (n,d)=mesh.face_nd(face_id);
 				//TODO: use higher precision d value?
 				//use the mesh transform translation instead of baking it into the d value.
-				for dt in Fixed::<4,128>::zeroes2((n.dot(body.position)-d)*2,n.dot(body.velocity)*2,n.dot(body.acceleration)){
-					if low(&lower_bound,&dt)&&upp(&dt,&upper_bound)&&n.dot(body.extrapolated_velocity_ratio_dt(dt)).is_negative(){
+				for dt in Fixed::<4,128>::zeroes2((n.dot(trajectory.position)-d)*2,n.dot(trajectory.velocity)*2,n.dot(trajectory.acceleration)){
+					if low(&lower_bound,&dt)&&upp(&dt,&upper_bound)&&n.dot(trajectory.extrapolated_velocity_ratio_dt(dt)).is_negative(){
 						upper_bound=Bound::Included(dt);
 						best_transition=Transition::Hit(face_id,dt);
 						break;
@@ -107,8 +101,8 @@ impl<F:Copy,M:MeshQuery<Normal=Vector3<F>,Offset=Fixed<4,128>>> FEV<M>
 					//WARNING: d is moved out of the *2 block because of adding two vertices!
 					//WARNING: precision is swept under the rug!
 					//wrap for speed
-					for dt in Fixed::<4,128>::zeroes2(n.dot(body.position*2-(mesh.vert(v0)+mesh.vert(v1))).wrap_4(),n.dot(body.velocity).wrap_4()*2,n.dot(body.acceleration).wrap_4()){
-						if low(&lower_bound,&dt)&&upp(&dt,&upper_bound)&&n.dot(body.extrapolated_velocity_ratio_dt(dt)).is_negative(){
+					for dt in Fixed::<4,128>::zeroes2(n.dot(trajectory.position*2-(mesh.vert(v0)+mesh.vert(v1))).wrap_4(),n.dot(trajectory.velocity).wrap_4()*2,n.dot(trajectory.acceleration).wrap_4()){
+						if low(&lower_bound,&dt)&&upp(&dt,&upper_bound)&&n.dot(trajectory.extrapolated_velocity_ratio_dt(dt)).is_negative(){
 							upper_bound=Bound::Included(dt);
 							best_transition=Transition::Next(FEV::Edge(directed_edge_id.as_undirected()),dt);
 							break;
@@ -123,15 +117,15 @@ impl<F:Copy,M:MeshQuery<Normal=Vector3<F>,Offset=Fixed<4,128>>> FEV<M>
 				let &[ev0,ev1]=edge_verts.as_ref();
 				let (v0,v1)=(mesh.vert(ev0),mesh.vert(ev1));
 				let edge_n=v1-v0;
-				let delta_pos=body.position*2-(v0+v1);
+				let delta_pos=trajectory.position*2-(v0+v1);
 				for (i,&edge_face_id) in mesh.edge_faces(edge_id).as_ref().iter().enumerate(){
 					let face_n=mesh.face_nd(edge_face_id).0;
 					//edge_n gets parity from the order of edge_faces
 					let n=face_n.cross(edge_n)*((i as i64)*2-1);
 					//WARNING yada yada d *2
 					//wrap for speed
-					for dt in Fixed::<4,128>::zeroes2(n.dot(delta_pos).wrap_4(),n.dot(body.velocity).wrap_4()*2,n.dot(body.acceleration).wrap_4()){
-						if low(&lower_bound,&dt)&&upp(&dt,&upper_bound)&&n.dot(body.extrapolated_velocity_ratio_dt(dt)).is_negative(){
+					for dt in Fixed::<4,128>::zeroes2(n.dot(delta_pos).wrap_4(),n.dot(trajectory.velocity).wrap_4()*2,n.dot(trajectory.acceleration).wrap_4()){
+						if low(&lower_bound,&dt)&&upp(&dt,&upper_bound)&&n.dot(trajectory.extrapolated_velocity_ratio_dt(dt)).is_negative(){
 							upper_bound=Bound::Included(dt);
 							best_transition=Transition::Next(FEV::Face(edge_face_id),dt);
 							break;
@@ -142,8 +136,8 @@ impl<F:Copy,M:MeshQuery<Normal=Vector3<F>,Offset=Fixed<4,128>>> FEV<M>
 				for (i,&vert_id) in edge_verts.as_ref().iter().enumerate(){
 					//vertex normal gets parity from vert index
 					let n=edge_n*(1-2*(i as i64));
-					for dt in Fixed::<2,64>::zeroes2((n.dot(body.position-mesh.vert(vert_id)))*2,n.dot(body.velocity)*2,n.dot(body.acceleration)){
-						if low(&lower_bound,&dt)&&upp(&dt,&upper_bound)&&n.dot(body.extrapolated_velocity_ratio_dt(dt)).is_negative(){
+					for dt in Fixed::<2,64>::zeroes2((n.dot(trajectory.position-mesh.vert(vert_id)))*2,n.dot(trajectory.velocity)*2,n.dot(trajectory.acceleration)){
+						if low(&lower_bound,&dt)&&upp(&dt,&upper_bound)&&n.dot(trajectory.extrapolated_velocity_ratio_dt(dt)).is_negative(){
 							let dt=Ratio::new(dt.num.widen_4(),dt.den.widen_4());
 							upper_bound=Bound::Included(dt);
 							best_transition=Transition::Next(FEV::Vert(vert_id),dt);
@@ -158,8 +152,8 @@ impl<F:Copy,M:MeshQuery<Normal=Vector3<F>,Offset=Fixed<4,128>>> FEV<M>
 				for &directed_edge_id in mesh.vert_edges(vert_id).as_ref(){
 					//edge is directed away from vertex, but we want the dot product to turn out negative
 					let n=-mesh.directed_edge_n(directed_edge_id);
-					for dt in Fixed::<2,64>::zeroes2((n.dot(body.position-mesh.vert(vert_id)))*2,n.dot(body.velocity)*2,n.dot(body.acceleration)){
-						if low(&lower_bound,&dt)&&upp(&dt,&upper_bound)&&n.dot(body.extrapolated_velocity_ratio_dt(dt)).is_negative(){
+					for dt in Fixed::<2,64>::zeroes2((n.dot(trajectory.position-mesh.vert(vert_id)))*2,n.dot(trajectory.velocity)*2,n.dot(trajectory.acceleration)){
+						if low(&lower_bound,&dt)&&upp(&dt,&upper_bound)&&n.dot(trajectory.extrapolated_velocity_ratio_dt(dt)).is_negative(){
 							let dt=Ratio::new(dt.num.widen_4(),dt.den.widen_4());
 							upper_bound=Bound::Included(dt);
 							best_transition=Transition::Next(FEV::Edge(directed_edge_id.as_undirected()),dt);
@@ -172,11 +166,11 @@ impl<F:Copy,M:MeshQuery<Normal=Vector3<F>,Offset=Fixed<4,128>>> FEV<M>
 		}
 		best_transition
 	}
-	pub fn crawl(mut self,mesh:&M,relative_body:&Body,lower_bound:Bound<&Time>,upper_bound:Bound<&Time>)->CrawlResult<M>{
-		let mut lower_bound=lower_bound.map(|&t|into_giga_time(t,relative_body.time));
-		let upper_bound=upper_bound.map(|&t|into_giga_time(t,relative_body.time));
+	pub fn crawl(mut self,mesh:&M,trajectory:&Trajectory,lower_bound:Bound<&Time>,upper_bound:Bound<&Time>)->CrawlResult<M>{
+		let mut lower_bound=lower_bound.map(|&t|into_giga_time(t,trajectory.time));
+		let upper_bound=upper_bound.map(|&t|into_giga_time(t,trajectory.time));
 		for _ in 0..20{
-			match self.next_transition(mesh,relative_body,lower_bound,upper_bound){
+			match self.next_transition(mesh,trajectory,lower_bound,upper_bound){
 				Transition::Miss=>return CrawlResult::Miss(self),
 				Transition::Next(next_fev,next_time)=>(self,lower_bound)=(next_fev,Bound::Included(next_time)),
 				Transition::Hit(face,time)=>return CrawlResult::Hit(face,time),
--- a/engine/physics/src/lib.rs
+++ b/engine/physics/src/lib.rs
@@ -1,7 +1,8 @@
 mod body;
-mod push_solve;
 mod face_crawler;
 mod model;
+mod push_solve;
+mod minimum_difference;

 pub mod physics;

--- a/engine/physics/src/minimum_difference.rs
+++ b/engine/physics/src/minimum_difference.rs
@@ -0,0 +1,895 @@
+use strafesnet_common::integer::vec3;
+use strafesnet_common::integer::vec3::Vector3;
+use strafesnet_common::integer::{Fixed,Planar64,Planar64Vec3};
+
+use crate::model::{DirectedEdge,FEV,MeshQuery};
+// TODO: remove mesh invert
+use crate::model::{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>),
+}
+impl<Vert> Simplex1_3<Vert>{
+	fn push_front(self,v:Vert)->Simplex2_4<Vert>{
+		match self{
+			Simplex1_3::Simplex1([v0])=>Simplex2_4::Simplex2([v,v0]),
+			Simplex1_3::Simplex2([v0,v1])=>Simplex2_4::Simplex3([v,v0,v1]),
+			Simplex1_3::Simplex3([v0,v1,v2])=>Simplex2_4::Simplex4([v,v0,v1,v2]),
+		}
+	}
+}
+#[derive(Clone,Copy)]
+enum Simplex2_4<Vert>{
+	Simplex2(Simplex<2,Vert>),
+	Simplex3(Simplex<3,Vert>),
+	Simplex4(Simplex<4,Vert>),
+}
+
+/*
+local function absDet(r, u, v, w)
+	if w then
+		return math.abs((u - r):Cross(v - r):Dot(w - r))
+	elseif v then
+		return (u - r):Cross(v - r).magnitude
+	elseif u then
+		return (u - r).magnitude
+	else
+		return 1
+	end
+end
+*/
+impl<Vert> Simplex2_4<Vert>{
+	fn det_is_zero<M:MeshQuery<Vert=Vert>>(self,mesh:&M)->bool{
+		match self{
+			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])=>{
+				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])=>{
+				let p0=mesh.vert(p0);
+				let p1=mesh.vert(p1);
+				p1-p0==vec3::zero()
+			}
+		}
+	}
+}
+
+/*
+local function choosePerpendicularDirection(d)
+	local x, y, z = d.x, d.y, d.z
+	local best = math.min(x*x, y*y, z*z)
+	if x*x == best then
+		return Vector3.new(y*y + z*z, -x*y, -x*z)
+	elseif y*y == best then
+		return Vector3.new(-x*y, x*x + z*z, -y*z)
+	else
+		return Vector3.new(-x*z, -y*z, x*x + y*y)
+	end
+end
+*/
+fn choose_perpendicular_direction(d:Planar64Vec3)->Planar64Vec3{
+	let x=d.x.abs();
+	let y=d.y.abs();
+	let z=d.z.abs();
+	if x<y&&x<z{
+		Vector3::new([Fixed::ZERO,-d.z,d.y])
+	}else if y<z{
+		Vector3::new([d.z,Fixed::ZERO,-d.x])
+	}else{
+		Vector3::new([-d.y,d.x,Fixed::ZERO])
+	}
+}
+
+const fn choose_any_direction()->Planar64Vec3{
+	vec3::X
+}
+
+fn narrow_dir2(dir:Vector3<Fixed<2,64>>)->Planar64Vec3{
+	if dir==vec3::zero(){
+		return dir.narrow_1().unwrap();
+	}
+	let x=dir.x.as_bits().unsigned_abs().bits();
+	let y=dir.y.as_bits().unsigned_abs().bits();
+	let z=dir.z.as_bits().unsigned_abs().bits();
+	let big=x.max(y).max(z);
+	const MAX_BITS:u32=64+31;
+	if MAX_BITS<big{
+		dir>>(big-MAX_BITS)
+	}else{
+		dir
+	}.narrow_1().unwrap()
+}
+fn narrow_dir3(dir:Vector3<Fixed<3,96>>)->Planar64Vec3{
+	if dir==vec3::zero(){
+		return dir.narrow_1().unwrap();
+	}
+	let x=dir.x.as_bits().unsigned_abs().bits();
+	let y=dir.y.as_bits().unsigned_abs().bits();
+	let z=dir.z.as_bits().unsigned_abs().bits();
+	let big=x.max(y).max(z);
+	const MAX_BITS:u32=96+31;
+	if MAX_BITS<big{
+		dir>>(big-MAX_BITS)
+	}else{
+		dir
+	}.narrow_1().unwrap()
+}
+
+fn reduce1<M:MeshQuery>(
+	[v0]:Simplex<1,M::Vert>,
+	mesh:&M,
+	point:Planar64Vec3,
+)->Reduced<M::Vert>{
+	// --debug.profilebegin("reduceSimplex0")
+	// local a = a1 - a0
+	let p0=mesh.vert(v0);
+
+	// local p = -a
+	let p=-(p0+point);
+
+	// local direction = p
+	let mut dir=p;
+
+	// if direction.magnitude == 0 then
+	// 	direction = chooseAnyDirection()
+	if dir==vec3::zero(){
+		dir=choose_any_direction();
+	}
+
+	// return direction, a0, a1
+	Reduced{
+		dir,
+		simplex:Simplex1_3::Simplex1([v0]),
+	}
+}
+
+// local function reduceSimplex1(a0, a1, b0, b1)
+fn reduce2<M:MeshQuery>(
+	[v0,v1]:Simplex<2,M::Vert>,
+	mesh:&M,
+	point:Planar64Vec3,
+)->Reduced<M::Vert>{
+	// --debug.profilebegin("reduceSimplex1")
+	// local a = a1 - a0
+	// local b = b1 - b0
+	let p0=mesh.vert(v0);
+	let p1=mesh.vert(v1);
+
+	// local p = -a
+	// local u = b - a
+	let p=-(p0+point);
+	let u=p1-p0;
+
+	// -- modify to take into account the radiuses
+	// local p_u = p:Dot(u)
+	let p_u=p.dot(u);
+
+	// if p_u >= 0 then
+	if !p_u.is_negative(){
+		// local direction = u:Cross(p):Cross(u)
+		let direction=u.cross(p).cross(u);
+
+		// if direction.magnitude == 0 then
+		if direction==vec3::zero(){
+			return Reduced{
+				dir:choose_perpendicular_direction(u),
+				simplex:Simplex1_3::Simplex2([v0,v1]),
+			};
+		}
+
+		// -- modify the direction to take into account a0R and b0R
+		// return direction, a0, a1, b0, b1
+		return Reduced{
+			dir:narrow_dir3(direction),
+			simplex:Simplex1_3::Simplex2([v0,v1]),
+		};
+	}
+
+	// local direction = p
+	let mut dir=p;
+
+	// if direction.magnitude == 0 then
+	if dir==vec3::zero(){
+		dir=choose_perpendicular_direction(u);
+	}
+
+	// return direction, a0, a1
+	Reduced{
+		dir,
+		simplex:Simplex1_3::Simplex1([v0]),
+	}
+}
+
+// local function reduceSimplex2(a0, a1, b0, b1, c0, c1)
+fn reduce3<M:MeshQuery>(
+	[v0,mut v1,v2]:Simplex<3,M::Vert>,
+	mesh:&M,
+	point:Planar64Vec3,
+)->Reduced<M::Vert>{
+	// --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);
+
+	// local p = -a
+	// local u = b - a
+	// local v = c - a
+	let p=-(p0+point);
+	let mut u=p1-p0;
+	let v=p2-p0;
+
+	// local uv = u:Cross(v)
+	// local up = u:Cross(p)
+	// local pv = p:Cross(v)
+	// local uv_up = uv:Dot(up)
+	// local uv_pv = uv:Dot(pv)
+	let mut uv=u.cross(v);
+	let mut up=u.cross(p);
+	let pv=p.cross(v);
+	let uv_up=uv.dot(up);
+	let uv_pv=uv.dot(pv);
+
+	// if uv_up >= 0 and uv_pv >= 0 then
+	if !uv_up.is_negative()&&!uv_pv.is_negative(){
+		// local uvp = uv:Dot(p)
+		let uvp=uv.dot(p);
+
+		// local direction = uvp < 0 and -uv or uv
+		let direction=if uvp.is_negative(){
+			-uv
+		}else{
+			uv
+		};
+
+		// return direction, a0, a1, b0, b1, c0, c1
+		return Reduced{
+			dir:narrow_dir2(direction),
+			simplex:Simplex1_3::Simplex3([v0,v1,v2]),
+		};
+	}
+
+	// local u_u = u:Dot(u)
+	// local v_v = v:Dot(v)
+	// local uDist = uv_up/(u_u*v.magnitude)
+	// local vDist = uv_pv/(v_v*u.magnitude)
+	// local minDist2 = math.min(uDist, vDist)
+	let u_dist=uv_up*v.length();
+	let v_dist=uv_pv*u.length();
+
+	// if vDist == minDist2 then
+	if v_dist<u_dist{
+		u=v;
+		up=-pv;
+		uv=-uv;
+		// b0 = c0
+		// b1 = c1
+		v1=v2;
+	}
+
+	// local p_u = p:Dot(u)
+	let p_u=p.dot(u);
+
+	// if p_u >= 0 then
+	if !p_u.is_negative(){
+		// local direction = up:Cross(u)
+		let direction=up.cross(u);
+		// if direction.magnitude == 0 then
+		if direction==vec3::zero(){
+			// direction = uv
+			return Reduced{
+				dir:narrow_dir2(uv),
+				simplex:Simplex1_3::Simplex2([v0,v1]),
+			};
+		}
+
+		// return direction, a0, a1, b0, b1
+		return Reduced{
+			dir:narrow_dir3(direction),
+			simplex:Simplex1_3::Simplex2([v0,v1]),
+		};
+	}
+
+	// local direction = p
+	let dir=p;
+	// if direction.magnitude == 0 then
+	if dir==vec3::zero(){
+		// direction = uv
+		return Reduced{
+			dir:narrow_dir2(uv),
+			simplex:Simplex1_3::Simplex1([v0]),
+		};
+	}
+	// return direction, a0, a0
+	Reduced{
+		dir,
+		simplex:Simplex1_3::Simplex1([v0]),
+	}
+}
+
+// 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,
+	point:Planar64Vec3,
+)->Reduce<M::Vert>{
+	// --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);
+
+	// local p = -a
+	// local u = b - a
+	// local v = c - a
+	// local w = d - a
+	let p=-(p0+point);
+	let mut u=p1-p0;
+	let mut v=p2-p0;
+	let w=p3-p0;
+
+	// local uv = u:Cross(v)
+	// local vw = v:Cross(w)
+	// local wu = w:Cross(u)
+	// local uvw = uv:Dot(w)
+	// local pvw = vw:Dot(p)
+	// local upw = wu:Dot(p)
+	// local uvp = uv:Dot(p)
+	let mut uv=u.cross(v);
+	let vw=v.cross(w);
+	let wu=w.cross(u);
+	let uv_w=uv.dot(w);
+	let pv_w=vw.dot(p);
+	let up_w=wu.dot(p);
+	let uv_p=uv.dot(p);
+
+	// if pvw/uvw >= 0 and upw/uvw >= 0 and uvp/uvw >= 0 then
+	if !pv_w.div_sign(uv_w).is_negative()
+	 &&!up_w.div_sign(uv_w).is_negative()
+	 &&!uv_p.div_sign(uv_w).is_negative(){
+		// origin is contained, this is a positive detection
+		// local direction = Vector3.new(0, 0, 0)
+		// return direction, a0, a1, b0, b1, c0, c1, d0, d1
+		return Reduce::Escape([v0,v1,v2,v3]);
+	}
+
+	// local uvwSign = uvw < 0 and -1 or uvw > 0 and 1 or 0
+	// local uvDist = uvp*uvwSign/uv.magnitude
+	// local vwDist = pvw*uvwSign/vw.magnitude
+	// local wuDist = upw*uvwSign/wu.magnitude
+	// local minDist3 = math.min(uvDist, vwDist, wuDist)
+	let uv_dist=uv_p.mul_sign(uv_w);
+	let vw_dist=pv_w.mul_sign(uv_w);
+	let wu_dist=up_w.mul_sign(uv_w);
+	let wu_len=wu.length();
+	let uv_len=uv.length();
+	let vw_len=vw.length();
+
+	if vw_dist*wu_len<wu_dist*vw_len{
+		// if vwDist == minDist3 then
+		if vw_dist*uv_len<uv_dist*vw_len{
+			(u,v)=(v,w);
+			uv=vw;
+			// uv_p=pv_w; // unused
+			// b0, c0 = c0, d0
+			// b1, c1 = c1, d1
+			(v1,v2)=(v2,v3);
+		}
+	}else{
+		// elseif wuDist == minDist3 then
+		if wu_dist*uv_len<uv_dist*wu_len{
+			(u,v)=(w,u);
+			uv=wu;
+			// uv_p=up_w; // unused
+			// b0, c0 = d0, b0
+			// b1, c1 = d1, b1
+			// before [a,b,c,d]
+			(v1,v2)=(v3,v1);
+			// after [a,d,b]
+		}
+	}
+
+	// local up = u:Cross(p)
+	// local pv = p:Cross(v)
+	// local uv_up = uv:Dot(up)
+	// local uv_pv = uv:Dot(pv)
+	let mut up=u.cross(p);
+	let pv=p.cross(v);
+	let uv_up=uv.dot(up);
+	let uv_pv=uv.dot(pv);
+
+	// if uv_up >= 0 and uv_pv >= 0 then
+	if !uv_up.is_negative()&&!uv_pv.is_negative(){
+		// local direction = uvw < 0 and uv or -uv
+		// return direction, a0, a1, b0, b1, c0, c1
+		let dir=if uv_w.is_negative(){
+			narrow_dir2(uv)
+		}else{
+			narrow_dir2(-uv)
+		};
+		return Reduce::Reduced(Reduced{
+			dir,
+			simplex:Simplex1_3::Simplex3([v0,v1,v2]),
+		});
+	}
+
+	// local u_u = u:Dot(u)
+	// local v_v = v:Dot(v)
+	// local uDist = uv_up/(u_u*v.magnitude)
+	// local vDist = uv_pv/(v_v*u.magnitude)
+	// local minDist2 = math.min(uDist, vDist)
+	let u_dist=uv_up*v.length();
+	let v_dist=uv_pv*u.length();
+
+	// if vDist == minDist2 then
+	if v_dist<u_dist{
+		u=v;
+		up=-pv;
+		uv=-uv;
+		// b0 = c0
+		// b1 = c1
+		v1=v2;
+	}
+
+	// local p_u = p:Dot(u)
+	let p_u=p.dot(u);
+
+	// if p_u >= 0 then
+	if !p_u.is_negative(){
+		// local direction = up:Cross(u)
+		let direction=up.cross(u);
+		// if direction.magnitude == 0 then
+		if direction==vec3::zero(){
+			// direction = uvw < 0 and uv or -uv
+			// return direction, a0, a1, b0, b1
+			let dir=if uv_w.is_negative(){
+				narrow_dir2(uv)
+			}else{
+				narrow_dir2(-uv)
+			};
+			return Reduce::Reduced(Reduced{
+				dir,
+				simplex:Simplex1_3::Simplex2([v0,v1]),
+			});
+		}
+
+		// return direction, a0, a1, b0, b1
+		return Reduce::Reduced(Reduced{
+			dir:narrow_dir3(direction),
+			simplex:Simplex1_3::Simplex2([v0,v1]),
+		});
+	}
+
+	// local direction = p
+	let dir=p;
+	// if direction.magnitude == 0 then
+	if dir==vec3::zero(){
+		// direction = uvw < 0 and uv or -uv
+		let dir=if uv_w.is_negative(){
+			narrow_dir2(uv)
+		}else{
+			narrow_dir2(-uv)
+		};
+		return Reduce::Reduced(Reduced{
+			dir,
+			simplex:Simplex1_3::Simplex1([v0]),
+		});
+	}
+
+	// return direction, a0, a1
+	Reduce::Reduced(Reduced{
+		dir,
+		simplex:Simplex1_3::Simplex1([v0]),
+	})
+}
+
+struct Reduced<Vert>{
+	dir:Planar64Vec3,
+	simplex:Simplex1_3<Vert>,
+}
+
+enum Reduce<Vert>{
+	Escape(Simplex<4,Vert>),
+	Reduced(Reduced<Vert>),
+}
+
+impl<Vert> Simplex2_4<Vert>{
+	fn reduce<M:MeshQuery<Vert=Vert>>(self,mesh:&M,point:Planar64Vec3)->Reduce<Vert>{
+		match self{
+			Self::Simplex2(simplex)=>Reduce::Reduced(reduce2(simplex,mesh,point)),
+			Self::Simplex3(simplex)=>Reduce::Reduced(reduce3(simplex,mesh,point)),
+			Self::Simplex4(simplex)=>reduce4(simplex,mesh,point),
+		}
+	}
+}
+
+//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 hops along parallel vertices until it finds the EV which contains the closest point to `point`.
+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 hops along connected vertices until it finds the FEV which contains the closest point to `point`.
+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>>>{
+	const ENABLE_FAST_FAIL:bool=false;
+	// TODO: remove mesh negation
+	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);
+					crawl_to_closest_ev(mesh,[v0,v1],point).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
+					crawl_to_closest_fev(mesh,[v0,v1,v2],point)
+				},
+			})
+		},
+		// on_escape
+		|_simplex|{
+			// intersection is guaranteed at this point
+			// 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
+		},
+		// fast_fail value is irrelevant and will never be returned!
+		||unreachable!()
+	)
+}
+
+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,
+		// on_exact
+		|is_intersecting,_simplex|{
+			is_intersecting
+		},
+		// on_escape
+		|_simplex|{
+			// intersection is guaranteed at this point
+			true
+		},
+		// fast_fail value
+		||false
+	)
+}
+
+// local function minimumDifference(
+// 	queryP, radiusP,
+// 	queryQ, radiusQ,
+// 	exitRadius, testIntersection
+// )
+fn minimum_difference<const ENABLE_FAST_FAIL:bool,T,M:MeshQuery>(
+	mesh:&M,
+	point:Planar64Vec3,
+	on_exact:impl FnOnce(bool,Simplex1_3<M::Vert>)->T,
+	on_escape:impl FnOnce(Simplex<4,M::Vert>)->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;
+	// degenerate case
+	if initial_axis==vec3::zero(){
+		initial_axis=choose_any_direction();
+	}
+	let last_point=mesh.farthest_vert(-initial_axis);
+	// this represents the 'a' value in the commented code
+	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
+	// for _ = 1, 100 do
+	loop{
+		// 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);
+
+		// if -direction:Dot(next_point) > (exitRadius + radiusP + radiusQ)*direction.magnitude then
+		if ENABLE_FAST_FAIL&&direction.dot(next_pos+point).is_negative(){
+			return on_fast_fail();
+		}
+
+		let simplex_big=simplex_small.push_front(next_point);
+
+		// if
+		// 	direction:Dot(next_point - a) <= 0 or
+		// 	absDet(next_point, a, b, c) < 1e-6
+		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);
+		}
+
+		// direction, a0, a1, b0, b1, c0, c1, d0, d1 = reduceSimplex(new_point_p, new_point_q, a0, a1, b0, b1, c0, c1)
+		match simplex_big.reduce(mesh,point){
+			// if a and b and c and d then
+			Reduce::Escape(simplex)=>{
+				// Enough information to conclude that the meshes are intersecting.
+				// Topology information is computed if needed.
+				return on_escape(simplex);
+			},
+			Reduce::Reduced(reduced)=>{
+				direction=reduced.dir;
+				simplex_small=reduced.simplex;
+			},
+		}
+
+		// next loop this will be a
+		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}");
+				}
+			}
+		}
+	}
+}
--- a/engine/physics/src/model.rs
+++ b/engine/physics/src/model.rs
@@ -5,7 +5,7 @@ use strafesnet_common::model::{self,MeshId,PolygonIter};
 use strafesnet_common::integer::{self,vec3,Fixed,Planar64,Planar64Vec3,Ratio};
 use strafesnet_common::physics::Time;

-type Body=crate::body::Body<strafesnet_common::physics::TimeInner>;
+type Trajectory=crate::body::Trajectory<strafesnet_common::physics::TimeInner>;

 struct AsRefHelper<T>(T);
 impl<T> AsRef<T> for AsRefHelper<T>{
@@ -16,14 +16,14 @@ impl<T> AsRef<T> for AsRefHelper<T>{

 pub trait UndirectedEdge{
 	type DirectedEdge:Copy+DirectedEdge;
-	fn as_directed(&self,parity:bool)->Self::DirectedEdge;
+	fn as_directed(self,parity:bool)->Self::DirectedEdge;
 }
-pub trait DirectedEdge{
+pub trait DirectedEdge:Copy{
 	type UndirectedEdge:Copy+std::fmt::Debug+UndirectedEdge;
-	fn as_undirected(&self)->Self::UndirectedEdge;
+	fn as_undirected(self)->Self::UndirectedEdge;
 	fn parity(&self)->bool;
 	//this is stupid but may work fine
-	fn reverse(&self)-><<Self as DirectedEdge>::UndirectedEdge as UndirectedEdge>::DirectedEdge{
+	fn reverse(self)-><<Self as DirectedEdge>::UndirectedEdge as UndirectedEdge>::DirectedEdge{
 		self.as_undirected().as_directed(!self.parity())
 	}
 }
@@ -45,13 +45,13 @@ pub struct SubmeshFaceId(u32);

 impl UndirectedEdge for SubmeshEdgeId{
 	type DirectedEdge=SubmeshDirectedEdgeId;
-	fn as_directed(&self,parity:bool)->SubmeshDirectedEdgeId{
+	fn as_directed(self,parity:bool)->SubmeshDirectedEdgeId{
 		SubmeshDirectedEdgeId(self.0|((parity as u32)<<(u32::BITS-1)))
 	}
 }
 impl DirectedEdge for SubmeshDirectedEdgeId{
 	type UndirectedEdge=SubmeshEdgeId;
-	fn as_undirected(&self)->SubmeshEdgeId{
+	fn as_undirected(self)->SubmeshEdgeId{
 		SubmeshEdgeId(self.0&!(1<<(u32::BITS-1)))
 	}
 	fn parity(&self)->bool{
@@ -91,8 +91,8 @@ pub trait MeshQuery{
 		(self.vert(v1)-self.vert(v0))*((directed_edge_id.parity() as i64)*2-1)
 	}
 	/// This must return a point inside the mesh.
-	#[expect(dead_code)]
 	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]>;
@@ -439,7 +439,7 @@ impl TryFrom<&model::Mesh> for PhysicsMesh{
 	}
 }

-#[derive(Debug)]
+#[derive(Debug,Clone,Copy)]
 pub struct PhysicsMeshView<'a>{
 	data:&'a PhysicsMeshData,
 	topology:&'a PhysicsMeshTopology,
@@ -458,6 +458,18 @@ 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;
@@ -496,7 +508,7 @@ impl PhysicsMeshTransform{
 	}
 }

-#[derive(Debug)]
+#[derive(Debug,Clone,Copy)]
 pub struct TransformedMesh<'a>{
 	view:PhysicsMeshView<'a>,
 	transform:&'a PhysicsMeshTransform,
@@ -514,18 +526,6 @@ 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))
 	}
-	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;
@@ -546,6 +546,18 @@ 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)
@@ -572,10 +584,19 @@ impl MeshQuery for TransformedMesh<'_>{
 //(face,vertex)
 //(edge,edge)
 //(vertex,face)
-#[derive(Clone,Copy,Debug)]
+#[derive(Clone,Copy,Debug,Eq,PartialEq)]
 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)]
 pub enum MinkowskiEdge{
 	VertEdge(SubmeshVertId,SubmeshEdgeId),
@@ -584,10 +605,10 @@ pub enum MinkowskiEdge{
 }
 impl UndirectedEdge for MinkowskiEdge{
 	type DirectedEdge=MinkowskiDirectedEdge;
-	fn as_directed(&self,parity:bool)->Self::DirectedEdge{
+	fn as_directed(self,parity:bool)->Self::DirectedEdge{
 		match self{
-			MinkowskiEdge::VertEdge(v0,e1)=>MinkowskiDirectedEdge::VertEdge(*v0,e1.as_directed(parity)),
-			MinkowskiEdge::EdgeVert(e0,v1)=>MinkowskiDirectedEdge::EdgeVert(e0.as_directed(parity),*v1),
+			MinkowskiEdge::VertEdge(v0,e1)=>MinkowskiDirectedEdge::VertEdge(v0,e1.as_directed(parity)),
+			MinkowskiEdge::EdgeVert(e0,v1)=>MinkowskiDirectedEdge::EdgeVert(e0.as_directed(parity),v1),
 		}
 	}
 }
@@ -599,10 +620,10 @@ pub enum MinkowskiDirectedEdge{
 }
 impl DirectedEdge for MinkowskiDirectedEdge{
 	type UndirectedEdge=MinkowskiEdge;
-	fn as_undirected(&self)->Self::UndirectedEdge{
+	fn as_undirected(self)->Self::UndirectedEdge{
 		match self{
-			MinkowskiDirectedEdge::VertEdge(v0,e1)=>MinkowskiEdge::VertEdge(*v0,e1.as_undirected()),
-			MinkowskiDirectedEdge::EdgeVert(e0,v1)=>MinkowskiEdge::EdgeVert(e0.as_undirected(),*v1),
+			MinkowskiDirectedEdge::VertEdge(v0,e1)=>MinkowskiEdge::VertEdge(v0,e1.as_undirected()),
+			MinkowskiDirectedEdge::EdgeVert(e0,v1)=>MinkowskiEdge::EdgeVert(e0.as_undirected(),v1),
 		}
 	}
 	fn parity(&self)->bool{
@@ -612,7 +633,7 @@ impl DirectedEdge for MinkowskiDirectedEdge{
 		}
 	}
 }
-#[derive(Clone,Copy,Debug,Hash,Eq,PartialEq)]
+#[derive(Clone,Copy,Debug,Hash)]
 pub enum MinkowskiFace{
 	VertFace(SubmeshVertId,SubmeshFaceId),
 	EdgeEdge(SubmeshEdgeId,SubmeshEdgeId,bool),
@@ -628,23 +649,20 @@ pub struct MinkowskiMesh<'a>{
 	mesh1:TransformedMesh<'a>,
 }

-//infinity fev algorithm state transition
-#[derive(Debug)]
-enum Transition{
-	Done,//found closest vert, no edges are better
-	Vert(MinkowskiVert),//transition to vert
-}
-enum EV{
-	Vert(MinkowskiVert),
-	Edge(MinkowskiEdge),
-}
-
 pub type GigaTime=Ratio<Fixed<4,128>,Fixed<4,128>>;
 pub fn into_giga_time(time:Time,relative_to:Time)->GigaTime{
 	let r=(time-relative_to).to_ratio();
 	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{
@@ -652,148 +670,40 @@ impl MinkowskiMesh<'_>{
 			mesh1,
 		}
 	}
-	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{
-		let mut best_transition=Transition::Done;
-		for &directed_edge_id in self.vert_edges(vert_id).as_ref(){
-			let edge_n=self.directed_edge_n(directed_edge_id);
-			//is boundary uncrossable by a crawl from infinity
-			let edge_verts=self.edge_verts(directed_edge_id.as_undirected());
-			//select opposite vertex
-			let test_vert_id=edge_verts.as_ref()[directed_edge_id.parity() as usize];
-			//test if it's closer
-			let diff=point-self.vert(test_vert_id);
-			if edge_n.dot(infinity_dir).is_zero(){
-				let distance_squared=diff.dot(diff);
-				if distance_squared<*best_distance_squared{
-					best_transition=Transition::Vert(test_vert_id);
-					*best_distance_squared=distance_squared;
-				}
-			}
-		}
-		best_transition
-	}
-	fn final_ev(&self,vert_id:MinkowskiVert,best_distance_squared:&mut Fixed<2,64>,infinity_dir:Planar64Vec3,point:Planar64Vec3)->EV{
-		let mut best_transition=EV::Vert(vert_id);
-		let diff=point-self.vert(vert_id);
-		for &directed_edge_id in self.vert_edges(vert_id).as_ref(){
-			let edge_n=self.directed_edge_n(directed_edge_id);
-			//is boundary uncrossable by a crawl from infinity
-			//check if time of collision is outside Time::MIN..Time::MAX
-			if edge_n.dot(infinity_dir).is_zero(){
-				let d=edge_n.dot(diff);
-				//test the edge
-				let edge_nn=edge_n.dot(edge_n);
-				if !d.is_negative()&&d<=edge_nn{
-					let distance_squared={
-						let c=diff.cross(edge_n);
-						//wrap for speed
-						(c.dot(c)/edge_nn).divide().wrap_2()
-					};
-					if distance_squared<=*best_distance_squared{
-						best_transition=EV::Edge(directed_edge_id.as_undirected());
-						*best_distance_squared=distance_squared;
-					}
-				}
-			}
-		}
-		best_transition
-	}
-	fn crawl_boundaries(&self,mut vert_id:MinkowskiVert,infinity_dir:Planar64Vec3,point:Planar64Vec3)->EV{
-		let mut best_distance_squared={
-			let diff=point-self.vert(vert_id);
-			diff.dot(diff)
+	pub fn predict_collision_in(&self,trajectory:&Trajectory,range:impl RangeBounds<Time>)->Option<(MinkowskiFace,GigaTime)>{
+		let start_position=match range.start_bound(){
+			Bound::Included(time)=>trajectory.extrapolated_position(*time),
+			Bound::Excluded(time)=>trajectory.extrapolated_position(*time),
+			Bound::Unbounded=>trajectory.position,
 		};
-		loop{
-			match self.next_transition_vert(vert_id,&mut best_distance_squared,infinity_dir,point){
-				Transition::Done=>return self.final_ev(vert_id,&mut best_distance_squared,infinity_dir,point),
-				Transition::Vert(new_vert_id)=>vert_id=new_vert_id,
-			}
-		}
+		let fev=crate::minimum_difference::closest_fev_not_inside(self,start_position)?;
+		//continue forwards along the body parabola
+		fev.crawl(self,trajectory,range.start_bound(),range.end_bound()).hit()
 	}
-	/// 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 infinity_fev(&self,infinity_dir:Planar64Vec3,point:Planar64Vec3)->FEV::<MinkowskiMesh<'_>>{
-		//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 self.crawl_boundaries(self.farthest_vert(infinity_dir),infinity_dir,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 the boundary is not crossable and we are on the wrong side
-				let edge_n=self.edge_n(edge_id);
-				// point is multiplied by two because vert_sum sums two vertices.
-				let delta_pos=point*2-{
-					let &[v0,v1]=self.edge_verts(edge_id).as_ref();
-					self.vert(v0)+self.vert(v1)
-				};
-				for (i,&face_id) in self.edge_faces(edge_id).as_ref().iter().enumerate(){
-					let face_n=self.face_nd(face_id).0;
-					//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);
-					//check if time of collision is outside Time::MIN..Time::MAX
-					//infinity_dir can always be treated as a velocity
-					if !boundary_d.is_positive()&&boundary_n.dot(infinity_dir).is_zero(){
-						//both faces cannot pass this condition, return early if one does.
-						return FEV::Face(face_id);
-					}
-				}
-				FEV::Edge(edge_id)
-			},
-		}
-	}
-	// TODO: fundamentally improve this algorithm.
-	// All it needs to do is find the closest point on the mesh
-	// and return the FEV which the point resides on.
-	//
-	// What it actually does is use the above functions to trace a ray in from infinity,
-	// crawling the closest point along the mesh surface until the ray reaches
-	// the starting point to discover the final FEV.
-	//
-	// The actual collision prediction probably does a single test
-	// and then immediately returns with 0 FEV transitions on average,
-	// because of the strict time_limit constraint.
-	//
-	// Most of the calculation time is just calculating the starting point
-	// for the "actual" crawling algorithm below (predict_collision_{in|out}).
-	fn closest_fev_not_inside(&self,mut infinity_body:Body,start_time:Bound<&Time>)->Option<FEV<MinkowskiMesh<'_>>>{
-		infinity_body.infinity_dir().and_then(|dir|{
-			let infinity_fev=self.infinity_fev(-dir,infinity_body.position);
-			//a line is simpler to solve than a parabola
-			infinity_body.velocity=dir;
-			infinity_body.acceleration=vec3::zero();
-			//crawl in from negative infinity along a tangent line to get the closest fev
-			infinity_fev.crawl(self,&infinity_body,Bound::Unbounded,start_time).miss()
-		})
-	}
-	pub fn predict_collision_in(&self,relative_body:&Body,range:impl RangeBounds<Time>)->Option<(MinkowskiFace,GigaTime)>{
-		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)>{
+	pub fn predict_collision_out(&self,trajectory:&Trajectory,range:impl RangeBounds<Time>)->Option<(MinkowskiFace,GigaTime)>{
 		let (lower_bound,upper_bound)=(range.start_bound(),range.end_bound());
+		// TODO: handle unbounded collision using infinity fev
+		let start_position=match upper_bound{
+			Bound::Included(time)=>trajectory.extrapolated_position(*time),
+			Bound::Excluded(time)=>trajectory.extrapolated_position(*time),
+			Bound::Unbounded=>trajectory.position,
+		};
+		let fev=crate::minimum_difference::closest_fev_not_inside(self,start_position)?;
 		// 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;
-		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))
-		})
+		let time_reversed_trajectory=-trajectory;
+		//continue backwards along the body parabola
+		fev.crawl(self,&time_reversed_trajectory,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)>{
+	pub fn predict_collision_face_out(&self,trajectory:&Trajectory,range:impl RangeBounds<Time>,contact_face_id:MinkowskiFace)->Option<(MinkowskiDirectedEdge,GigaTime)>{
 		// TODO: make better
 		use crate::face_crawler::{low,upp};
 		//no algorithm needed, there is only one state and two cases (Edge,None)
 		//determine when it passes an edge ("sliding off" case)
-		let start_time=range.start_bound().map(|&t|(t-relative_body.time).to_ratio());
-		let mut best_time=range.end_bound().map(|&t|into_giga_time(t,relative_body.time));
+		let start_time=range.start_bound().map(|&t|(t-trajectory.time).to_ratio());
+		let mut best_time=range.end_bound().map(|&t|into_giga_time(t,trajectory.time));
 		let mut best_edge=None;
 		let face_n=self.face_nd(contact_face_id).0;
 		for &directed_edge_id in self.face_edges(contact_face_id).as_ref(){
@@ -805,8 +715,8 @@ impl MinkowskiMesh<'_>{
 			//WARNING! d outside of *2
 			//WARNING: truncated precision
 			//wrap for speed
-			for dt in Fixed::<4,128>::zeroes2(((n.dot(relative_body.position))*2-d).wrap_4(),n.dot(relative_body.velocity).wrap_4()*2,n.dot(relative_body.acceleration).wrap_4()){
-				if low(&start_time,&dt)&&upp(&dt,&best_time)&&n.dot(relative_body.extrapolated_velocity_ratio_dt(dt)).is_negative(){
+			for dt in Fixed::<4,128>::zeroes2(((n.dot(trajectory.position))*2-d).wrap_4(),n.dot(trajectory.velocity).wrap_4()*2,n.dot(trajectory.acceleration).wrap_4()){
+				if low(&start_time,&dt)&&upp(&dt,&best_time)&&n.dot(trajectory.extrapolated_velocity_ratio_dt(dt)).is_negative(){
 					best_time=Bound::Included(dt);
 					best_edge=Some((directed_edge_id,dt));
 					break;
@@ -815,20 +725,8 @@ impl MinkowskiMesh<'_>{
 		}
 		best_edge
 	}
-	fn infinity_in(&self,infinity_body:Body)->Option<(MinkowskiFace,GigaTime)>{
-		let infinity_fev=self.infinity_fev(-infinity_body.velocity,infinity_body.position);
-		// Bound::Included means that the surface of the mesh is included in the mesh
-		infinity_fev.crawl(self,&infinity_body,Bound::Unbounded,Bound::Included(&infinity_body.time)).hit()
-	}
-	pub fn is_point_in_mesh(&self,point:Planar64Vec3)->bool{
-		let infinity_body=Body::new(point,vec3::Y,vec3::zero(),Time::ZERO);
-		//movement must escape the mesh forwards and backwards in time,
-		//otherwise the point is not inside the mesh
-		self.infinity_in(infinity_body)
-    	.is_some_and(|_|
-			self.infinity_in(-infinity_body)
-    		.is_some()
-     	)
+	pub fn contains_point(&self,point:Planar64Vec3)->bool{
+		crate::minimum_difference::contains_point(self,point)
 	}
 }
 impl MeshQuery for MinkowskiMesh<'_>{
@@ -868,8 +766,10 @@ impl MeshQuery for MinkowskiMesh<'_>{
 		}
 	}
 	fn hint_point(&self)->Planar64Vec3{
-		self.mesh1.transform.vertex.translation-
-		self.mesh0.transform.vertex.translation
+		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{
--- a/engine/physics/src/physics.rs
+++ b/engine/physics/src/physics.rs
@@ -15,6 +15,7 @@ pub use strafesnet_common::physics::{Time,TimeInner};
 use gameplay::ModeState;

 pub type Body=crate::body::Body<TimeInner>;
+pub type Trajectory=crate::body::Trajectory<TimeInner>;
 type MouseState=strafesnet_common::mouse::MouseState<TimeInner>;

 //external influence
@@ -28,6 +29,7 @@ pub enum InternalInstruction{
 	CollisionStart(Collision,model_physics::GigaTime),
 	CollisionEnd(Collision,model_physics::GigaTime),
 	StrafeTick,
+	// TODO: add GigaTime to ReachWalkTargetVelocity
 	ReachWalkTargetVelocity,
 	// Water,
 }
@@ -498,20 +500,24 @@ enum MoveState{
 }
 impl MoveState{
 	//call this after state.move_state is changed
-	fn apply_enum(&self,body:&mut Body,touching:&TouchingState,models:&PhysicsModels,hitbox_mesh:&HitboxMesh,style:&StyleModifiers,camera:&PhysicsCamera,input_state:&InputState){
+	fn acceleration(&self,touching:&TouchingState,models:&PhysicsModels,hitbox_mesh:&HitboxMesh,style:&StyleModifiers,camera:&PhysicsCamera,input_state:&InputState)->Planar64Vec3{
 		match self{
-			MoveState::Fly=>body.acceleration=vec3::zero(),
-			MoveState::Air=>{
-				//calculate base acceleration
-				let a=touching.base_acceleration(models,style,camera,input_state);
-				//set_acceleration clips according to contacts
-				set_acceleration(body,touching,models,hitbox_mesh,a);
+			MoveState::Fly=>vec3::zero(),
+			MoveState::Air
+			|MoveState::Water
+			=>{
+				// calculate base acceleration
+				let base_acceleration=touching.base_acceleration(models,style,camera,input_state);
+				// constrain_acceleration clips according to contacts
+				touching.constrain_acceleration(models,hitbox_mesh,base_acceleration)
 			},
-			_=>(),
+			MoveState::Walk(walk_state)
+			|MoveState::Ladder(walk_state)
+			=>walk_state.target.acceleration(),
 		}
 	}
 	//function to coerce &mut self into &self
-	fn apply_to_body(&self,body:&mut Body,touching:&TouchingState,models:&PhysicsModels,hitbox_mesh:&HitboxMesh,style:&StyleModifiers,camera:&PhysicsCamera,input_state:&InputState){
+	fn update_fly_velocity(&self,body:&mut Body,touching:&TouchingState,models:&PhysicsModels,hitbox_mesh:&HitboxMesh,style:&StyleModifiers,camera:&PhysicsCamera,input_state:&InputState){
 		match self{
 			MoveState::Air=>(),
 			MoveState::Water=>(),
@@ -521,17 +527,13 @@ impl MoveState{
 				//set_velocity clips velocity according to current touching state
 				set_velocity(body,touching,models,hitbox_mesh,v);
 			},
-			MoveState::Walk(walk_state)
-			|MoveState::Ladder(walk_state)
-			=>{
-				//accelerate towards walk target or do nothing
-				let a=walk_state.target.acceleration();
-				set_acceleration(body,touching,models,hitbox_mesh,a);
-			},
+			MoveState::Walk(_walk_state)
+			|MoveState::Ladder(_walk_state)
+			=>(),
 		}
 	}
 	/// changes the move state
-	fn apply_input(&mut self,body:&Body,touching:&TouchingState,models:&PhysicsModels,hitbox_mesh:&HitboxMesh,style:&StyleModifiers,camera:&PhysicsCamera,input_state:&InputState){
+	fn update_walk_target(&mut self,body:&Body,touching:&TouchingState,models:&PhysicsModels,hitbox_mesh:&HitboxMesh,style:&StyleModifiers,camera:&PhysicsCamera,input_state:&InputState){
 		match self{
 			MoveState::Fly
 			|MoveState::Air
@@ -588,24 +590,11 @@ impl MoveState{
 			MoveState::Fly=>None,
 		}
 	}
-	//lmao idk this is convenient
-	fn apply_enum_and_input_and_body(&mut self,body:&mut Body,touching:&TouchingState,models:&PhysicsModels,hitbox_mesh:&HitboxMesh,style:&StyleModifiers,camera:&PhysicsCamera,input_state:&InputState){
-		self.apply_enum(body,touching,models,hitbox_mesh,style,camera,input_state);
-		self.apply_input(body,touching,models,hitbox_mesh,style,camera,input_state);
-		self.apply_to_body(body,touching,models,hitbox_mesh,style,camera,input_state);
-	}
-	fn apply_enum_and_body(&mut self,body:&mut Body,touching:&TouchingState,models:&PhysicsModels,hitbox_mesh:&HitboxMesh,style:&StyleModifiers,camera:&PhysicsCamera,input_state:&InputState){
-		self.apply_enum(body,touching,models,hitbox_mesh,style,camera,input_state);
-		self.apply_to_body(body,touching,models,hitbox_mesh,style,camera,input_state);
-	}
-	fn apply_input_and_body(&mut self,body:&mut Body,touching:&TouchingState,models:&PhysicsModels,hitbox_mesh:&HitboxMesh,style:&StyleModifiers,camera:&PhysicsCamera,input_state:&InputState){
-		self.apply_input(body,touching,models,hitbox_mesh,style,camera,input_state);
-		self.apply_to_body(body,touching,models,hitbox_mesh,style,camera,input_state);
-	}
 	fn set_move_state(&mut self,move_state:MoveState,body:&mut Body,touching:&TouchingState,models:&PhysicsModels,hitbox_mesh:&HitboxMesh,style:&StyleModifiers,camera:&PhysicsCamera,input_state:&InputState){
 		*self=move_state;
 		//this function call reads the above state that was just set
-		self.apply_enum_and_body(body,touching,models,hitbox_mesh,style,camera,input_state);
+		self.update_walk_target(body,touching,models,hitbox_mesh,style,camera,input_state);
+		self.update_fly_velocity(body,touching,models,hitbox_mesh,style,camera,input_state);
 	}
 	fn cull_velocity(&mut self,velocity:Planar64Vec3,body:&mut Body,touching:&mut TouchingState,models:&PhysicsModels,hitbox_mesh:&HitboxMesh,style:&StyleModifiers,camera:&PhysicsCamera,input_state:&InputState){
 		//TODO: be more precise about contacts
@@ -618,10 +607,11 @@ impl MoveState{
 					self.set_move_state(MoveState::Air,body,touching,models,hitbox_mesh,style,camera,input_state);
 				}else{
 					// stopped touching something else while walking
-					self.apply_enum_and_input_and_body(body,touching,models,hitbox_mesh,style,camera,input_state);
+					self.update_walk_target(body,touching,models,hitbox_mesh,style,camera,input_state);
+					self.update_fly_velocity(body,touching,models,hitbox_mesh,style,camera,input_state);
 				},
 				// not walking, but stopped touching something
-				None=>self.apply_enum_and_body(body,touching,models,hitbox_mesh,style,camera,input_state),
+				None=>self.update_fly_velocity(body,touching,models,hitbox_mesh,style,camera,input_state),
 			}
 		}
 	}
@@ -729,7 +719,7 @@ struct IntersectModel{
 	transform:PhysicsMeshTransform,
 }

-#[derive(Debug,Clone,Copy,Eq,Hash,PartialEq)]
+#[derive(Debug,Clone,Copy,Hash)]
 pub struct ContactCollision{
 	convex_mesh_id:ConvexMeshId<ContactModelId>,
 	face_id:model_physics::MinkowskiFace,
@@ -738,7 +728,7 @@ pub struct ContactCollision{
 pub struct IntersectCollision{
 	convex_mesh_id:ConvexMeshId<IntersectModelId>,
 }
-#[derive(Debug,Clone,Eq,Hash,PartialEq)]
+#[derive(Debug,Clone,Hash)]
 pub enum Collision{
 	Contact(ContactCollision),
 	Intersect(IntersectCollision),
@@ -815,7 +805,7 @@ impl TouchingState{
 				normal:n,
 			}
 		}).collect();
-		crate::push_solve::push_solve(&contacts,velocity)
+		crate::push_solve::push_solve(&contacts,velocity).0
 	}
 	fn constrain_acceleration(&self,models:&PhysicsModels,hitbox_mesh:&HitboxMesh,acceleration:Planar64Vec3)->Planar64Vec3{
 		let contacts:Vec<_>=self.contacts.iter().map(|(convex_mesh_id,face_id)|{
@@ -826,18 +816,17 @@ impl TouchingState{
 				normal:n,
 			}
 		}).collect();
-		crate::push_solve::push_solve(&contacts,acceleration)
+		crate::push_solve::push_solve(&contacts,acceleration).0
 	}
-	fn predict_collision_end(&self,collector:&mut instruction::InstructionCollector<InternalInstruction,Time>,models:&PhysicsModels,hitbox_mesh:&HitboxMesh,body:&Body,start_time:Time){
+	fn predict_collision_end(&self,collector:&mut instruction::InstructionCollector<InternalInstruction,Time>,models:&PhysicsModels,hitbox_mesh:&HitboxMesh,trajectory:&Trajectory,start_time:Time){
 		// let relative_body=body.relative_to(&Body::ZERO);
-		let relative_body=body;
 		for (convex_mesh_id,face_id) in &self.contacts{
 			//detect face slide off
 			let model_mesh=models.contact_mesh(convex_mesh_id);
 			let minkowski=model_physics::MinkowskiMesh::minkowski_sum(model_mesh,hitbox_mesh.transformed_mesh());
-			collector.collect(minkowski.predict_collision_face_out(&relative_body,start_time..collector.time(),*face_id).map(|(_face,time)|{
+			collector.collect(minkowski.predict_collision_face_out(&trajectory,start_time..collector.time(),*face_id).map(|(_face,time)|{
 				TimedInstruction{
-					time:relative_body.time+time.into(),
+					time:trajectory.time+time.into(),
 					instruction:InternalInstruction::CollisionEnd(
 						Collision::Contact(ContactCollision{face_id:*face_id,convex_mesh_id:*convex_mesh_id}),
 						time
@@ -849,9 +838,9 @@ impl TouchingState{
 			//detect model collision in reverse
 			let model_mesh=models.intersect_mesh(convex_mesh_id);
 			let minkowski=model_physics::MinkowskiMesh::minkowski_sum(model_mesh,hitbox_mesh.transformed_mesh());
-			collector.collect(minkowski.predict_collision_out(&relative_body,start_time..collector.time()).map(|(_face,time)|{
+			collector.collect(minkowski.predict_collision_out(&trajectory,start_time..collector.time()).map(|(_face,time)|{
 				TimedInstruction{
-					time:relative_body.time+time.into(),
+					time:trajectory.time+time.into(),
 					instruction:InternalInstruction::CollisionEnd(
 						Collision::Intersect(IntersectCollision{convex_mesh_id:*convex_mesh_id}),
 						time
@@ -886,7 +875,7 @@ pub struct PhysicsState{
 impl Default for PhysicsState{
 	fn default()->Self{
 		Self{
-			body:Body::new(vec3::int(0,50,0),vec3::int(0,0,0),vec3::int(0,-100,0),Time::ZERO),
+			body:Body::new(vec3::int(0,50,0),vec3::int(0,0,0),Time::ZERO),
 			time:Time::ZERO,
 			style:StyleModifiers::default(),
 			touching:TouchingState::default(),
@@ -910,11 +899,14 @@ impl PhysicsState{
 	pub const fn body(&self)->&Body{
 		&self.body
 	}
-	pub fn camera_body(&self)->Body{
-		Body{
-			position:self.body.position+self.style.camera_offset,
-			..self.body
-		}
+	pub fn camera_trajectory(&self,data:&PhysicsData)->Trajectory{
+		let acceleration=self.acceleration(data);
+		Trajectory::new(
+			self.body.position+self.style.camera_offset,
+			self.body.velocity,
+			acceleration,
+			self.body.time,
+		)
 	}
 	pub const fn camera(&self)->PhysicsCamera{
 		self.camera
@@ -943,8 +935,8 @@ impl PhysicsState{
 	fn set_move_state(&mut self,data:&PhysicsData,move_state:MoveState){
 		self.move_state.set_move_state(move_state,&mut self.body,&self.touching,&data.models,&data.hitbox_mesh,&self.style,&self.camera,&self.input_state);
 	}
-	fn apply_input_and_body(&mut self,data:&PhysicsData){
-		self.move_state.apply_input_and_body(&mut self.body,&self.touching,&data.models,&data.hitbox_mesh,&self.style,&self.camera,&self.input_state);
+	fn acceleration(&self,data:&PhysicsData)->Planar64Vec3{
+		self.move_state.acceleration(&self.touching,&data.models,&data.hitbox_mesh,&self.style,&self.camera,&self.input_state)
 	}
 	//state mutated on collision:
 	//Accelerator
@@ -1191,43 +1183,43 @@ impl<'a> PhysicsContext<'a>{
 	}
 }

-	//this is the one who asks
-	fn next_instruction_internal(state:&PhysicsState,data:&PhysicsData,time_limit:Time)->Option<TimedInstruction<InternalInstruction,Time>>{
-		//JUST POLLING!!! NO MUTATION
-		let mut collector=instruction::InstructionCollector::new(time_limit);
+//this is the one who asks
+fn next_instruction_internal(state:&PhysicsState,data:&PhysicsData,time_limit:Time)->Option<TimedInstruction<InternalInstruction,Time>>{
+	//JUST POLLING!!! NO MUTATION
+	let mut collector=instruction::InstructionCollector::new(time_limit);

-		collector.collect(state.next_move_instruction());
+	collector.collect(state.next_move_instruction());

-		//check for collision ends
-		state.touching.predict_collision_end(&mut collector,&data.models,&data.hitbox_mesh,&state.body,state.time);
-		//check for collision starts
-		let mut aabb=aabb::Aabb::default();
-		state.body.grow_aabb(&mut aabb,state.time,collector.time());
-		aabb.inflate(data.hitbox_mesh.halfsize);
-		//relative to moving platforms
-		//let relative_body=state.body.relative_to(&Body::ZERO);
-		let relative_body=&state.body;
-		data.bvh.sample_aabb(&aabb,&mut |convex_mesh_id|{
-			if state.touching.contains(convex_mesh_id){
-				return;
-			}
-			//no checks are needed because of the time limits.
-			let model_mesh=data.models.mesh(*convex_mesh_id);
-			let minkowski=model_physics::MinkowskiMesh::minkowski_sum(model_mesh,data.hitbox_mesh.transformed_mesh());
-			collector.collect(minkowski.predict_collision_in(relative_body,state.time..collector.time())
-				.map(|(face,dt)|
-					TimedInstruction{
-						time:relative_body.time+dt.into(),
-						instruction:InternalInstruction::CollisionStart(
-							Collision::new(*convex_mesh_id,face),
-							dt
-						)
-					}
-				)
-			);
-		});
-		collector.take()
-	}
+	let trajectory=state.body.with_acceleration(state.acceleration(data));
+	//check for collision ends
+	state.touching.predict_collision_end(&mut collector,&data.models,&data.hitbox_mesh,&trajectory,state.time);
+	//check for collision starts
+	let mut aabb=aabb::Aabb::default();
+	trajectory.grow_aabb(&mut aabb,state.time,collector.time());
+	aabb.inflate(data.hitbox_mesh.halfsize);
+	//relative to moving platforms
+	//let relative_body=state.body.relative_to(&Body::ZERO);
+	data.bvh.sample_aabb(&aabb,&mut |convex_mesh_id|{
+		if state.touching.contains(convex_mesh_id){
+			return;
+		}
+		//no checks are needed because of the time limits.
+		let model_mesh=data.models.mesh(*convex_mesh_id);
+		let minkowski=model_physics::MinkowskiMesh::minkowski_sum(model_mesh,data.hitbox_mesh.transformed_mesh());
+		collector.collect(minkowski.predict_collision_in(&trajectory,state.time..collector.time())
+			.map(|(face,dt)|
+				TimedInstruction{
+					time:trajectory.time+dt.into(),
+					instruction:InternalInstruction::CollisionStart(
+						Collision::new(*convex_mesh_id,face),
+						dt
+					)
+				}
+			)
+		);
+	});
+	collector.take()
+}


 fn contact_normal(
@@ -1277,7 +1269,7 @@ fn recalculate_touching(
 		//no checks are needed because of the time limits.
 		let model_mesh=models.mesh(convex_mesh_id);
 		let minkowski=model_physics::MinkowskiMesh::minkowski_sum(model_mesh,hitbox_mesh.transformed_mesh());
-		if minkowski.is_point_in_mesh(body.position){
+		if minkowski.contains_point(body.position){
 			match convex_mesh_id.model_id{
 				//being inside of contact objects is an invalid physics state
 				//but the physics isn't advanced enough to do anything about it yet
@@ -1335,24 +1327,6 @@ fn set_velocity_cull(body:&mut Body,touching:&mut TouchingState,models:&PhysicsM
 fn set_velocity(body:&mut Body,touching:&TouchingState,models:&PhysicsModels,hitbox_mesh:&HitboxMesh,v:Planar64Vec3){
 	body.velocity=touching.constrain_velocity(models,hitbox_mesh,v);
 }
-#[expect(dead_code)]
-fn set_acceleration_cull(body:&mut Body,touching:&mut TouchingState,models:&PhysicsModels,hitbox_mesh:&HitboxMesh,a:Planar64Vec3)->bool{
-	//This is not correct but is better than what I have
-	let mut culled=false;
-	touching.contacts.retain(|convex_mesh_id,face_id|{
-		let n=contact_normal(models,hitbox_mesh,convex_mesh_id,*face_id);
-		let r=n.dot(a).is_positive();
-		if r{
-			culled=true;
-		}
-		!r
-	});
-	set_acceleration(body,touching,models,hitbox_mesh,a);
-	culled
-}
-fn set_acceleration(body:&mut Body,touching:&TouchingState,models:&PhysicsModels,hitbox_mesh:&HitboxMesh,a:Planar64Vec3){
-	body.acceleration=touching.constrain_acceleration(models,hitbox_mesh,a);
-}

 fn teleport(
 	point:Planar64Vec3,
@@ -1371,7 +1345,6 @@ fn teleport(
 	time:Time,
 ){
 	set_position(point,move_state,body,touching,run,mode_state,mode,models,hitbox_mesh,bvh,style,camera,input_state,time);
-	set_acceleration(body,touching,models,hitbox_mesh,style.gravity);
 }
 enum TeleportToSpawnError{
 	NoModel,
@@ -1634,7 +1607,8 @@ fn collision_start_contact(
 	}
 	//doing enum to set the acceleration when surfing
 	//doing input_and_body to refresh the walk state if you hit a wall while accelerating
-	move_state.apply_enum_and_input_and_body(body,touching,models,hitbox_mesh,style,camera,input_state);
+	move_state.update_walk_target(body,touching,models,hitbox_mesh,style,camera,input_state);
+	move_state.update_fly_velocity(body,touching,models,hitbox_mesh,style,camera,input_state);
 }

 fn collision_start_intersect(
@@ -1669,7 +1643,20 @@ fn collision_start_intersect(
 			},
 			Some(gameplay_modes::Zone::Finish)=>{
 				match run.finish(time){
-					Ok(())=>println!("@@@@ Finished run time={}",run.time(time)),
+					Ok(())=>{
+						let time=run.time(time);
+						let h=time.get()/(Time::ONE_SECOND.get()*60*60);
+						let m=(time.get()/(Time::ONE_SECOND.get()*60)).rem_euclid(60);
+						let s=(time.get()/(Time::ONE_SECOND.get())).rem_euclid(60);
+						let ms=(time.get()/(Time::ONE_MILLISECOND.get())).rem_euclid(1000);
+						let us=(time.get()/(Time::ONE_MICROSECOND.get())).rem_euclid(1000);
+						let ns=(time.get()/(Time::ONE_NANOSECOND.get())).rem_euclid(1000);
+						if h==0{
+							println!("@@@@ Finished run time={m:02}:{s:02}.{ms:03}_{us:03}_{ns:03}");
+						}else{
+							println!("@@@@ Finished run time={h}:{m:02}:{s:02}.{ms:03}_{us:03}_{ns:03}");
+						}
+					},
 					Err(e)=>println!("@@@@ Run Finish error:{e:?}"),
 				}
 			},
@@ -1677,7 +1664,7 @@ fn collision_start_intersect(
 			None=>(),
 		}
 	}
-	move_state.apply_enum_and_body(body,touching,models,hitbox_mesh,style,camera,input_state);
+	move_state.update_fly_velocity(body,touching,models,hitbox_mesh,style,camera,input_state);
 	run_teleport_behaviour(intersect.convex_mesh_id.model_id.into(),attr.general.wormhole.as_ref(),mode,move_state,body,touching,run,mode_state,models,hitbox_mesh,bvh,style,camera,input_state,time);
 }

@@ -1705,10 +1692,11 @@ fn collision_end_contact(
 			move_state.set_move_state(MoveState::Air,body,touching,models,hitbox_mesh,style,camera,input_state);
 		}else{
 			// stopped touching something else while walking
-			move_state.apply_enum_and_input_and_body(body,touching,models,hitbox_mesh,style,camera,input_state);
+			move_state.update_walk_target(body,touching,models,hitbox_mesh,style,camera,input_state);
+			move_state.update_fly_velocity(body,touching,models,hitbox_mesh,style,camera,input_state);
 		},
 		// not walking, but stopped touching something
-		None=>move_state.apply_enum_and_body(body,touching,models,hitbox_mesh,style,camera,input_state),
+		None=>move_state.update_fly_velocity(body,touching,models,hitbox_mesh,style,camera,input_state),
 	}
 }
 fn collision_end_intersect(
@@ -1727,7 +1715,7 @@ fn collision_end_intersect(
 	time:Time,
 ){
 	touching.remove_intersect(convex_mesh_id);
-	move_state.apply_enum_and_body(body,touching,models,hitbox_mesh,style,camera,input_state);
+	move_state.update_fly_velocity(body,touching,models,hitbox_mesh,style,camera,input_state);
 	if let Some(mode)=mode{
 		let zone=mode.get_zone(convex_mesh_id.model_id.into());
 		match zone{
@@ -1743,99 +1731,100 @@ fn collision_end_intersect(
 }
 fn atomic_internal_instruction(state:&mut PhysicsState,data:&PhysicsData,ins:TimedInstruction<InternalInstruction,Time>){
 	state.time=ins.time;
-	let (should_advance_body,goober_time)=match ins.instruction{
+	match ins.instruction{
+		// collisions advance the body precisely
 		InternalInstruction::CollisionStart(_,dt)
-		|InternalInstruction::CollisionEnd(_,dt)=>(true,Some(dt)),
-		InternalInstruction::StrafeTick
-		|InternalInstruction::ReachWalkTargetVelocity=>(true,None),
-	};
-	if should_advance_body{
-		match goober_time{
-			Some(dt)=>state.body.advance_time_ratio_dt(dt),
-			None=>state.body.advance_time(state.time),
-		}
+		|InternalInstruction::CollisionEnd(_,dt)=>{
+			state.body=state.body.with_acceleration(state.acceleration(data)).extrapolated_body_ratio_dt(dt);
+		},
+		// this advances imprecisely
+		InternalInstruction::ReachWalkTargetVelocity=>state.body=state.body.with_acceleration(state.acceleration(data)).extrapolated_body(state.time),
+		// strafe tick decides for itself whether to advance the body.
+		InternalInstruction::StrafeTick=>(),
 	}
-		match ins.instruction{
-			InternalInstruction::CollisionStart(collision,_)=>{
-				let mode=data.modes.get_mode(state.mode_state.get_mode_id());
-				match collision{
-					Collision::Contact(contact)=>collision_start_contact(
-						&mut state.move_state,&mut state.body,&mut state.mode_state,&mut state.touching,&mut state.run,
-						mode,
-						&data.models,&data.hitbox_mesh,&data.bvh,&state.style,&state.camera,&state.input_state,
-						data.models.contact_attr(contact.convex_mesh_id.model_id),
-						contact,
-						state.time,
-					),
-					Collision::Intersect(intersect)=>collision_start_intersect(
-						&mut state.move_state,&mut state.body,&mut state.mode_state,&mut state.touching,
-						mode,
-						&mut state.run,&data.models,&data.hitbox_mesh,&data.bvh,&state.style,&state.camera,&state.input_state,
-						data.models.intersect_attr(intersect.convex_mesh_id.model_id),
-						intersect,
-						state.time,
-					),
-				}
-			},
-			InternalInstruction::CollisionEnd(collision,_)=>match collision{
-				Collision::Contact(contact)=>collision_end_contact(
-					&mut state.move_state,&mut state.body,&mut state.touching,&data.models,&data.hitbox_mesh,&state.style,&state.camera,&state.input_state,
+	match ins.instruction{
+		InternalInstruction::CollisionStart(collision,_)=>{
+			let mode=data.modes.get_mode(state.mode_state.get_mode_id());
+			match collision{
+				Collision::Contact(contact)=>collision_start_contact(
+					&mut state.move_state,&mut state.body,&mut state.mode_state,&mut state.touching,&mut state.run,
+					mode,
+					&data.models,&data.hitbox_mesh,&data.bvh,&state.style,&state.camera,&state.input_state,
 					data.models.contact_attr(contact.convex_mesh_id.model_id),
-					&contact.convex_mesh_id
+					contact,
+					state.time,
 				),
-				Collision::Intersect(intersect)=>collision_end_intersect(
-					&mut state.move_state,&mut state.body,&mut state.touching,&data.models,&data.hitbox_mesh,&state.style,&state.camera,&state.input_state,
-					data.modes.get_mode(state.mode_state.get_mode_id()),
-					&mut state.run,
+				Collision::Intersect(intersect)=>collision_start_intersect(
+					&mut state.move_state,&mut state.body,&mut state.mode_state,&mut state.touching,
+					mode,
+					&mut state.run,&data.models,&data.hitbox_mesh,&data.bvh,&state.style,&state.camera,&state.input_state,
 					data.models.intersect_attr(intersect.convex_mesh_id.model_id),
-					&intersect.convex_mesh_id,
-					state.time
+					intersect,
+					state.time,
 				),
-			},
-			InternalInstruction::StrafeTick=>{
-				//TODO make this less huge
-				if let Some(strafe_settings)=&state.style.strafe{
-					let controls=state.input_state.controls;
-					if strafe_settings.activates(controls){
-						let masked_controls=strafe_settings.mask(controls);
-						let control_dir=state.style.get_control_dir(masked_controls);
-						if control_dir!=vec3::zero(){
-							let camera_mat=state.camera.simulate_move_rotation_y(state.input_state.lerp_delta(state.time).x);
-							if let Some(ticked_velocity)=strafe_settings.tick_velocity(state.body.velocity,(camera_mat*control_dir).with_length(Planar64::ONE).divide().wrap_1()){
-								//this is wrong but will work ig
-								//need to note which push planes activate in push solve and keep those
-								state.cull_velocity(data,ticked_velocity);
-							}
+			}
+		},
+		InternalInstruction::CollisionEnd(collision,_)=>match collision{
+			Collision::Contact(contact)=>collision_end_contact(
+				&mut state.move_state,&mut state.body,&mut state.touching,&data.models,&data.hitbox_mesh,&state.style,&state.camera,&state.input_state,
+				data.models.contact_attr(contact.convex_mesh_id.model_id),
+				&contact.convex_mesh_id
+			),
+			Collision::Intersect(intersect)=>collision_end_intersect(
+				&mut state.move_state,&mut state.body,&mut state.touching,&data.models,&data.hitbox_mesh,&state.style,&state.camera,&state.input_state,
+				data.modes.get_mode(state.mode_state.get_mode_id()),
+				&mut state.run,
+				data.models.intersect_attr(intersect.convex_mesh_id.model_id),
+				&intersect.convex_mesh_id,
+				state.time
+			),
+		},
+		InternalInstruction::StrafeTick=>{
+			//TODO make this less huge
+			if let Some(strafe_settings)=&state.style.strafe{
+				let controls=state.input_state.controls;
+				if strafe_settings.activates(controls){
+					let masked_controls=strafe_settings.mask(controls);
+					let control_dir=state.style.get_control_dir(masked_controls);
+					if control_dir!=vec3::zero(){
+						// manually advance time
+						let extrapolated_body=state.body.with_acceleration(state.acceleration(data)).extrapolated_body(state.time);
+						let camera_mat=state.camera.simulate_move_rotation_y(state.input_state.lerp_delta(state.time).x);
+						if let Some(ticked_velocity)=strafe_settings.tick_velocity(extrapolated_body.velocity,(camera_mat*control_dir).with_length(Planar64::ONE).divide().wrap_1()){
+							state.body=extrapolated_body;
+							//this is wrong but will work ig
+							//need to note which push planes activate in push solve and keep those
+							state.cull_velocity(data,ticked_velocity);
 						}
 					}
 				}
 			}
-			InternalInstruction::ReachWalkTargetVelocity=>{
-				match &mut state.move_state{
-					MoveState::Air
-					|MoveState::Water
-					|MoveState::Fly
-					=>println!("ReachWalkTargetVelocity fired for non-walking MoveState"),
-					MoveState::Walk(walk_state)|MoveState::Ladder(walk_state)=>{
-						//velocity is already handled by advance_time
-						//we know that the acceleration is precisely zero because the walk target is known to be reachable
-						//which means that gravity can be fully cancelled
-						//ignore moving platforms for now
-						let target=core::mem::replace(&mut walk_state.target,TransientAcceleration::Reached);
-						set_acceleration(&mut state.body,&state.touching,&data.models,&data.hitbox_mesh,vec3::zero());
-						// check what the target was to see if it was invalid
-						match target{
-							//you are not supposed to reach a walk target which is already reached!
-							TransientAcceleration::Reached=>println!("Invalid walk target: Reached"),
-							TransientAcceleration::Reachable{..}=>(),
-							//you are not supposed to reach an unreachable walk target!
-							TransientAcceleration::Unreachable{..}=>println!("Invalid walk target: Unreachable"),
-						}
+		}
+		InternalInstruction::ReachWalkTargetVelocity=>{
+			match &mut state.move_state{
+				MoveState::Air
+				|MoveState::Water
+				|MoveState::Fly
+				=>println!("ReachWalkTargetVelocity fired for non-walking MoveState"),
+				MoveState::Walk(walk_state)|MoveState::Ladder(walk_state)=>{
+					//velocity is already handled by extrapolated_body
+					//we know that the acceleration is precisely zero because the walk target is known to be reachable
+					//which means that gravity can be fully cancelled
+					//ignore moving platforms for now
+					let target=core::mem::replace(&mut walk_state.target,TransientAcceleration::Reached);
+					// check what the target was to see if it was invalid
+					match target{
+						//you are not supposed to reach a walk target which is already reached!
+						TransientAcceleration::Reached=>println!("Invalid walk target: Reached"),
+						TransientAcceleration::Reachable{..}=>(),
+						//you are not supposed to reach an unreachable walk target!
+						TransientAcceleration::Unreachable{..}=>println!("Invalid walk target: Unreachable"),
 					}
 				}
-			},
-		}
+			}
+		},
 	}
+}

 fn atomic_input_instruction(state:&mut PhysicsState,data:&PhysicsData,ins:TimedInstruction<Instruction,Time>){
 	state.time=ins.time;
@@ -1861,7 +1850,7 @@ fn atomic_input_instruction(state:&mut PhysicsState,data:&PhysicsData,ins:TimedI
 		Instruction::Misc(MiscInstruction::PracticeFly)=>true,
 	};
 	if should_advance_body{
-		state.body.advance_time(state.time);
+		state.body=state.body.with_acceleration(state.acceleration(data)).extrapolated_body(state.time);
 	}

 	let mut b_refresh_walk_target=true;
@@ -1897,6 +1886,9 @@ fn atomic_input_instruction(state:&mut PhysicsState,data:&PhysicsData,ins:TimedI
 			state.input_state.set_control(Controls::Zoom,s);
 			b_refresh_walk_target=false;
 		},
+		Instruction::SetControl(SetControlInstruction::SetSprint(s))=>{
+			state.input_state.set_control(Controls::Sprint,s);
+		},
 		Instruction::Mode(ModeInstruction::Reset)=>{
 			//totally reset physics state
 			state.reset_to_default();
@@ -1956,7 +1948,8 @@ fn atomic_input_instruction(state:&mut PhysicsState,data:&PhysicsData,ins:TimedI
 		},
 	}
 	if b_refresh_walk_target{
-		state.apply_input_and_body(data);
+		state.move_state.update_walk_target(&mut state.body,&state.touching,&data.models,&data.hitbox_mesh,&state.style,&state.camera,&state.input_state);
+		state.move_state.update_fly_velocity(&mut state.body,&state.touching,&data.models,&data.hitbox_mesh,&state.style,&state.camera,&state.input_state);
 		state.cull_velocity(data,state.body.velocity);
 		//also check if accelerating away from surface
 	}
@@ -1966,16 +1959,16 @@ fn atomic_input_instruction(state:&mut PhysicsState,data:&PhysicsData,ins:TimedI
 mod test{
 	use strafesnet_common::integer::{vec3::{self,int as int3},mat3};
 	use super::*;
-	fn test_collision_axis_aligned(relative_body:Body,expected_collision_time:Option<Time>){
+	fn test_collision_axis_aligned(relative_body:Trajectory,expected_collision_time:Option<Time>){
 		let h0=HitboxMesh::new(PhysicsMesh::unit_cube(),integer::Planar64Affine3::new(mat3::from_diagonal(int3(5,1,5)>>1),vec3::zero()));
 		let h1=StyleModifiers::roblox_bhop().calculate_mesh();
 		let hitbox_mesh=h1.transformed_mesh();
 		let platform_mesh=h0.transformed_mesh();
 		let minkowski=model_physics::MinkowskiMesh::minkowski_sum(platform_mesh,hitbox_mesh);
-		let collision=minkowski.predict_collision_in(&relative_body,Time::ZERO..Time::from_secs(10));
+		let collision=minkowski.predict_collision_in(&relative_body,..);
 		assert_eq!(collision.map(|tup|relative_body.time+tup.1.into()),expected_collision_time,"Incorrect time of collision");
 	}
-	fn test_collision_rotated(relative_body:Body,expected_collision_time:Option<Time>){
+	fn test_collision_rotated(relative_body:Trajectory,expected_collision_time:Option<Time>){
 		let h0=HitboxMesh::new(PhysicsMesh::unit_cube(),
 			integer::Planar64Affine3::new(
 				Planar64Mat3::from_cols([
@@ -1990,16 +1983,16 @@ mod test{
 		let hitbox_mesh=h1.transformed_mesh();
 		let platform_mesh=h0.transformed_mesh();
 		let minkowski=model_physics::MinkowskiMesh::minkowski_sum(platform_mesh,hitbox_mesh);
-		let collision=minkowski.predict_collision_in(&relative_body,Time::ZERO..Time::from_secs(10));
+		let collision=minkowski.predict_collision_in(&relative_body,..);
 		assert_eq!(collision.map(|tup|relative_body.time+tup.1.into()),expected_collision_time,"Incorrect time of collision");
 	}
-	fn test_collision(relative_body:Body,expected_collision_time:Option<Time>){
+	fn test_collision(relative_body:Trajectory,expected_collision_time:Option<Time>){
 		test_collision_axis_aligned(relative_body,expected_collision_time);
 		test_collision_rotated(relative_body,expected_collision_time);
 	}
 	#[test]
 	fn test_collision_degenerate_straight_down(){
-		test_collision(Body::new(
+		test_collision(Trajectory::new(
 			int3(0,5,0),
 			int3(0,-1,0),
 			vec3::zero(),
@@ -2008,7 +2001,7 @@ mod test{
 	}
 	#[test]
 	fn test_collision_small_mv(){
-		test_collision(Body::new(
+		test_collision(Trajectory::new(
 			int3(0,5,0),
 			int3(0,-1,0)+(vec3::X>>32),
 			vec3::zero(),
@@ -2017,7 +2010,7 @@ mod test{
 	}
 	#[test]
 	fn test_collision_degenerate_east(){
-		test_collision(Body::new(
+		test_collision(Trajectory::new(
 			int3(3,5,0),
 			int3(0,-1,0),
 			vec3::zero(),
@@ -2026,7 +2019,7 @@ mod test{
 	}
 	#[test]
 	fn test_collision_degenerate_south(){
-		test_collision(Body::new(
+		test_collision(Trajectory::new(
 			int3(0,5,3),
 			int3(0,-1,0),
 			vec3::zero(),
@@ -2035,7 +2028,7 @@ mod test{
 	}
 	#[test]
 	fn test_collision_degenerate_west(){
-		test_collision(Body::new(
+		test_collision(Trajectory::new(
 			int3(-3,5,0),
 			int3(0,-1,0),
 			vec3::zero(),
@@ -2044,7 +2037,7 @@ mod test{
 	}
 	#[test]
 	fn test_collision_degenerate_north(){
-		test_collision(Body::new(
+		test_collision(Trajectory::new(
 			int3(0,5,-3),
 			int3(0,-1,0),
 			vec3::zero(),
@@ -2053,115 +2046,115 @@ mod test{
 	}
 	#[test]
 	fn test_collision_parabola_edge_east_from_west(){
-		test_collision(Body::new(
+		test_collision(Trajectory::new(
 			int3(3,3,0),
 			int3(100,-1,0),
 			int3(0,-1,0),
 			Time::ZERO
-		).relative_to(&Body::ZERO).body(Time::from_secs(-1)),Some(Time::from_secs(0)));
+		).relative_to(&Trajectory::ZERO,Time::from_secs(-1)),Some(Time::from_secs(0)));
 	}
 	#[test]
 	fn test_collision_parabola_edge_south_from_north(){
-		test_collision(Body::new(
+		test_collision(Trajectory::new(
 			int3(0,3,3),
 			int3(0,-1,100),
 			int3(0,-1,0),
 			Time::ZERO
-		).relative_to(&Body::ZERO).body(Time::from_secs(-1)),Some(Time::from_secs(0)));
+		).relative_to(&Trajectory::ZERO,Time::from_secs(-1)),Some(Time::from_secs(0)));
 	}
 	#[test]
 	fn test_collision_parabola_edge_west_from_east(){
-		test_collision(Body::new(
+		test_collision(Trajectory::new(
 			int3(-3,3,0),
 			int3(-100,-1,0),
 			int3(0,-1,0),
 			Time::ZERO
-		).relative_to(&Body::ZERO).body(Time::from_secs(-1)),Some(Time::from_secs(0)));
+		).relative_to(&Trajectory::ZERO,Time::from_secs(-1)),Some(Time::from_secs(0)));
 	}
 	#[test]
 	fn test_collision_parabola_edge_north_from_south(){
-		test_collision(Body::new(
+		test_collision(Trajectory::new(
 			int3(0,3,-3),
 			int3(0,-1,-100),
 			int3(0,-1,0),
 			Time::ZERO
-		).relative_to(&Body::ZERO).body(Time::from_secs(-1)),Some(Time::from_secs(0)));
+		).relative_to(&Trajectory::ZERO,Time::from_secs(-1)),Some(Time::from_secs(0)));
 	}
 	#[test]
 	fn test_collision_parabola_edge_north_from_ne(){
-		test_collision(Body::new(
+		test_collision(Trajectory::new(
 			int3(0,6,-7)>>1,
 			int3(-10,-1,1),
 			int3(0,-1,0),
 			Time::ZERO
-		).relative_to(&Body::ZERO).body(Time::from_secs(-1)),Some(Time::from_secs(0)));
+		).relative_to(&Trajectory::ZERO,Time::from_secs(-1)),Some(Time::from_secs(0)));
 	}
 	#[test]
 	fn test_collision_parabola_edge_north_from_nw(){
-		test_collision(Body::new(
+		test_collision(Trajectory::new(
 			int3(0,6,-7)>>1,
 			int3(10,-1,1),
 			int3(0,-1,0),
 			Time::ZERO
-		).relative_to(&Body::ZERO).body(Time::from_secs(-1)),Some(Time::from_secs(0)));
+		).relative_to(&Trajectory::ZERO,Time::from_secs(-1)),Some(Time::from_secs(0)));
 	}
 	#[test]
 	fn test_collision_parabola_edge_east_from_se(){
-		test_collision(Body::new(
+		test_collision(Trajectory::new(
 			int3(7,6,0)>>1,
 			int3(-1,-1,-10),
 			int3(0,-1,0),
 			Time::ZERO
-		).relative_to(&Body::ZERO).body(Time::from_secs(-1)),Some(Time::from_secs(0)));
+		).relative_to(&Trajectory::ZERO,Time::from_secs(-1)),Some(Time::from_secs(0)));
 	}
 	#[test]
 	fn test_collision_parabola_edge_east_from_ne(){
-		test_collision(Body::new(
+		test_collision(Trajectory::new(
 			int3(7,6,0)>>1,
 			int3(-1,-1,10),
 			int3(0,-1,0),
 			Time::ZERO
-		).relative_to(&Body::ZERO).body(Time::from_secs(-1)),Some(Time::from_secs(0)));
+		).relative_to(&Trajectory::ZERO,Time::from_secs(-1)),Some(Time::from_secs(0)));
 	}
 	#[test]
 	fn test_collision_parabola_edge_south_from_se(){
-		test_collision(Body::new(
+		test_collision(Trajectory::new(
 			int3(0,6,7)>>1,
 			int3(-10,-1,-1),
 			int3(0,-1,0),
 			Time::ZERO
-		).relative_to(&Body::ZERO).body(Time::from_secs(-1)),Some(Time::from_secs(0)));
+		).relative_to(&Trajectory::ZERO,Time::from_secs(-1)),Some(Time::from_secs(0)));
 	}
 	#[test]
 	fn test_collision_parabola_edge_south_from_sw(){
-		test_collision(Body::new(
+		test_collision(Trajectory::new(
 			int3(0,6,7)>>1,
 			int3(10,-1,-1),
 			int3(0,-1,0),
 			Time::ZERO
-		).relative_to(&Body::ZERO).body(Time::from_secs(-1)),Some(Time::from_secs(0)));
+		).relative_to(&Trajectory::ZERO,Time::from_secs(-1)),Some(Time::from_secs(0)));
 	}
 	#[test]
 	fn test_collision_parabola_edge_west_from_se(){
-		test_collision(Body::new(
+		test_collision(Trajectory::new(
 			int3(-7,6,0)>>1,
 			int3(1,-1,-10),
 			int3(0,-1,0),
 			Time::ZERO
-		).relative_to(&Body::ZERO).body(Time::from_secs(-1)),Some(Time::from_secs(0)));
+		).relative_to(&Trajectory::ZERO,Time::from_secs(-1)),Some(Time::from_secs(0)));
 	}
 	#[test]
 	fn test_collision_parabola_edge_west_from_ne(){
-		test_collision(Body::new(
+		test_collision(Trajectory::new(
 			int3(-7,6,0)>>1,
 			int3(1,-1,10),
 			int3(0,-1,0),
 			Time::ZERO
-		).relative_to(&Body::ZERO).body(Time::from_secs(-1)),Some(Time::from_secs(0)));
+		).relative_to(&Trajectory::ZERO,Time::from_secs(-1)),Some(Time::from_secs(0)));
 	}
 	#[test]
 	fn test_collision_oblique(){
-		test_collision(Body::new(
+		test_collision(Trajectory::new(
 			int3(0,5,0),
 			int3(1,-64,2)>>6,// /64
 			vec3::zero(),
@@ -2170,7 +2163,7 @@ mod test{
 	}
 	#[test]
 	fn zoom_hit_nothing(){
-		test_collision(Body::new(
+		test_collision(Trajectory::new(
 			int3(0,10,0),
 			int3(1,0,0),
 			int3(0,1,0),
@@ -2179,7 +2172,7 @@ mod test{
 	}
 	#[test]
 	fn already_inside_hit_nothing(){
-		test_collision(Body::new(
+		test_collision(Trajectory::new(
 			vec3::zero(),
 			int3(1,0,0),
 			int3(0,1,0),
@@ -2189,7 +2182,7 @@ mod test{
 	// overlap edges by 1 epsilon
 	#[test]
 	fn almost_miss_north(){
-		test_collision_axis_aligned(Body::new(
+		test_collision_axis_aligned(Trajectory::new(
 			(int3(0,10,-7)>>1)+vec3::raw_xyz(0,0,1),
 			int3(0,-1,0),
 			vec3::zero(),
@@ -2198,7 +2191,7 @@ mod test{
 	}
 	#[test]
 	fn almost_miss_east(){
-		test_collision_axis_aligned(Body::new(
+		test_collision_axis_aligned(Trajectory::new(
 			(int3(7,10,0)>>1)+vec3::raw_xyz(-1,0,0),
 			int3(0,-1,0),
 			vec3::zero(),
@@ -2207,7 +2200,7 @@ mod test{
 	}
 	#[test]
 	fn almost_miss_south(){
-		test_collision_axis_aligned(Body::new(
+		test_collision_axis_aligned(Trajectory::new(
 			(int3(0,10,7)>>1)+vec3::raw_xyz(0,0,-1),
 			int3(0,-1,0),
 			vec3::zero(),
@@ -2216,7 +2209,7 @@ mod test{
 	}
 	#[test]
 	fn almost_miss_west(){
-		test_collision_axis_aligned(Body::new(
+		test_collision_axis_aligned(Trajectory::new(
 			(int3(-7,10,0)>>1)+vec3::raw_xyz(1,0,0),
 			int3(0,-1,0),
 			vec3::zero(),
@@ -2226,7 +2219,7 @@ mod test{
 	// exactly miss edges
 	#[test]
 	fn exact_miss_north(){
-		test_collision_axis_aligned(Body::new(
+		test_collision_axis_aligned(Trajectory::new(
 			int3(0,10,-7)>>1,
 			int3(0,-1,0),
 			vec3::zero(),
@@ -2235,7 +2228,7 @@ mod test{
 	}
 	#[test]
 	fn exact_miss_east(){
-		test_collision_axis_aligned(Body::new(
+		test_collision_axis_aligned(Trajectory::new(
 			int3(7,10,0)>>1,
 			int3(0,-1,0),
 			vec3::zero(),
@@ -2244,7 +2237,7 @@ mod test{
 	}
 	#[test]
 	fn exact_miss_south(){
-		test_collision_axis_aligned(Body::new(
+		test_collision_axis_aligned(Trajectory::new(
 			int3(0,10,7)>>1,
 			int3(0,-1,0),
 			vec3::zero(),
@@ -2253,7 +2246,7 @@ mod test{
 	}
 	#[test]
 	fn exact_miss_west(){
-		test_collision_axis_aligned(Body::new(
+		test_collision_axis_aligned(Trajectory::new(
 			int3(-7,10,0)>>1,
 			int3(0,-1,0),
 			vec3::zero(),
@@ -2263,7 +2256,7 @@ mod test{
 	// miss edges by 1 epsilon
 	#[test]
 	fn narrow_miss_north(){
-		test_collision_axis_aligned(Body::new(
+		test_collision_axis_aligned(Trajectory::new(
 			(int3(0,10,-7)>>1)-vec3::raw_xyz(0,0,1),
 			int3(0,-1,0),
 			vec3::zero(),
@@ -2272,7 +2265,7 @@ mod test{
 	}
 	#[test]
 	fn narrow_miss_east(){
-		test_collision_axis_aligned(Body::new(
+		test_collision_axis_aligned(Trajectory::new(
 			(int3(7,10,0)>>1)-vec3::raw_xyz(-1,0,0),
 			int3(0,-1,0),
 			vec3::zero(),
@@ -2281,7 +2274,7 @@ mod test{
 	}
 	#[test]
 	fn narrow_miss_south(){
-		test_collision_axis_aligned(Body::new(
+		test_collision_axis_aligned(Trajectory::new(
 			(int3(0,10,7)>>1)-vec3::raw_xyz(0,0,-1),
 			int3(0,-1,0),
 			vec3::zero(),
@@ -2290,7 +2283,7 @@ mod test{
 	}
 	#[test]
 	fn narrow_miss_west(){
-		test_collision_axis_aligned(Body::new(
+		test_collision_axis_aligned(Trajectory::new(
 			(int3(-7,10,0)>>1)-vec3::raw_xyz(1,0,0),
 			int3(0,-1,0),
 			vec3::zero(),
--- a/engine/physics/src/push_solve.rs
+++ b/engine/physics/src/push_solve.rs
@@ -15,6 +15,7 @@ type Conts<'a>=arrayvec::ArrayVec<&'a Contact,4>;
 const RATIO_ZERO:Ratio<Fixed<1,32>,Fixed<1,32>>=Ratio::new(Fixed::ZERO,Fixed::EPSILON);

 /// Information about a contact restriction
+#[derive(Debug,PartialEq)]
 pub struct Contact{
 	pub position:Planar64Vec3,
 	pub velocity:Planar64Vec3,
@@ -281,16 +282,16 @@ fn get_first_touch<'a>(contacts:&'a [Contact],ray:&Ray,conts:&Conts)->Option<(Ra
 		.min_by_key(|&(t,_)|t)
 }

-pub fn push_solve(contacts:&[Contact],point:Planar64Vec3)->Planar64Vec3{
+pub fn push_solve(contacts:&[Contact],point:Planar64Vec3)->(Planar64Vec3,Conts<'_>){
 	let (mut ray,mut conts)=get_best_push_ray_and_conts_0(point);
 	loop{
 		let (next_t,next_cont)=match get_first_touch(contacts,&ray,&conts){
 			Some((t,cont))=>(t,cont),
-			None=>return ray.origin,
+			None=>return (ray.origin,conts),
 		};

 		if RATIO_ZERO.le_ratio(next_t){
-			return ray.origin;
+			return (ray.origin,conts);
 		}

 		//push_front
@@ -306,7 +307,7 @@ pub fn push_solve(contacts:&[Contact],point:Planar64Vec3)->Planar64Vec3{
 		let meet_point=ray.extrapolate(next_t);
 		match get_best_push_ray_and_conts(meet_point,conts.as_slice()){
 			Some((new_ray,new_conts))=>(ray,conts)=(new_ray,new_conts),
-			None=>return meet_point,
+			None=>return (meet_point,conts),
 		}
 	}
 }
@@ -323,9 +324,8 @@ mod tests{
 				normal:vec3::Y,
 			}
 		];
-		assert_eq!(
-			vec3::zero(),
-			push_solve(&contacts,vec3::NEG_Y)
-		);
+		let (point,conts)=push_solve(&contacts,vec3::NEG_Y);
+		assert_eq!(point,vec3::zero());
+		assert_eq!(conts.as_slice(),[&contacts[0]].as_slice());
 	}
 }
--- a/engine/session/src/session.rs
+++ b/engine/session/src/session.rs
@@ -52,13 +52,12 @@ pub enum SessionControlInstruction{
 pub enum SessionPlaybackInstruction{
 	SkipForward,
 	SkipBack,
-	TogglePaused,
 	DecreaseTimescale,
 	IncreaseTimescale,
 }

 pub struct FrameState{
-	pub body:physics::Body,
+	pub trajectory:physics::Trajectory,
 	pub camera:physics::PhysicsCamera,
 	pub time:PhysicsTime,
 }
@@ -77,9 +76,9 @@ impl Simulation{
 			physics,
 		}
 	}
-	pub fn get_frame_state(&self,time:SessionTime)->FrameState{
+	pub fn get_frame_state(&self,time:SessionTime,data:&PhysicsData)->FrameState{
 		FrameState{
-			body:self.physics.camera_body(),
+			trajectory:self.physics.camera_trajectory(data),
 			camera:self.physics.camera(),
 			time:self.timer.time(time),
 		}
@@ -188,9 +187,9 @@ impl Session{
 	}
 	pub fn get_frame_state(&self,time:SessionTime)->Option<FrameState>{
 		match &self.view_state{
-			ViewState::Play=>Some(self.simulation.get_frame_state(time)),
+			ViewState::Play=>Some(self.simulation.get_frame_state(time,&self.geometry_shared)),
 			ViewState::Replay(bot_id)=>self.replays.get(bot_id).map(|replay|
-				replay.simulation.get_frame_state(time)
+				replay.simulation.get_frame_state(time,&self.geometry_shared)
 			),
 		}
 	}
@@ -239,12 +238,16 @@ impl InstructionConsumer<Instruction<'_>> for Session{
 				run_mouse_interpolator_instruction!(MouseInterpolatorInstruction::Mode(ModeInstruction::Reset));
 				run_mouse_interpolator_instruction!(MouseInterpolatorInstruction::Misc(MiscInstruction::SetSensitivity(self.user_settings().calculate_sensitivity())));
 				run_mouse_interpolator_instruction!(MouseInterpolatorInstruction::Mode(ModeInstruction::Restart(mode_id)));
+				// TODO: think about this harder.  This works around a bug where you fall infinitely when you reset.
+				self.simulation.timer.set_time(ins.time,PhysicsTime::ZERO);
 			},
 			Instruction::Input(SessionInputInstruction::Mode(ImplicitModeInstruction::ResetAndSpawn(mode_id,spawn_id)))=>{
 				self.clear_recording();
 				run_mouse_interpolator_instruction!(MouseInterpolatorInstruction::Mode(ModeInstruction::Reset));
 				run_mouse_interpolator_instruction!(MouseInterpolatorInstruction::Misc(MiscInstruction::SetSensitivity(self.user_settings().calculate_sensitivity())));
 				run_mouse_interpolator_instruction!(MouseInterpolatorInstruction::Mode(ModeInstruction::Spawn(mode_id,spawn_id)));
+				// TODO: think about this harder.  This works around a bug where you fall infinitely when you reset.
+				self.simulation.timer.set_time(ins.time,PhysicsTime::ZERO);
 			},
 			Instruction::Input(SessionInputInstruction::Misc(misc_instruction))=>{
 				run_mouse_interpolator_instruction!(MouseInterpolatorInstruction::Misc(misc_instruction));
@@ -253,7 +256,14 @@ impl InstructionConsumer<Instruction<'_>> for Session{
 				// don't flush the buffered instructions in the mouse interpolator
 				// until the mouse is confirmed to be not moving at a later time
 				// what if they pause for 5ms lmao
-				_=self.simulation.timer.set_paused(ins.time,paused);
+				match &self.view_state{
+					ViewState::Play=>{
+						_=self.simulation.timer.set_paused(ins.time,paused);
+					},
+					ViewState::Replay(bot_id)=>if let Some(replay)=self.replays.get_mut(bot_id){
+						_=replay.simulation.timer.set_paused(ins.time,paused);
+					},
+				}
 			},
 			Instruction::Control(SessionControlInstruction::CopyRecordingIntoReplayAndSpectate)=> if let ViewState::Play=self.view_state{
 				// Bind: B
@@ -374,14 +384,6 @@ impl InstructionConsumer<Instruction<'_>> for Session{
 					},
 				}
 			},
-			Instruction::Playback(SessionPlaybackInstruction::TogglePaused)=>{
-				match &self.view_state{
-					ViewState::Play=>(),
-					ViewState::Replay(bot_id)=>if let Some(replay)=self.replays.get_mut(bot_id){
-						_=replay.simulation.timer.set_paused(ins.time,!replay.simulation.timer.is_paused());
-					},
-				}
-			}
 			Instruction::ChangeMap(complete_map)=>{
 				self.clear_recording();
 				self.change_map(complete_map);
--- a/integration-testing/src/main.rs
+++ b/integration-testing/src/main.rs
@@ -71,16 +71,16 @@ fn segment_determinism(bot:strafesnet_snf::bot::Segment,physics_data:&PhysicsDat
 	for (i,ins) in bot.instructions.into_iter().enumerate(){
 		let state_deterministic=physics_deterministic.clone();
 		let state_filtered=physics_filtered.clone();
-		PhysicsContext::run_input_instruction(&mut physics_deterministic,&physics_data,ins.clone());
+		PhysicsContext::run_input_instruction(&mut physics_deterministic,physics_data,ins.clone());
 		match ins{
 			strafesnet_common::instruction::TimedInstruction{instruction:strafesnet_common::physics::Instruction::Idle,..}=>(),
 			other=>{
 				non_idle_count+=1;
 				// run
-				PhysicsContext::run_input_instruction(&mut physics_filtered,&physics_data,other.clone());
+				PhysicsContext::run_input_instruction(&mut physics_filtered,physics_data,other.clone());
 				// check if position matches
-				let b0=physics_deterministic.camera_body();
-				let b1=physics_filtered.camera_body();
+				let b0=physics_deterministic.camera_trajectory(physics_data);
+				let b1=physics_filtered.camera_trajectory(physics_data);
 				if b0.position!=b1.position{
 					let nanoseconds=start.elapsed().as_nanos() as u64;
 					println!("desync at instruction #{}",i);
--- a/integration-testing/src/test_scenes.rs
+++ b/integration-testing/src/test_scenes.rs
@@ -73,7 +73,6 @@ fn simultaneous_collision(){
 	let body=strafesnet_physics::physics::Body::new(
 		(vec3::int(5+2,0,0)>>1)+vec3::int(1,1,0),
 		vec3::int(-1,-1,0),
-		vec3::int(0,0,0),
 		Time::ZERO,
 	);
 	let mut physics=PhysicsState::new_with_body(body);
@@ -88,7 +87,6 @@ fn simultaneous_collision(){
 	let body=physics.body();
 	assert_eq!(body.position,vec3::int(5,0,0));
 	assert_eq!(body.velocity,vec3::int(0,0,0));
-	assert_eq!(body.acceleration,vec3::int(0,0,0));
 	assert_eq!(body.time,Time::from_secs(1));
 }
 #[test]
@@ -97,7 +95,6 @@ fn bug_3(){
 	let body=strafesnet_physics::physics::Body::new(
 		(vec3::int(5+2,0,0)>>1)+vec3::int(1,2,0),
 		vec3::int(-1,-1,0),
-		vec3::int(0,0,0),
 		Time::ZERO,
 	);
 	let mut physics=PhysicsState::new_with_body(body);
@@ -112,6 +109,5 @@ fn bug_3(){
 	let body=physics.body();
 	assert_eq!(body.position,vec3::int(5+2,0,0)>>1);
 	assert_eq!(body.velocity,vec3::int(0,0,0));
-	assert_eq!(body.acceleration,vec3::int(0,0,0));
 	assert_eq!(body.time,Time::from_secs(2));
 }
--- a/integration-testing/src/tests.rs
+++ b/integration-testing/src/tests.rs
@@ -22,7 +22,6 @@ fn physics_bug_2()->Result<(),ReplayError>{
 	let body=strafesnet_physics::physics::Body::new(
 		vec3::raw_xyz(555690659654,1490485868773,1277783839382),
 		vec3::int(0,0,0),
-		vec3::int(0,-100,0),
 		Time::ZERO,
 	);
 	let mut physics=PhysicsState::new_with_body(body);
@@ -60,9 +59,12 @@ fn physics_bug_3()->Result<(),ReplayError>{
 		// vec3::raw_xyz(0,-96915585363,1265),
 		// vec3::raw_xyz(0,-429496729600,0),
 		// corner setup before wall hits
-		vec3::raw_xyz(-1392580080675,3325402529458,-2444727738679),
-		vec3::raw_xyz(-30259028820,-22950929553,-71141663007),
-		vec3::raw_xyz(0,-429496729600,0),
+		// vec3::raw_xyz(-1392580080675,3325402529458,-2444727738679),
+		// vec3::raw_xyz(-30259028820,-22950929553,-71141663007),
+		// vec3::raw_xyz(0,-429496729600,0),
+		// Actual bug 3 repro
+		vec3::raw_xyz(-2505538624455,3357963283914,557275711118),
+		vec3::raw_xyz(204188283920,-282280474198,166172785440),
 		Time::ZERO,
 	);
 	let mut physics=PhysicsState::new_with_body(body);
--- a/lib/common/src/physics.rs
+++ b/lib/common/src/physics.rs
@@ -36,6 +36,7 @@ pub enum SetControlInstruction{
 	SetMoveForward(bool),
 	SetJump(bool),
 	SetZoom(bool),
+	SetSprint(bool),
 }
 #[derive(Clone,Debug)]
 pub enum ModeInstruction{
--- a/lib/dag/Cargo.toml
+++ b/lib/dag/Cargo.toml
@@ -0,0 +1,9 @@
+[package]
+name = "dag"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]
+
+[lints]
+workspace = true
--- a/lib/dag/src/lib.rs
+++ b/lib/dag/src/lib.rs
@@ -0,0 +1,16 @@
+// typestate dag with lazy just-in-time execution
+struct States<S1,S2>(S1,S2);
+
+struct Known<T>(T);
+struct NeedsRecalculate;
+
+fn a(){
+	// Construct a DAG such that S2 depends on S1
+	// let dag=Dag:new();
+	// Initial state
+	let state=States(Known(1),Known(1));
+	// set_state1 changes S2 to NeedsRecalculate
+	state.set_state1(2);
+	// get_state2 calculates S2
+	let s2=state.get_state2();
+}
--- a/lib/rbx_loader/Cargo.toml
+++ b/lib/rbx_loader/Cargo.toml
@@ -12,7 +12,7 @@ authors = ["Rhys Lloyd <krakow20@gmail.com>"]
 [dependencies]
 bytemuck = "1.14.3"
 glam = "0.30.0"
-regex = { version = "1.11.3", default-features = false }
+regex = { version = "1.11.3", default-features = false, features = ["unicode-perl"] }
 rbx_mesh = "0.5.0"
 rbxassetid = { version = "0.1.0", path = "../rbxassetid", registry = "strafesnet" }
 roblox_emulator = { version = "0.5.1", path = "../roblox_emulator", default-features = false, registry = "strafesnet" }
--- a/lib/snf/src/newtypes/physics.rs
+++ b/lib/snf/src/newtypes/physics.rs
@@ -88,6 +88,11 @@ pub enum Instruction{
 	PracticeFly,
 	#[brw(magic=14u8)]
 	SetSensitivity(super::integer::Ratio64Vec2),
+	#[brw(magic=15u8)]
+	SetSprint(
+		#[br(map=bool_from_u8)]
+		#[bw(map=bool_into_u8)]
+		bool),
 	#[brw(magic=255u8)]
 	Idle,
 }
@@ -116,6 +121,7 @@ impl TryInto<strafesnet_common::physics::Instruction> for Instruction{
 			Instruction::SetMoveForward(state)=>strafesnet_common::physics::Instruction::SetControl(strafesnet_common::physics::SetControlInstruction::SetMoveForward(state.into())),
 			Instruction::SetJump(state)=>strafesnet_common::physics::Instruction::SetControl(strafesnet_common::physics::SetControlInstruction::SetJump(state.into())),
 			Instruction::SetZoom(state)=>strafesnet_common::physics::Instruction::SetControl(strafesnet_common::physics::SetControlInstruction::SetZoom(state.into())),
+			Instruction::SetSprint(state)=>strafesnet_common::physics::Instruction::SetControl(strafesnet_common::physics::SetControlInstruction::SetSprint(state.into())),
 			Instruction::Reset=>strafesnet_common::physics::Instruction::Mode(strafesnet_common::physics::ModeInstruction::Reset),
 			Instruction::Restart(mode_id)=>strafesnet_common::physics::Instruction::Mode(strafesnet_common::physics::ModeInstruction::Restart(strafesnet_common::gameplay_modes::ModeId::new(mode_id))),
 			Instruction::Spawn(mode_id,stage_id)=>strafesnet_common::physics::Instruction::Mode(strafesnet_common::physics::ModeInstruction::Spawn(
@@ -142,6 +148,7 @@ impl TryFrom<strafesnet_common::physics::Instruction> for Instruction{
 			strafesnet_common::physics::Instruction::SetControl(strafesnet_common::physics::SetControlInstruction::SetMoveForward(state))=>Ok(Instruction::SetMoveForward(state.into())),
 			strafesnet_common::physics::Instruction::SetControl(strafesnet_common::physics::SetControlInstruction::SetJump(state))=>Ok(Instruction::SetJump(state.into())),
 			strafesnet_common::physics::Instruction::SetControl(strafesnet_common::physics::SetControlInstruction::SetZoom(state))=>Ok(Instruction::SetZoom(state.into())),
+			strafesnet_common::physics::Instruction::SetControl(strafesnet_common::physics::SetControlInstruction::SetSprint(state))=>Ok(Instruction::SetSprint(state.into())),
 			strafesnet_common::physics::Instruction::Mode(strafesnet_common::physics::ModeInstruction::Reset)=>Ok(Instruction::Reset),
 			strafesnet_common::physics::Instruction::Mode(strafesnet_common::physics::ModeInstruction::Restart(mode_id))=>Ok(Instruction::Restart(mode_id.get())),
 			strafesnet_common::physics::Instruction::Mode(strafesnet_common::physics::ModeInstruction::Spawn(mode_id,stage_id))=>Ok(Instruction::Spawn(
--- a/strafe-client/models/suzanne.obj
+++ b/strafe-client/models/suzanne.obj
--- a/strafe-client/models/teapot.obj
+++ b/strafe-client/models/teapot.obj
--- a/strafe-client/models/teslacyberv3.0.mtl
+++ b/strafe-client/models/teslacyberv3.0.mtl
@@ -1,62 +0,0 @@
-# Blender MTL File: 'teslacyberv3.0.blend'
-# Material Count: 6
-
-newmtl Material
-Ns 65.476285
-Ka 1.000000 1.000000 1.000000
-Kd 0.411568 0.411568 0.411568
-Ks 0.614679 0.614679 0.614679
-Ke 0.000000 0.000000 0.000000
-Ni 36.750000
-d 1.000000
-illum 3
-
-newmtl Материал
-Ns 323.999994
-Ka 1.000000 1.000000 1.000000
-Kd 0.800000 0.800000 0.800000
-Ks 0.500000 0.500000 0.500000
-Ke 0.000000 0.000000 0.000000
-Ni 1.000000
-d 1.000000
-illum 2
-
-newmtl Материал.001
-Ns 900.000000
-Ka 1.000000 1.000000 1.000000
-Kd 0.026240 0.026240 0.026240
-Ks 0.000000 0.000000 0.000000
-Ke 0.000000 0.000000 0.000000
-Ni 1.450000
-d 1.000000
-illum 1
-
-newmtl Материал.002
-Ns 0.000000
-Ka 1.000000 1.000000 1.000000
-Kd 0.031837 0.032429 0.029425
-Ks 0.169725 0.169725 0.169725
-Ke 0.000000 0.000000 0.000000
-Ni 0.000000
-d 1.000000
-illum 2
-
-newmtl Материал.003
-Ns 900.000000
-Ka 1.000000 1.000000 1.000000
-Kd 0.023585 0.083235 0.095923
-Ks 1.000000 1.000000 1.000000
-Ke 0.000000 0.000000 0.000000
-Ni 45.049999
-d 1.000000
-illum 3
-
-newmtl Материал.004
-Ns 323.999994
-Ka 1.000000 1.000000 1.000000
-Kd 0.800000 0.800000 0.800000
-Ks 0.500000 0.500000 0.500000
-Ke 0.000000 0.000000 0.000000
-Ni 1.000000
-d 1.000000
-illum 2
--- a/strafe-client/models/teslacyberv3.0.obj
+++ b/strafe-client/models/teslacyberv3.0.obj
--- a/strafe-client/src/window.rs
+++ b/strafe-client/src/window.rs
@@ -15,6 +15,7 @@ pub enum Instruction{
 struct WindowContext<'a>{
 	manual_mouse_lock:bool,
 	mouse_pos:glam::DVec2,
+	simulation_paused:bool,
 	screen_size:glam::UVec2,
 	window:&'a winit::window::Window,
 	physics_thread:crate::compat_worker::QNWorker<'a,TimedInstruction<PhysicsWorkerInstruction,SessionTime>>,
@@ -24,6 +25,35 @@ impl WindowContext<'_>{
 	fn get_middle_of_screen(&self)->winit::dpi::PhysicalPosition<u32>{
 		winit::dpi::PhysicalPosition::new(self.screen_size.x/2,self.screen_size.y/2)
 	}
+	fn free_mouse(&mut self){
+		self.manual_mouse_lock=false;
+		match self.window.set_cursor_position(self.get_middle_of_screen()){
+			Ok(())=>(),
+			Err(e)=>println!("Could not set cursor position: {:?}",e),
+		}
+		match self.window.set_cursor_grab(winit::window::CursorGrabMode::None){
+			Ok(())=>(),
+			Err(e)=>println!("Could not release cursor: {:?}",e),
+		}
+		self.window.set_cursor_visible(true);
+	}
+	fn lock_mouse(&mut self){
+		//if cursor is outside window don't lock but apparently there's no get pos function
+		//let pos=window.get_cursor_pos();
+		match self.window.set_cursor_grab(winit::window::CursorGrabMode::Locked){
+			Ok(())=>(),
+			Err(_)=>{
+				match self.window.set_cursor_grab(winit::window::CursorGrabMode::Confined){
+					Ok(())=>(),
+					Err(e)=>{
+						self.manual_mouse_lock=true;
+						println!("Could not confine cursor: {:?}",e)
+					},
+				}
+			}
+		}
+		self.window.set_cursor_visible(false);
+	}
 	fn window_event(&mut self,time:SessionTime,event:winit::event::WindowEvent){
 		match event{
 			winit::event::WindowEvent::DroppedFile(path)=>{
@@ -34,6 +64,10 @@ impl WindowContext<'_>{
 				}
 			},
 			winit::event::WindowEvent::Focused(state)=>{
+				// don't unpause if manually paused
+				if self.simulation_paused{
+					return;
+				}
 				//pause unpause
 				self.physics_thread.send(TimedInstruction{
 					time,
@@ -46,35 +80,8 @@ impl WindowContext<'_>{
 				..
 			}=>{
 				match (logical_key,state){
-					(winit::keyboard::Key::Named(winit::keyboard::NamedKey::Tab),winit::event::ElementState::Pressed)=>{
-						self.manual_mouse_lock=false;
-						match self.window.set_cursor_position(self.get_middle_of_screen()){
-							Ok(())=>(),
-							Err(e)=>println!("Could not set cursor position: {:?}",e),
-						}
-						match self.window.set_cursor_grab(winit::window::CursorGrabMode::None){
-							Ok(())=>(),
-							Err(e)=>println!("Could not release cursor: {:?}",e),
-						}
-						self.window.set_cursor_visible(state.is_pressed());
-					},
-					(winit::keyboard::Key::Named(winit::keyboard::NamedKey::Tab),winit::event::ElementState::Released)=>{
-						//if cursor is outside window don't lock but apparently there's no get pos function
-						//let pos=window.get_cursor_pos();
-						match self.window.set_cursor_grab(winit::window::CursorGrabMode::Locked){
-							Ok(())=>(),
-							Err(_)=>{
-								match self.window.set_cursor_grab(winit::window::CursorGrabMode::Confined){
-									Ok(())=>(),
-									Err(e)=>{
-										self.manual_mouse_lock=true;
-										println!("Could not confine cursor: {:?}",e)
-									},
-								}
-							}
-						}
-						self.window.set_cursor_visible(state.is_pressed());
-					},
+					(winit::keyboard::Key::Named(winit::keyboard::NamedKey::Tab),winit::event::ElementState::Pressed)=>self.free_mouse(),
+					(winit::keyboard::Key::Named(winit::keyboard::NamedKey::Tab),winit::event::ElementState::Released)=>self.lock_mouse(),
 					(winit::keyboard::Key::Named(winit::keyboard::NamedKey::F11),winit::event::ElementState::Pressed)=>{
 						if self.window.fullscreen().is_some(){
 							self.window.set_fullscreen(None);
@@ -131,8 +138,18 @@ impl WindowContext<'_>{

 						if let Some(session_instruction)=match keycode{
 							winit::keyboard::Key::Named(winit::keyboard::NamedKey::Space)=>input_ctrl!(SetJump,s),
+							winit::keyboard::Key::Named(winit::keyboard::NamedKey::Shift)=>input_ctrl!(SetSprint,s),
 							// TODO: bind system so playback pausing can use spacebar
-							winit::keyboard::Key::Named(winit::keyboard::NamedKey::Enter)=>session_playback!(TogglePaused,s),
+							winit::keyboard::Key::Named(winit::keyboard::NamedKey::Enter)=>if s{
+								let paused=!self.simulation_paused;
+								self.simulation_paused=paused;
+								if paused{
+									self.free_mouse();
+								}else{
+									self.lock_mouse();
+								}
+								Some(SessionInstructionSubset::Control(SessionControlInstruction::SetPaused(paused)))
+							}else{None},
 							winit::keyboard::Key::Named(winit::keyboard::NamedKey::ArrowUp)=>session_playback!(IncreaseTimescale,s),
 							winit::keyboard::Key::Named(winit::keyboard::NamedKey::ArrowDown)=>session_playback!(DecreaseTimescale,s),
 							winit::keyboard::Key::Named(winit::keyboard::NamedKey::ArrowLeft)=>session_playback!(SkipBack,s),
@@ -241,6 +258,7 @@ pub fn worker<'a>(
 	let mut window_context=WindowContext{
 		manual_mouse_lock:false,
 		mouse_pos:glam::DVec2::ZERO,
+		simulation_paused:false,
 		//make sure to update this!!!!!
 		screen_size,
 		window,
Author	SHA1	Message	Date
Rhys Lloyd	85274abe52	idea	2026-01-28 12:22:02 -08:00
Rhys Lloyd	e59555b3e3	lib	2026-01-28 12:21:46 -08:00
Rhys Lloyd	562e46a87e	defer body update to actual strafe tick	2026-01-28 09:57:33 -08:00
Rhys Lloyd	3c13d5f8ec	untab	2026-01-28 08:40:14 -08:00
Rhys Lloyd	1f0f78f9d8	tweak Trajectory code	2026-01-28 08:39:28 -08:00
Rhys Lloyd	a90cb53a20	delete awful functions	2026-01-28 07:28:22 -08:00
Rhys Lloyd	170e2b9bce	return used contacts from push_solve	2026-01-27 09:28:26 -08:00
Rhys Lloyd	3e0fc54852	Delete Body.acceleration Field (#30 ) Acceleration is not a persistent part of the PhysicsState, and is only used for intermediate calculations along a trajectory. Fixes several bugs: - Walk decelerate clip into wall - Walk accelerate clip into wall - Fall while flying Reviewed-on: #30 Co-authored-by: Rhys Lloyd <krakow20@gmail.com> Co-committed-by: Rhys Lloyd <krakow20@gmail.com>	2026-01-27 17:08:08 +00:00
Rhys Lloyd	acea52646a	untab	2026-01-27 07:58:18 -08:00
Rhys Lloyd	7220506fd5	plumb sprint	2026-01-27 07:46:17 -08:00
Rhys Lloyd	8f94234ddc	change DirectedEdge signature	2026-01-27 07:38:45 -08:00
Rhys Lloyd	36143b8b69	change UndirectedEdge signature	2026-01-27 07:35:43 -08:00
Rhys Lloyd	3893b2f44f	work around reset bug	2026-01-26 09:19:31 -08:00
Rhys Lloyd	d62ff68baa	fix comments	2026-01-26 09:06:40 -08:00
Rhys Lloyd	2331bef281	pretty print time	2026-01-22 09:43:35 -08:00
Quaternions	31b52f7c34	Conditionally Advance Body in `atomic_internal_instruction` StrafeTick (#14 ) Closes #13, but exposes the underlying issue at all times. Reviewed-on: #14 Co-authored-by: Quaternions <krakow20@gmail.com> Co-committed-by: Quaternions <krakow20@gmail.com>	2026-01-22 17:00:52 +00:00
Rhys Lloyd	b12c495a33	it: bug 3	2026-01-22 08:57:35 -08:00
Rhys Lloyd	8329eadb18	use unbounded range in physics tests	2026-01-22 08:47:54 -08:00
Rhys Lloyd	4b2f93be66	fix algorithm setup start position	2026-01-22 08:41:54 -08:00
Rhys Lloyd	469ab48156	allow unbounded range	2026-01-22 08:41:35 -08:00
Rhys Lloyd	c2650adf54	md: simplify reduce	2026-01-21 10:32:19 -08:00
Rhys Lloyd	cdafbb4077	Implement MinimumDifference Algorithm (#25 ) Completely replace the janky closest fev crawl from infinity algorithm with a dedicated purpose-built algorithm. Finding the closest point on a MinkowskiMesh is equivalent to finding the closest point between two meshes. Reviewed-on: #25 Co-authored-by: Rhys Lloyd <krakow20@gmail.com> Co-committed-by: Rhys Lloyd <krakow20@gmail.com>	2026-01-21 17:31:52 +00:00
Rhys Lloyd	087e95b1f7	delete TogglePaused	2025-12-22 13:54:35 -08:00
Rhys Lloyd	e46a51319f	delete unused models	2025-12-20 16:31:05 -08:00
Rhys Lloyd	a3b0306430	rbx_loader: fix regex	2025-12-19 13:10:04 -08:00