comments

engine/physics/src/model.rs

@@ -484,6 +484,9 @@ impl TransformedMesh<'_>{
 	pub fn verts<'a>(&'a self)->impl Iterator<Item=vec3::Vector3<Fixed<2,64>>>+'a{
 		self.view.data.verts.iter().map(|&Vert(pos)|self.transform.vertex.transform_point3(pos))
 	}
+	pub fn faces(&self)->impl Iterator<Item=SubmeshFaceId>{
+		(0..self.view.topology.faces.len() as u32).map(SubmeshFaceId::new)
+	}
 	fn farthest_vert(&self,dir:Planar64Vec3)->SubmeshVertId{
 		//this happens to be well-defined.  there are no virtual virtices
 		SubmeshVertId::new(

engine/physics/src/physics.rs

@@ -1,4 +1,5 @@
 use std::collections::{HashMap,HashSet};
+use crate::model::DirectedEdge;
 use crate::model::{self as model_physics,PhysicsMesh,PhysicsMeshTransform,TransformedMesh,MeshQuery,PhysicsMeshId,PhysicsSubmeshId};
 use strafesnet_common::bvh;
 use strafesnet_common::map;
@@ -280,7 +281,8 @@ impl PhysicsCamera{
 		.clamp(Self::ANGLE_PITCH_LOWER_LIMIT,Self::ANGLE_PITCH_UPPER_LIMIT);
 		mat3::from_rotation_yx(ax,ay)
 	}
-	fn rotation(&self)->Planar64Mat3{
+	#[inline]
+	pub fn rotation(&self)->Planar64Mat3{
 		self.get_rotation(self.clamped_mouse_pos)
 	}
 	fn simulate_move_rotation(&self,mouse_delta:glam::IVec2)->Planar64Mat3{
@@ -980,6 +982,34 @@ impl PhysicsContext<'_>{
 	}
 }
 impl PhysicsData{
+	pub fn trace_ray(&self,ray:strafesnet_common::ray::Ray)->Option<ModelId>{
+		let (_time,convex_mesh_id)=self.bvh.sample_ray(&ray,Time::ZERO,Time::MAX/4,|&model,ray|{
+			let mesh=self.models.mesh(model);
+			// brute force trace every face
+			mesh.faces().filter_map(|face_id|{
+				let (n,d)=mesh.face_nd(face_id);
+				// trace ray onto face
+				// n.(o+d*t)==n.p
+				// n.o + n.d * t == n.p
+				// t == (n.p - n.o)/n.d
+				let nd=n.dot(ray.direction);
+				if nd.is_zero(){
+					return None;
+				}
+				let t=(d-n.dot(ray.origin))/nd;
+				// check if point of intersection is behind face edges
+				// *2 because average of 2 vertices
+				let p=ray.extrapolate(t)*2;
+				mesh.face_edges(face_id).iter().all(|&directed_edge_id|{
+					let edge_n=mesh.directed_edge_n(directed_edge_id);
+					let cross_n=edge_n.cross(n);
+					let &[vert0,vert1]=mesh.edge_verts(directed_edge_id.as_undirected()).as_ref();
+					cross_n.dot(p)<cross_n.dot(mesh.vert(vert0)+mesh.vert(vert1))
+				}).then(||t)
+			}).min().map(Into::into)
+		})?;
+		Some(convex_mesh_id.model_id.into())
+	}
 	/// use with caution, this is the only non-instruction way to mess with physics
 	pub fn generate_models(&mut self,map:&map::CompleteMap){
 		let mut modes=map.modes.clone();

engine/physics/src/push_solve.rs

@@ -1,4 +1,6 @@
-use strafesnet_common::integer::{self,vec3::{self,Vector3},Fixed,Planar64,Planar64Vec3,Ratio};
+use strafesnet_common::integer::vec3::{self,Vector3};
+use strafesnet_common::integer::{Fixed,Planar64Vec3,Ratio};
+use strafesnet_common::ray::Ray;
 
 // This algorithm is based on Lua code
 // written by Trey Reynolds in 2021
@@ -12,24 +14,6 @@ type Conts<'a>=arrayvec::ArrayVec<&'a Contact,4>;
 // hack to allow comparing ratios to zero
 const RATIO_ZERO:Ratio<Fixed<1,32>,Fixed<1,32>>=Ratio::new(Fixed::ZERO,Fixed::EPSILON);
 
-struct Ray{
-	origin:Planar64Vec3,
-	direction:Planar64Vec3,
-}
-impl Ray{
-	fn extrapolate<Num,Den,N1,T1>(&self,t:Ratio<Num,Den>)->Planar64Vec3
-	where
-		Num:Copy,
-		Den:Copy,
-		Num:core::ops::Mul<Planar64,Output=N1>,
-		Planar64:core::ops::Mul<Den,Output=N1>,
-		N1:integer::Divide<Den,Output=T1>,
-		T1:integer::Fix<Planar64>,
-	{
-		self.origin+self.direction.map(|elem|(t*elem).divide().fix())
-	}
-}
-
 /// Information about a contact restriction
 pub struct Contact{
 	pub position:Planar64Vec3,

engine/session/src/session.rs

@@ -161,6 +161,7 @@ pub struct Session{
 	recording:Recording,
 	//players:HashMap<PlayerId,Simulation>,
 	replays:HashMap<BotId,Replay>,
+	last_ray_hit:Option<strafesnet_common::model::ModelId>,
 }
 impl Session{
 	pub fn new(
@@ -177,6 +178,7 @@ impl Session{
 			view_state:ViewState::Play,
 			recording:Default::default(),
 			replays:HashMap::new(),
+			last_ray_hit:None,
 		}
 	}
 	fn clear_recording(&mut self){
@@ -194,6 +196,19 @@ impl Session{
 			),
 		}
 	}
+	pub fn debug_raycast_print_model_id_if_changed(&mut self,time:SessionTime){
+		if let Some(frame_state)=self.get_frame_state(time){
+			let ray=strafesnet_common::ray::Ray{
+				origin:frame_state.body.extrapolated_position(self.simulation.timer.time(time)),
+				direction:-frame_state.camera.rotation().z_axis,
+			};
+			let model_id=self.geometry_shared.trace_ray(ray);
+			if model_id!=self.last_ray_hit{
+				println!("hit={model_id:?}");
+				self.last_ray_hit=model_id;
+			}
+		}
+	}
 	pub fn user_settings(&self)->&UserSettings{
 		&self.user_settings
 	}

lib/common/src/aabb.rs

@@ -34,6 +34,10 @@ impl Aabb{
 		self.min-=hs;
 		self.max+=hs;
 	}
+	pub fn contains(&self,point:Planar64Vec3)->bool{
+		let bvec=self.min.lt(point)&point.lt(self.max);
+		bvec.all()
+	}
 	pub fn intersects(&self,aabb:&Aabb)->bool{
 		let bvec=self.min.lt(aabb.max)&aabb.min.lt(self.max);
 		bvec.all()

lib/common/src/bvh.rs

@@ -1,4 +1,10 @@
+use std::cmp::Ordering;
+use std::collections::BTreeMap;
+
 use crate::aabb::Aabb;
+use crate::ray::Ray;
+use crate::integer::{Ratio,Planar64};
+use crate::instruction::{InstructionCollector,TimedInstruction};
 
 //da algaritum
 //lista boxens
@@ -10,6 +16,96 @@ use crate::aabb::Aabb;
 //sort the centerpoints on each axis (3 lists)
 //bv is put into octant based on whether it is upper or lower in each list
 
+
+pub fn intersect_aabb(ray:&Ray,aabb:&Aabb)->Option<Ratio<Planar64,Planar64>>{
+	// n.(o+d*t)==n.p
+	// n.o + n.d * t == n.p
+	// t == (n.p - n.o)/n.d
+	let mut hit=None;
+	match ray.direction.x.cmp(&Planar64::ZERO){
+		Ordering::Less=>{
+			let rel_min=aabb.min()-ray.origin;
+			let rel_max=aabb.max()-ray.origin;
+			let dy=rel_max.x*ray.direction.y;
+			let dz=rel_max.x*ray.direction.z;
+			// x is negative, so inequalities are flipped
+			if rel_min.y*ray.direction.x>dy&&dy>rel_max.y*ray.direction.x
+			 &&rel_min.z*ray.direction.x>dz&&dz>rel_max.z*ray.direction.x{
+				let t=rel_max.x/ray.direction.x;
+				hit=Some(hit.map_or(t,|best_t|t.min(best_t)));
+			}
+		},
+		Ordering::Equal=>(),
+		Ordering::Greater=>{
+			let rel_min=aabb.min()-ray.origin;
+			let rel_max=aabb.max()-ray.origin;
+			let dy=rel_min.x*ray.direction.y;
+			let dz=rel_min.x*ray.direction.z;
+			// x is positive, so inequalities are normal
+			if rel_min.y*ray.direction.x<dy&&dy<rel_max.y*ray.direction.x
+			 &&rel_min.z*ray.direction.x<dz&&dz<rel_max.z*ray.direction.x{
+				let t=rel_min.x/ray.direction.x;
+				hit=Some(hit.map_or(t,|best_t|t.min(best_t)));
+			}
+		},
+	}
+	match ray.direction.z.cmp(&Planar64::ZERO){
+		Ordering::Less=>{
+			let rel_min=aabb.min()-ray.origin;
+			let rel_max=aabb.max()-ray.origin;
+			let dx=rel_max.z*ray.direction.x;
+			let dy=rel_max.z*ray.direction.y;
+			// z is negative, so inequalities are flipped
+			if rel_min.x*ray.direction.z>dx&&dx>rel_max.x*ray.direction.z
+			 &&rel_min.y*ray.direction.z>dy&&dy>rel_max.y*ray.direction.z{
+				let t=rel_max.z/ray.direction.z;
+				hit=Some(hit.map_or(t,|best_t|t.min(best_t)));
+			}
+		},
+		Ordering::Equal=>(),
+		Ordering::Greater=>{
+			let rel_min=aabb.min()-ray.origin;
+			let rel_max=aabb.max()-ray.origin;
+			let dx=rel_min.z*ray.direction.x;
+			let dy=rel_min.z*ray.direction.y;
+			// z is positive, so inequalities are normal
+			if rel_min.x*ray.direction.z<dx&&dx<rel_max.x*ray.direction.z
+			 &&rel_min.y*ray.direction.z<dy&&dy<rel_max.y*ray.direction.z{
+				let t=rel_min.z/ray.direction.z;
+				hit=Some(hit.map_or(t,|best_t|t.min(best_t)));
+			}
+		},
+	}
+	match ray.direction.y.cmp(&Planar64::ZERO){
+		Ordering::Less=>{
+			let rel_min=aabb.min()-ray.origin;
+			let rel_max=aabb.max()-ray.origin;
+			let dz=rel_max.y*ray.direction.z;
+			let dx=rel_max.y*ray.direction.x;
+			// y is negative, so inequalities are flipped
+			if rel_min.z*ray.direction.y>dz&&dz>rel_max.z*ray.direction.y
+			 &&rel_min.x*ray.direction.y>dx&&dx>rel_max.x*ray.direction.y{
+				let t=rel_max.y/ray.direction.y;
+				hit=Some(hit.map_or(t,|best_t|t.min(best_t)));
+			}
+		},
+		Ordering::Equal=>(),
+		Ordering::Greater=>{
+			let rel_min=aabb.min()-ray.origin;
+			let rel_max=aabb.max()-ray.origin;
+			let dz=rel_min.y*ray.direction.z;
+			let dx=rel_min.y*ray.direction.x;
+			// y is positive, so inequalities are normal
+			if rel_min.z*ray.direction.y<dz&&dz<rel_max.z*ray.direction.y
+			 &&rel_min.x*ray.direction.y<dx&&dx<rel_max.x*ray.direction.y{
+				let t=rel_min.y/ray.direction.y;
+				hit=Some(hit.map_or(t,|best_t|t.min(best_t)));
+			}
+		},
+	}
+	hit
+}
+
 pub enum RecursiveContent<N,L>{
 	Branch(Vec<N>),
 	Leaf(L),
@@ -44,6 +140,92 @@ impl<L> BvhNode<L>{
 			},
 		}
 	}
+	fn populate_nodes<'a,T,F>(
+		&'a self,
+		collector:&mut InstructionCollector<&'a L,Ratio<Planar64,Planar64>>,
+		nodes:&mut BTreeMap<Ratio<Planar64,Planar64>,&'a BvhNode<L>>,
+		ray:&Ray,
+		start_time:Ratio<Planar64,Planar64>,
+		f:&F,
+	)
+		where
+			T:Ord+Copy,
+			Ratio<Planar64,Planar64>:From<T>,
+			F:Fn(&L,&Ray)->Option<T>,
+	{
+		match &self.content{
+			RecursiveContent::Leaf(leaf)=>if let Some(time)=f(leaf,ray){
+				let ins=TimedInstruction{time:time.into(),instruction:leaf};
+				if start_time.lt_ratio(ins.time)&&ins.time.lt_ratio(collector.time()){
+					collector.collect(Some(ins));
+				}
+			},
+			RecursiveContent::Branch(children)=>for child in children{
+				if child.aabb.contains(ray.origin){
+					child.populate_nodes(collector,nodes,ray,start_time,f);
+				}else{
+					// Am I an upcoming superstar?
+					if let Some(t)=intersect_aabb(ray,&child.aabb){
+						if start_time.lt_ratio(t)&&t.lt_ratio(collector.time()){
+							nodes.insert(t,child);
+						}
+					}
+				}
+			},
+		}
+	}
+	pub fn sample_ray<T,F>(
+		&self,
+		ray:&Ray,
+		start_time:T,
+		time_limit:T,
+		f:F,
+	)->Option<(T,&L)>
+		where
+			T:Ord+Copy,
+			T:From<Ratio<Planar64,Planar64>>,
+			Ratio<Planar64,Planar64>:From<T>,
+			F:Fn(&L,&Ray)->Option<T>,
+	{
+		// source of nondeterminism when Aabb boundaries are coplanar
+		let mut nodes=BTreeMap::new();
+
+		let start_time=start_time.into();
+		let time_limit=time_limit.into();
+		let mut collector=InstructionCollector::new(time_limit);
+		// break open all nodes that contain ray.origin and populate nodes with future intersection times
+		self.populate_nodes(&mut collector,&mut nodes,ray,start_time,&f);
+
+		// swim through nodes one at a time
+		while let Some((t,node))=nodes.pop_first(){
+			if collector.time()<t{
+				break;
+			}
+			match &node.content{
+				RecursiveContent::Leaf(leaf)=>if let Some(time)=f(leaf,ray){
+					let ins=TimedInstruction{time:time.into(),instruction:leaf};
+					// this lower bound can also be omitted
+					// but it causes type inference errors lol
+					if start_time.lt_ratio(ins.time)&&ins.time.lt_ratio(collector.time()){
+						collector.collect(Some(ins));
+					}
+				},
+				// break open the node and predict collisions with the child nodes
+				RecursiveContent::Branch(children)=>for child in children{
+					// Am I an upcoming superstar?
+					if let Some(t)=intersect_aabb(ray,&child.aabb){
+						// we don't need to check the lower bound
+						// because child aabbs are guaranteed to be within the parent bounds.
+						if t<collector.time(){
+							nodes.insert(t,child);
+						}
+					}
+				},
+			}
+		}
+
+		collector.take().map(|TimedInstruction{time,instruction:leaf}|(time.into(),leaf))
+	}
 	pub fn into_inner(self)->(RecursiveContent<BvhNode<L>,L>,Aabb){
 		(self.content,self.aabb)
 	}

lib/common/src/integer.rs

@@ -4,11 +4,11 @@ pub use ratio_ops::ratio::{Ratio,Divide};
 //integer units
 
 /// specific example of a "default" time type
-#[derive(Clone,Copy,Hash,Eq,PartialEq,PartialOrd,Debug)]
+#[derive(Clone,Copy,Hash,Eq,PartialEq,Ord,PartialOrd,Debug)]
 pub enum TimeInner{}
 pub type AbsoluteTime=Time<TimeInner>;
 
-#[derive(Clone,Copy,Hash,Eq,PartialEq,PartialOrd,Debug)]
+#[derive(Clone,Copy,Hash,Eq,PartialEq,Ord,PartialOrd,Debug)]
 pub struct Time<T>(i64,core::marker::PhantomData<T>);
 impl<T> Time<T>{
 	pub const MIN:Self=Self::raw(i64::MIN);

lib/common/src/lib.rs

@@ -1,5 +1,6 @@
 pub mod bvh;
 pub mod map;
+pub mod ray;
 pub mod run;
 pub mod aabb;
 pub mod model;

lib/common/src/physics.rs

@@ -1,7 +1,7 @@
 use crate::mouse::MouseState;
 use crate::gameplay_modes::{ModeId,StageId};
 
-#[derive(Clone,Copy,Hash,Eq,PartialEq,PartialOrd,Debug)]
+#[derive(Clone,Copy,Hash,Eq,PartialEq,Ord,PartialOrd,Debug)]
 pub enum TimeInner{}
 pub type Time=crate::integer::Time<TimeInner>;
 

lib/common/src/ray.rs

@@ -0,0 +1,20 @@
+use ratio_ops::ratio::Ratio;
+use crate::integer::{self,Planar64,Planar64Vec3};
+
+pub struct Ray{
+	pub origin:Planar64Vec3,
+	pub direction:Planar64Vec3,
+}
+impl Ray{
+	pub fn extrapolate<Num,Den,N1,T1>(&self,t:Ratio<Num,Den>)->Planar64Vec3
+	where
+		Num:Copy,
+		Den:Copy,
+		Num:core::ops::Mul<Planar64,Output=N1>,
+		Planar64:core::ops::Mul<Den,Output=N1>,
+		N1:integer::Divide<Den,Output=T1>,
+		T1:integer::Fix<Planar64>,
+	{
+		self.origin+self.direction.map(|elem|(t*elem).divide().fix())
+	}
+}

lib/common/src/run.rs

@@ -2,7 +2,7 @@ use crate::timer::{TimerFixed,Realtime,Paused,Unpaused};
 
 use crate::physics::{TimeInner as PhysicsTimeInner,Time as PhysicsTime};
 
-#[derive(Clone,Copy,Hash,Eq,PartialEq,PartialOrd,Debug)]
+#[derive(Clone,Copy,Hash,Eq,PartialEq,Ord,PartialOrd,Debug)]
 pub enum TimeInner{}
 pub type Time=crate::integer::Time<TimeInner>;
 

lib/common/src/session.rs

@@ -1,3 +1,3 @@
-#[derive(Clone,Copy,Hash,Eq,PartialEq,PartialOrd,Debug)]
+#[derive(Clone,Copy,Hash,Eq,PartialEq,Ord,PartialOrd,Debug)]
 pub enum TimeInner{}
 pub type Time=crate::integer::Time<TimeInner>;

lib/ratio_ops/src/ratio.rs

@@ -268,30 +268,35 @@ impl<LhsNum,LhsDen,RhsNum,RhsDen,T,U> PartialEq<Ratio<RhsNum,RhsDen>> for Ratio<
 }
 impl<Num,Den> Eq for Ratio<Num,Den> where Self:PartialEq{}
 
+// Wow! These were both completely wrong!
+// Idea: use a 'signed' trait instead of parity and float the sign to the numerator.
 impl<LhsNum,LhsDen,RhsNum,RhsDen,T,U> PartialOrd<Ratio<RhsNum,RhsDen>> for Ratio<LhsNum,LhsDen>
 	where
 		LhsNum:Copy,
-		LhsDen:Copy,
+		LhsDen:Copy+Parity,
 		RhsNum:Copy,
-		RhsDen:Copy,
+		RhsDen:Copy+Parity,
 		LhsNum:core::ops::Mul<RhsDen,Output=T>,
+		LhsDen:core::ops::Mul<RhsNum,Output=T>,
 		RhsNum:core::ops::Mul<LhsDen,Output=U>,
-		T:PartialOrd<U>,
+		RhsDen:core::ops::Mul<LhsNum,Output=U>,
+		T:PartialOrd<U>+Ord,
 {
 	#[inline]
-	fn partial_cmp(&self,other:&Ratio<RhsNum,RhsDen>)->Option<core::cmp::Ordering>{
-		(self.num*other.den).partial_cmp(&(other.num*self.den))
+	fn partial_cmp(&self,&other:&Ratio<RhsNum,RhsDen>)->Option<core::cmp::Ordering>{
+		self.partial_cmp_ratio(other)
 	}
 }
 impl<Num,Den,T> Ord for Ratio<Num,Den>
 	where
 		Num:Copy,
-		Den:Copy,
+		Den:Copy+Parity,
 		Num:core::ops::Mul<Den,Output=T>,
+		Den:core::ops::Mul<Num,Output=T>,
 		T:Ord,
 {
 	#[inline]
-	fn cmp(&self,other:&Self)->std::cmp::Ordering{
-		(self.num*other.den).cmp(&(other.num*self.den))
+	fn cmp(&self,&other:&Self)->std::cmp::Ordering{
+		self.cmp_ratio(other)
 	}
 }

strafe-client/src/physics_worker.rs

@@ -77,5 +77,8 @@ pub fn new<'a>(
 				run_session_instruction!(ins.time,SessionInstruction::LoadReplay(bot));
 			}
 		}
+
+		//whatever just do it
+		session.debug_raycast_print_model_id_if_changed(ins.time);
 	})
 }