add Bvh

Cargo.lock

@@ -1883,9 +1883,9 @@ checksum = "a2eb9349b6444b326872e140eb1cf5e7c522154d69e7a0ffb0fb81c06b37543f"
 
 [[package]]
 name = "strafesnet_common"
-version = "0.8.6"
+version = "0.8.7"
 source = "sparse+https://git.itzana.me/api/packages/strafesnet/cargo/"
-checksum = "fb31424f16d189979d9f5781067ff29169a258c11da6ff46a4196bffd96d61dc"
+checksum = "ac4eb613a8d86986b61aa6b52bd74ef605d370c149778fe96cfab16dc4377636"
 dependencies = [
  "arrayvec",
  "bitflags 2.11.0",

lib/src/bot.rs

@@ -34,6 +34,10 @@ impl CompleteBot{
 	pub fn time(&self,time:PlaybackTime)->PhysicsTime{
 		self.timer.time(time)
 	}
+	pub fn playback_time(&self,time:PhysicsTime)->PlaybackTime{
+		use strafesnet_common::timer::TimerState;
+		time.coerce()-self.timer.clone().into_state().get_offset().coerce()
+	}
 	pub const fn duration(&self)->PhysicsTime{
 		self.duration
 	}

lib/src/bvh.rs

@@ -0,0 +1,101 @@
+use core::ops::Range;
+use strafesnet_common::aabb::Aabb;
+use strafesnet_common::bvh::generate_bvh;
+use strafesnet_common::integer::vec3;
+use strafesnet_common::integer::Fixed;
+use strafesnet_common::physics::Time as PhysicsTime;
+use crate::bot::CompleteBot;
+
+const MAX_SLICE_LEN:usize=16;
+struct EventSlice(Range<usize>);
+
+pub struct Bvh{
+	bvh:strafesnet_common::bvh::BvhNode<EventSlice>,
+}
+
+impl Bvh{
+	pub fn new(bot:&CompleteBot)->Self{
+		let output_events=&bot.timelines().output_events;
+		// iterator over the event timeline and capture slices of contiguous output events.
+		// create an Aabb for each slice and then generate a BVH.
+		let mut bvh_nodes=Vec::new();
+		let it=output_events
+			.array_windows()
+			.enumerate()
+			// find discontinuities
+			.filter(|&(_,[event0,event1])|
+				event0.time==event1.time&&!(
+					event0.event.position.x==event0.event.position.x
+					&&event0.event.position.y==event0.event.position.y
+					&&event0.event.position.z==event0.event.position.z
+				)
+			);
+
+		let mut last_index=0;
+		let mut push_slices=|index:usize|{
+			let len=index-last_index;
+			let count=len.div_ceil(MAX_SLICE_LEN);
+			let slice_len=len/count;
+			bvh_nodes.reserve(count);
+			// 0123456789
+			// last_index=0
+			// split_index=9
+			// index=10
+			// len=10
+			// count=3
+			// node_len=4
+			// split into groups of 4
+			// [0123][4567][89]
+			let mut push_slice=|slice:Range<usize>|{
+				let mut aabb=Aabb::default();
+				for event in &output_events[slice.start..slice.end]{
+					aabb.grow(vec3::try_from_f32_array([event.event.position.x,event.event.position.y,event.event.position.z]).unwrap());
+				}
+				bvh_nodes.push((EventSlice(slice),aabb));
+			};
+			// push fixed-size groups
+			for i in 0..count-1{
+				push_slice((last_index+i*slice_len)..(last_index+(i+1)*slice_len));
+			}
+			// push last group which may be shorter
+			push_slice((last_index+(count-1)*slice_len)..index);
+			last_index=index;
+		};
+		// find discontinuities (teleports) and avoid forming a bvh node across them
+		for (split_index,_) in it{
+			// we want to use the index of event1
+			push_slices(split_index+1);
+		}
+		// there are no more discontinuities, push the remaining slices
+		push_slices(output_events.len());
+		let bvh=generate_bvh(bvh_nodes);
+		Self{bvh}
+	}
+	/// Find the exact timestamp on the bot timeline that is closest to the given point.
+	pub fn closest_time_to_point(&self,bot:&CompleteBot,point:glam::Vec3)->Option<PhysicsTime>{
+		let start_point=vec3::try_from_f32_array(point.to_array()).unwrap();
+		let output_events=&bot.timelines().output_events;
+		// grow a sphere starting at start_point until we find the closest point on the bot output events
+		let intersect_leaf=|leaf:&EventSlice|{
+			// calculate the distance to the leaf contents
+			output_events[leaf.0.start..leaf.0.end].iter().map(|event|{
+				let p=event.event.position;
+				let p=vec3::try_from_f32_array([p.x,p.y,p.z]).unwrap();
+				(start_point-p).length_squared()
+			}).min()
+		};
+		let intersect_aabb=|aabb:&Aabb|{
+			// calculate the distance to the aabb
+			let clamped_point=start_point.min(aabb.max()).max(aabb.min());
+			Some((start_point-clamped_point).length_squared())
+		};
+		let (_,leaf)=self.bvh.traverse(start_point,Fixed::ZERO,Fixed::MAX,intersect_leaf,intersect_aabb)?;
+		let closest_event=output_events[leaf.0.start..leaf.0.end].iter().min_by_key(|&event|{
+			let p=event.event.position;
+			let p=vec3::try_from_f32_array([p.x,p.y,p.z]).unwrap();
+			(start_point-p).length_squared()
+		})?;
+		// TODO: project start_point onto the edges connected to the closest_event and return the true time
+		crate::time::from_float(closest_event.time).ok()
+	}
+}

lib/src/head.rs

@@ -119,6 +119,10 @@ impl PlaybackHead{
 
 		(p-bot.world_offset()+CompleteBot::CAMERA_OFFSET,a.yx())
 	}
+	pub fn get_position(&self,bot:&CompleteBot,time:SessionTime)->glam::Vec3{
+		let interp=self.interpolate_output(bot,time);
+		interp.position()
+	}
 	pub fn get_velocity(&self,bot:&CompleteBot,time:SessionTime)->glam::Vec3{
 		let interp=self.interpolate_output(bot,time);
 		interp.velocity()

lib/src/lib.rs

@@ -1,4 +1,5 @@
 pub mod bot;
+pub mod bvh;
 pub mod head;
 pub mod time;
 pub mod state;

wasm-module/src/lib.rs

@@ -1,7 +1,7 @@
 use wasm_bindgen::prelude::wasm_bindgen;
 use wasm_bindgen::JsError;
 use strafesnet_roblox_bot_file::v0;
-use strafesnet_roblox_bot_player::{bot,head,time,graphics};
+use strafesnet_roblox_bot_player::{bot,bvh,head,time,graphics};
 use strafesnet_graphics::{setup,surface};
 
 // Hack to keep the code compiling,
@@ -193,9 +193,43 @@ impl PlaybackHead{
 	pub fn get_game_controls(&self)->u32{
 		self.head.state().get_controls().bits()
 	}
+	#[wasm_bindgen]
+	pub fn get_position(&self,bot:&CompleteBot,time:f64)->Vector3{
+		let time=time::from_float(time).unwrap();
+		let position=self.head.get_position(&bot.bot,time);
+		Vector3(position)
+	}
 	/// Returns the camera angles yaw delta between the last game tick and the most recent game tick.
 	#[wasm_bindgen]
 	pub fn get_angles_yaw_delta(&self)->f32{
 		self.head.state().get_angles_delta().y
 	}
 }
+
+#[wasm_bindgen]
+pub struct Vector3(glam::Vec3);
+#[wasm_bindgen]
+impl Vector3{
+	#[wasm_bindgen]
+	pub fn to_array(&self)->Vec<f32>{
+		self.0.to_array().to_vec()
+	}
+}
+
+#[wasm_bindgen]
+pub struct Bvh{
+	bvh:bvh::Bvh,
+}
+#[wasm_bindgen]
+impl Bvh{
+	#[wasm_bindgen(constructor)]
+	pub fn new(bot:&CompleteBot)->Self{
+		Self{
+			bvh:bvh::Bvh::new(&bot.bot),
+		}
+	}
+	#[wasm_bindgen]
+	pub fn closest_time_to_point(&self,bot:&CompleteBot,point:&Vector3)->Option<f64>{
+		Some(bot.bot.playback_time(self.bvh.closest_time_to_point(&bot.bot,point.0)?).into())
+	}
+}