Basic texturing

Cargo.lock

@@ -3049,6 +3049,7 @@ dependencies = [
  "flo_canvas",
  "flo_draw",
  "glam 0.27.0",
+ "image",
  "itertools 0.13.0",
  "itertools-num",
  "pollster",

Cargo.toml

@@ -27,6 +27,7 @@ itertools = "0.13.0"
 wgpu = "22.1.0"
 bytemuck = { version = "1.18.0", features = ["derive"] }
 pollster = "0.3.0"
+image = {version = "0.23", default-features = false, features = ["png"] }
 
 [dev-dependencies]
 approx = "0.5.1"

src/bin/textured/main.rs

@@ -1,4 +1,5 @@
 use glam::*;
+use image::RgbImage;
 use refraction::mesh_loader::load_mesh;
 use refraction::mesh_tracer::{trace_to_mesh, Mesh};
 use show_image::event::{ElementState, VirtualKeyCode, WindowEvent};
@@ -62,7 +63,7 @@ fn ypr_to_mat(ypr: Vec3) -> Mat3 {
 	m_roll * m_pitch * m_yaw
 }
 
-fn render(mesh: &Mesh, camera: impl Fn(Vec2) -> (Vec3, Vec3)) -> Image {
+fn render(mesh: &Mesh, texture: &RgbImage, camera: impl Fn(Vec2) -> (Vec3, Vec3)) -> Image {
 	let bkg = vec3(0.0, 0.0, 0.0);
 	let mut img = Image {
 		w: W,
@@ -77,7 +78,9 @@ fn render(mesh: &Mesh, camera: impl Fn(Vec2) -> (Vec3, Vec3)) -> Image {
 			let (base, ray) = camera(off);
 			let color = if let Some(r) = trace_to_mesh(mesh, base, ray.normalize()) {
 				// to_vec3(0.45) * dot(r.normal, normalize(vec3(-1.0, 1.0, -1.0))) + 0.50
-				vec3(r.tex_coords.x, r.tex_coords.y, 0.)
+				let x = (r.tex_coords.x * texture.width() as f32) as u32;
+				let y = (r.tex_coords.y * texture.height() as f32) as u32;
+				texture.get_pixel(x, y).0.map(|channel| channel as f32 / 255.).into()
 			} else {
 				bkg
 			};
@@ -116,8 +119,8 @@ static PROJS: [fn(dist: f32, off: Vec2) -> (Vec3, Vec3); 2] = [persp, ortho];
 #[show_image::main]
 fn main() -> Result<(), Box<dyn Error>> {
 	let args: Vec<String> = env::args().collect();
-	if args.len() != 2 {
+	if args.len() != 3 {
-		println!("Usage: {} path/to/model.obj", args[0]);
+		println!("Usage: {} path/to/model.obj path/to/texture.png", args[0]);
 		exit(1);
 	}
 	let mesh = {
@@ -125,6 +128,7 @@ fn main() -> Result<(), Box<dyn Error>> {
 		let mut f = BufReader::new(f);
 		load_mesh(&mut f)?
 	};
+	let texture = image::io::Reader::open(&args[2])?.decode()?.into_rgb8();
 	let window = show_image::create_window("Raytracing", WindowOptions::default())?;
 	window.add_event_handler(|_wnd, ev, _ctl| {
 		if let WindowEvent::KeyboardInput(ev) = ev {
@@ -141,7 +145,7 @@ fn main() -> Result<(), Box<dyn Error>> {
 			let proj = PROJS[PROJ_INDEX.load(Relaxed)];
 			let m_view = ypr_to_mat(vec3((135.0 + phi as f32) * PI / 180.0, -30.0 * PI / 180.0, 0.0f32));
 			let m_camera = m_view.transpose();
-			let img = render(mesh.as_slice(), |off| {
+			let img = render(mesh.as_slice(), &texture, |off| {
 				let (base, ray) = proj(40., 20. * off);
 				(m_camera * base, m_camera * ray)
 			});