Make lookup point configurable

src/bin/envmap/main.rs

@@ -15,9 +15,9 @@ fn make_viewport(w: u32, h: u32) -> [Vertex; 4] {
 	let h = h as f32;
 	let (w, h) = (1.0f32.max(w / h), 1.0f32.max(h / w));
 	let screen_coord = [vec2(-1., -1.), vec2(1., -1.), vec2(-1., 1.), vec2(1., 1.)];
-	let world_coord = [vec3(-w, -h, 0.), vec3(w, -h, 0.), vec3(-w, h, 0.), vec3(w, h, 0.)];
+	let world_coord = [vec3(-w, -h, 2.), vec3(w, -h, 2.), vec3(-w, h, 2.), vec3(w, h, 2.)];
 	[0, 1, 2, 3].map(|k| Vertex {
-		world: 10. * world_coord[k],
+		dir: world_coord[k],
 		screen: screen_coord[k],
 	})
 }
@@ -36,10 +36,8 @@ fn main() {
 	noiser.set_params(
 		&queue,
 		perlin::Params {
-			seed: 42,
-			layers: 8,
-			roughness: 0.9,
-			scale: 1.7,
+			origin: vec3(0., 0., -12.),
+			radius: 12.,
 		},
 	);
 

src/bin/envmap/perlin.rs

@@ -9,22 +9,21 @@ use glam::{Vec2, Vec3};
 #[derive(Debug, Clone, Copy, Pod, Zeroable)]
 #[repr(C)]
 pub struct Params {
-	pub seed: u32,
-	pub layers: u32,
-	pub roughness: f32,
-	pub scale: f32,
+	pub origin: Vec3,
+	pub radius: f32,
 }
 
 #[derive(Debug, Clone, Copy, Pod, Zeroable)]
 #[repr(C)]
 pub struct Vertex {
-	pub world: Vec3,
+	pub dir: Vec3,
 	pub screen: Vec2,
 }
 
 pub struct Pipeline {
 	view_buf: wgpu::Buffer,
 	params_buf: wgpu::Buffer,
+	bindings: wgpu::BindGroup,
 	pipeline: wgpu::RenderPipeline,
 }
 
@@ -66,7 +65,7 @@ impl Pipeline {
 						},
 						wgpu::VertexAttribute {
 							shader_location: 1,
-							offset: offset_of!(Vertex, world) as u64,
+							offset: offset_of!(Vertex, dir) as u64,
 							format: wgpu::VertexFormat::Float32x3,
 						},
 					],
@@ -95,9 +94,18 @@ impl Pipeline {
 			multiview: None,
 			cache: None,
 		});
+		let bindings = device.create_bind_group(&wgpu::BindGroupDescriptor {
+			label: None,
+			layout: &pipeline.get_bind_group_layout(0),
+			entries: &[wgpu::BindGroupEntry {
+				binding: 0,
+				resource: params_buf.as_entire_binding(),
+			}],
+		});
 		Self {
 			view_buf,
 			params_buf,
+			bindings,
 			pipeline,
 		}
 	}
@@ -113,6 +121,7 @@ impl Pipeline {
 	pub fn render(&self, pass: &mut wgpu::RenderPass) {
 		pass.set_pipeline(&self.pipeline);
 		pass.set_vertex_buffer(0, self.view_buf.slice(..));
+		pass.set_bind_group(0, &self.bindings, &[]);
 		pass.draw(0..4, 0..1);
 	}
 }

src/bin/envmap/perlin.wgsl

@@ -5,24 +5,31 @@ struct Params {
 	scale: f32,
 }
 
+struct LookParams {
+	origin: vec3f,
+	radius: f32,
+}
+
 struct Vertex {
 	@location(0) screen: vec2f,
-	@location(1) world: vec3f,
+	@location(1) dir: vec3f,
 }
 
 struct Varying {
-	@location(0) world: vec3f,
+	@location(0) dir: vec3f,
 	@builtin(position) screen: vec4f,
 }
 
+@group(0) @binding(0) var<uniform> params: LookParams;
+
 @vertex
 fn on_vertex(in: Vertex) -> Varying {
-	return Varying(in.world, vec4(in.screen, 0.0, 1.0));
+	return Varying(in.dir, vec4(in.screen, 0.0, 1.0));
 }
 
 @fragment
 fn on_fragment(in: Varying) -> @location(0) vec4f {
-	let point = 30. * (normalize(in.world + vec3(0., 0., 30.)) - vec3(0., 0., 1.));
+	let point = params.origin + params.radius * normalize(in.dir);
 	let sharp_area = perlin_noise(Params(1, 3, 0.9, 2.0), 0.1 * point);
 	let sharp_base = perlin_noise(Params(1, 6, 0.9, 2.0), 0.1 * point);
 	let cloud_base = perlin_noise(Params(2, 8, 0.6, 2.0), 0.1 * point);