// Depth update shader for depth peeling.
// Reads depth-as-color from the peel pass and outputs it.
// The pipeline uses Max blend to keep the furthest depth.
struct VertexOutput {
@builtin(position) position: vec4<f32>,
@location(0) uv: vec2<f32>,
}
@group(0) @binding(0) var t_depth_color: texture_2d<f32>;
// Fullscreen triangle vertices
@vertex
fn vs_main(@builtin(vertex_index) vertex_index: u32) -> VertexOutput {
var positions = array<vec2<f32>, 3>(
vec2<f32>(-1.0, -1.0),
vec2<f32>(3.0, -1.0),
vec2<f32>(-1.0, 3.0)
);
var uvs = array<vec2<f32>, 3>(
vec2<f32>(0.0, 1.0),
vec2<f32>(2.0, 1.0),
vec2<f32>(0.0, -1.0)
);
var output: VertexOutput;
output.position = vec4<f32>(positions[vertex_index], 0.0, 1.0);
output.uv = uvs[vertex_index];
return output;
}
@fragment
fn fs_main(in: VertexOutput) -> @location(0) vec4<f32> {
let dims = textureDimensions(t_depth_color);
let coords = vec2<i32>(in.uv * vec2<f32>(dims));
let depth = textureLoad(t_depth_color, coords, 0).r;
return vec4<f32>(depth, 0.0, 0.0, 1.0);
}