pixels/examples/custom-shader/shaders/noise.wgsl
Jay Oster c4df23f65d
Update to wgpu 0.9 (#179)
* Update to wgpu 0.9

* Fix validation error in WGSL shader

- This moves the hardcoded vertex positions and texture coordinates to
  the vertex buffer.
- Replaces the two-triangle quad to 1 full-screen triangle (fixes #180)
- Rewrites the custom shader example to fix a bug with large surface
  textures;
  - The input texture size was used for the output texture, causing the
    purple rectangle to appear very jumpy on large displays in full screen.
- The `ScalingRenderer` now exposes its clipping rectangle. The custom
  shader example uses this for its own clipping rectangle, but it can
  also be used for interacting with the border in general.

* Switch to `wgpu::include_wgsl!()`

- This is a nice little simplification.
- Thanks to @JMS55 for the suggestion!
2021-06-27 11:09:29 -07:00

51 lines
1.4 KiB
WebGPU Shading Language

// Vertex shader bindings
struct VertexOutput {
[[location(0)]] tex_coord: vec2<f32>;
[[builtin(position)]] position: vec4<f32>;
};
[[stage(vertex)]]
fn vs_main(
[[location(0)]] position: vec2<f32>,
[[location(1)]] tex_coord: vec2<f32>,
) -> VertexOutput {
var out: VertexOutput;
out.tex_coord = tex_coord;
out.position = vec4<f32>(position, 0.0, 1.0);
return out;
}
// Fragment shader bindings
[[group(0), binding(0)]] var r_tex_color: texture_2d<f32>;
[[group(0), binding(1)]] var r_tex_sampler: sampler;
[[block]] struct Locals {
time: f32;
};
[[group(0), binding(2)]] var r_locals: Locals;
let tau: f32 = 6.283185307179586476925286766559;
let bias: f32 = 0.2376; // Offset the circular time input so it is never 0
// Random functions based on https://thebookofshaders.com/10/
let random_scale: f32 = 43758.5453123;
let random_x: f32 = 12.9898;
let random_y: f32 = 78.233;
fn random(x: f32) -> f32 {
return fract(sin(x) * random_scale);
}
fn random_vec2(st: vec2<f32>) -> f32 {
return random(dot(st, vec2<f32>(random_x, random_y)));
}
[[stage(fragment)]]
fn fs_main([[location(0)]] tex_coord: vec2<f32>) -> [[location(0)]] vec4<f32> {
let sampled_color = textureSample(r_tex_color, r_tex_sampler, tex_coord);
let noise_color = vec3<f32>(random_vec2(tex_coord.xy * vec2<f32>(r_locals.time % tau + bias)));
return vec4<f32>(sampled_color.rgb * noise_color, sampled_color.a);
}