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sable_gpu/
shader.rs

1//! Shader loading and management.
2
3use std::borrow::Cow;
4
5use wgpu::{Device, ShaderModule, ShaderModuleDescriptor, ShaderSource};
6
7/// A GPU shader module.
8#[derive(Debug)]
9pub struct Shader {
10    module: ShaderModule,
11}
12
13impl Shader {
14    /// Create a shader from WGSL source code.
15    #[must_use]
16    pub fn from_wgsl(device: &Device, source: &str, label: Option<&str>) -> Self {
17        let module = device.create_shader_module(ShaderModuleDescriptor {
18            label,
19            source: ShaderSource::Wgsl(Cow::Borrowed(source)),
20        });
21
22        Self { module }
23    }
24
25    /// Create a shader from WGSL source code with an owned string.
26    #[must_use]
27    pub fn from_wgsl_owned(device: &Device, source: String, label: Option<&str>) -> Self {
28        let module = device.create_shader_module(ShaderModuleDescriptor {
29            label,
30            source: ShaderSource::Wgsl(Cow::Owned(source)),
31        });
32
33        Self { module }
34    }
35
36    /// Get a reference to the underlying shader module.
37    #[must_use]
38    pub fn module(&self) -> &ShaderModule {
39        &self.module
40    }
41}
42
43/// Default triangle shader source.
44pub const TRIANGLE_SHADER: &str = r"
45struct VertexInput {
46    @location(0) position: vec3<f32>,
47    @location(1) color: vec3<f32>,
48}
49
50struct VertexOutput {
51    @builtin(position) clip_position: vec4<f32>,
52    @location(0) color: vec3<f32>,
53}
54
55@vertex
56fn vs_main(in: VertexInput) -> VertexOutput {
57    var out: VertexOutput;
58    out.clip_position = vec4<f32>(in.position, 1.0);
59    out.color = in.color;
60    return out;
61}
62
63@fragment
64fn fs_main(in: VertexOutput) -> @location(0) vec4<f32> {
65    return vec4<f32>(in.color, 1.0);
66}
67";