concinnity_core/
platform.rs

1//! The shader `Platform` vocabulary: which shader source language a rendering
2//! backend consumes. The enum is pure data with no ambient resolution of its
3//! own, so it sits in the runtime foundation and every caller states the
4//! platform it means -- the engine names the backend it was built for, and the
5//! build pipeline is told the backend it cooks for.
6
7/// Shader source language families supported by the engine. Each variant
8/// matches one render backend: Metal, HLSL (DirectX), or GLSL (Vulkan).
9#[derive(Debug, Clone, Copy, PartialEq, Eq)]
10pub enum Platform {
11    /// Metal Shading Language, for the Metal backend.
12    Metal,
13    /// HLSL, for the DirectX backend.
14    Hlsl,
15    /// GLSL, for the Vulkan backend.
16    Glsl,
17}
18
19impl Platform {
20    /// String key used in the `sources` map of a `Shader` stage.
21    pub fn key(self) -> &'static str {
22        match self {
23            Platform::Metal => "metal",
24            Platform::Hlsl => "hlsl",
25            Platform::Glsl => "glsl",
26        }
27    }
28
29    /// Whether a shader source with the given file extension is usable on this
30    /// platform. The matching extension (`metal` / `hlsl` / `glsl`) is accepted;
31    /// a non-matching shader extension is rejected so a single-path source
32    /// authored for one backend doesn't get fed to another; an unknown
33    /// extension is accepted by default (the build step surfaces a real compile
34    /// error later if the file truly can't be built).
35    ///
36    /// Shared by the per-platform source selection of `Shader` stages and
37    /// `SdfVolume` so both apply identical fallback rules.
38    pub fn accepts_ext(self, ext: &str) -> bool {
39        !matches!(ext, "metal" | "hlsl" | "glsl") || ext == self.key()
40    }
41}
42
43#[cfg(test)]
44mod tests {
45    use super::*;
46
47    #[test]
48    fn platform_key_and_accepts_ext_cover_all_variants() {
49        assert_eq!(Platform::Metal.key(), "metal");
50        assert_eq!(Platform::Hlsl.key(), "hlsl");
51        assert_eq!(Platform::Glsl.key(), "glsl");
52
53        // The matching extension is accepted; another backend's shader
54        // extension is rejected; an unknown extension is accepted by default.
55        assert!(Platform::Metal.accepts_ext("metal"));
56        assert!(!Platform::Metal.accepts_ext("hlsl"));
57        assert!(!Platform::Metal.accepts_ext("glsl"));
58        assert!(Platform::Hlsl.accepts_ext("hlsl"));
59        assert!(!Platform::Hlsl.accepts_ext("metal"));
60        assert!(Platform::Glsl.accepts_ext("glsl"));
61        assert!(!Platform::Glsl.accepts_ext("hlsl"));
62        assert!(Platform::Metal.accepts_ext("txt"));
63    }
64}
concinnity_core/platform.rs

concinnity_core/
platform.rs
