1 files changed, 47 insertions, 0 deletions
diff --git a/wgpu/src/shader/image.wgsl b/wgpu/src/shader/image.wgsl
new file mode 100644
index 00000000..a63ee8f6
--- /dev/null
+++ b/wgpu/src/shader/image.wgsl
@@ -0,0 +1,47 @@
+[[block]]
+struct Globals {
+    transform: mat4x4<f32>;
+};
+
+[[group(0), binding(0)]] var<uniform> globals: Globals;
+[[group(0), binding(1)]] var u_sampler: sampler;
+[[group(1), binding(0)]] var u_texture: texture_2d_array<f32>;
+
+struct VertexInput {
+    [[location(0)]] v_pos: vec2<f32>;
+    [[location(1)]] pos: vec2<f32>;
+    [[location(2)]] scale: vec2<f32>;
+    [[location(3)]] atlas_pos: vec2<f32>;
+    [[location(4)]] atlas_scale: vec2<f32>;
+    [[location(5)]] layer: i32;
+};
+
+struct VertexOutput {
+    [[builtin(position)]] position: vec4<f32>;
+    [[location(0)]] uv: vec2<f32>;
+    [[location(1)]] layer: f32; // this should be an i32, but naga currently reads that as requiring interpolation.
+};
+
+[[stage(vertex)]]
+fn vs_main(input: VertexInput) -> VertexOutput {
+    var out: VertexOutput;
+
+    out.uv = vec2<f32>(input.v_pos * input.atlas_scale + input.atlas_pos);
+    out.layer = f32(input.layer);
+
+    var transform: mat4x4<f32> = mat4x4<f32>(
+        vec4<f32>(input.scale.x, 0.0, 0.0, 0.0),
+        vec4<f32>(0.0, input.scale.y, 0.0, 0.0),
+        vec4<f32>(0.0, 0.0, 1.0, 0.0),
+        vec4<f32>(input.pos, 0.0, 1.0)
+    );
+
+    out.position = globals.transform * transform * vec4<f32>(input.v_pos, 0.0, 1.0);
+
+    return out;
+}
+
+[[stage(fragment)]]
+fn fs_main(input: VertexOutput) -> [[location(0)]] vec4<f32> {
+    return textureSample(u_texture, u_sampler, input.uv, i32(input.layer));
+}