Work in progress towards 2D lighting

assets/canvas_shader.wgsl

@@ -1,12 +1,37 @@
-struct VertexOutput {
-    @builtin(position) clip_position: vec4<f32>,
+struct FragmentInput {
+    @builtin(position) fragment_coordinate: vec4<f32>,
     @location(0) world_position: vec4<f32>,
     @location(1) world_normal: vec3<f32>,
     @location(2) uv: vec2<f32>,
 };
 
+struct TileLight {
+    color: vec4<f32>,
+    intensity: f32,
+    position: vec2<f32>,
+};
+
+struct CanvasMaterial {
+    ambient_color: vec4<f32>,
+    tile_lights: array<TileLight, 256u>,
+    number_of_lights: u32,
+};
+
+
+@group(1) @binding(0)
+var<uniform> canvas_material: CanvasMaterial;
+
 @fragment
-fn fragment(input: VertexOutput) -> @location(0) vec4<f32> {
-    var output_color = vec4<f32>(input.uv, 1.0, 1.0);
+fn fragment(input: FragmentInput) -> @location(0) vec4<f32> {
+    var output_color = canvas_material.ambient_color;
+
+    var lighting = vec4<f32>();
+    for (var i: u32 = 0u; i < canvas_material.number_of_lights; i++) {
+        var luminance = canvas_material.tile_lights[i].intensity * pow(length(canvas_material.tile_lights[i].position - input.world_position.xy), -1.7) * 2.0;
+        lighting += vec4<f32>(luminance * canvas_material.tile_lights[i].color.rgb, 0.0);
+    }
+
+    output_color += lighting;
+
     return output_color;
 }