Added skybox to renderer and reflections to shader. Builds and runs. Flickering with many objects in scene, assuming swap chain issue.

src/assets/SimpleShader.wgsl

@@ -4,16 +4,26 @@ struct Environment {
     dir: vec4<f32>,
 }
 
-struct View {
+struct Eye {
+    // from camera to screen
+    proj: mat4x4<f32>,
+    // from screen to camera
+    inv: mat4x4<f32>,
+    // world to camera
     view: mat4x4<f32>,
+    // camera transform
     frame: mat4x4<f32>,
 }
 
 // Vertex shader
 @group(0) @binding(0)
-var<uniform> view: View;
+var<uniform> eye: Eye;
 @group(0) @binding(1)
 var<uniform> environment: Environment;
+@group(0) @binding(2)
+var sky_sampler: sampler;
+@group(0) @binding(3)
+var sky_texture: texture_2d<f32>;
 
 struct VertexInput {
     @location(0) position: vec3<f32>,
@@ -60,7 +70,7 @@ fn vs_main(
     out.world_normal = model_rot_matrix * model.normal;
     var world_position: vec4<f32> = model_matrix * vec4<f32>(model.position, 1.0);
     out.world_position = world_position.xyz;
-    out.clip_position = view.view * world_position;
+    out.clip_position = eye.proj * eye.view * world_position;
     return out;
 }
 
@@ -75,23 +85,79 @@ var t_normal: texture_2d<f32>;
 @group(1) @binding(3)
 var t_rough: texture_2d<f32>;
 
+fn sky_aspect(look: vec3<f32>) -> vec4<f32> {
+    var pi = 3.14159;
+    let u_angle = atan2(look.x,look.z);
+    let u = (u_angle/pi) + 0.5; // from -pi/2 -> pi/2 into 0 -> 1
+    let v_angle = atan2(-look.y,sqrt(look.x * look.x + look.z * look.z));
+    let v = (v_angle/pi) + 0.5;//(v_angle/pi) + 0.5; // from -pi/2 -> pi/2 into 0 -> 1
+    let uv = vec2<f32>(u,v); // Get UV on skybox
+    return textureSample(sky_texture, sky_sampler, uv);
+}
+
+fn rotation(mat: mat4x4<f32>) -> mat3x3<f32> {
+    return mat3x3<f32>(
+        mat[0].xyz,
+        mat[1].xyz,
+        mat[2].xyz,
+    );
+}
+
+fn translation(mat: mat4x4<f32>) -> vec4<f32> {
+    //return vec4<f32>(mat[0][3],mat[1][3],mat[2][3],mat[3][3]);
+    return mat[3];
+}
+
 @fragment
 fn fs_main(in: VertexOutput) -> @location(0) vec4<f32> {
     let object_color: vec4<f32> = textureSample(t_diffuse, s_diffuse, in.tex_coords);
     let object_normal: vec4<f32> = textureSample(t_normal, s_diffuse, in.tex_coords);
 
-    let tangent_normal = object_normal.xyz * 2.0 - 1.0;
-    let light_dir = normalize(environment.dir.xyz);
-    let view_dir = normalize(view.frame[3].xyz - in.world_position);
-    let half_dir = normalize(view_dir + light_dir);
+    let diffuse_color = object_color.xyz;
+    let specular_color = vec3<f32>(0.0,0.0,0.0);
+    let reflection = sky_aspect(reflect(normalize(in.world_position-translation(eye.frame).xyz),normalize(in.world_normal)));
 
-    let diffuse_strength = max(dot(tangent_normal, light_dir), 0.0);
-    let diffuse_color = environment.light.xyz * diffuse_strength;
+    //let result = (environment.ambient.xyz + diffuse_color + specular_color) * object_color.xyz;
 
-    let specular_strength = pow(max(dot(tangent_normal, half_dir), 0.0), 32.0);
-    let specular_color = specular_strength * environment.light.xyz;
+    //let light_dir = normalize(environment.dir.xyz);
+    //let view_dir = normalize(eye.frame[3].xyz - in.world_position);
+    //let half_dir = normalize(view_dir + light_dir);
+
+    //let diffuse_strength = max(dot(tangent_normal, light_dir), 0.0);
+    //let diffuse_color = environment.light.xyz * diffuse_strength;
+
+    //let specular_strength = pow(max(dot(tangent_normal, half_dir), 0.0), 32.0);
+    //let specular_color = specular_strength * environment.light.xyz;
 
     let result = (environment.ambient.xyz + diffuse_color.xyz + specular_color.xyz) * object_color.xyz;
 
-    return vec4<f32>(result.xyz,object_color.a);
-}
+    return vec4<f32>(reflection.xyz,object_color.a);
+}
+
+struct SkyOutput {
+    @builtin(position) position: vec4<f32>,
+    @location(0) pos: vec4<f32> // unadulterated by WGSL
+}
+
+const TRI_VERTICES = array(
+    vec4(-1.0, -1.0, 1.0, 1.0),
+    vec4(-1.0,  1.0, 1.0, 1.0),
+    vec4( 1.0, -1.0, 1.0, 1.0),
+    vec4( 1.0,  1.0, 1.0, 1.0),
+    vec4(-1.0,  1.0, 1.0, 1.0),
+    vec4( 1.0, -1.0, 1.0, 1.0),
+);
+
+@vertex
+fn vs_sky(@builtin(vertex_index) index: u32) -> SkyOutput {
+    var out: SkyOutput;
+    out.position = TRI_VERTICES[index];
+    out.pos = out.position;
+    return out;
+}
+
+@fragment
+fn fs_sky(in: SkyOutput) -> @location(0) vec4<f32> {
+    let look = rotation(eye.frame) * in.pos.xyz;
+    return sky_aspect(look);
+}