Clean up sky shaders and extra push constant data

engine/renderer/src/renderer.cpp

@@ -480,16 +480,16 @@ void Renderer::render_camera(GFXCommandBuffer* command_buffer, Scene& scene, Obj
     
     struct SkyPushConstant {
         Matrix4x4 view;
-        Vector4 aspectFovY;
-        Vector4 sunPosition;
+        Vector4 sun_position_fov;
+        float aspect;
     } pc;
     
     pc.view = matrix_from_quat(scene.get<Transform>(camera_object).rotation) * correction_matrix;
-    pc.aspectFovY = Vector4(static_cast<float>(extent.width) / static_cast<float>(extent.height), radians(camera.fov), 0, 0);
+    pc.aspect = static_cast<float>(extent.width) / static_cast<float>(extent.height);
     
     for(const auto& [obj, light] : scene.get_all<Light>()) {
         if(light.type == Light::Type::Sun)
-            pc.sunPosition = Vector4(scene.get<Transform>(obj).get_world_position());
+            pc.sun_position_fov = Vector4(scene.get<Transform>(obj).get_world_position(), radians(camera.fov));
     }
     
     command_buffer->set_pipeline(skyPipeline);
@@ -887,7 +887,7 @@ void Renderer::createSkyPipeline() {
     };
 
     pipelineInfo.shader_input.push_constants = {
-        {sizeof(Matrix4x4) + sizeof(Vector4) + sizeof(Vector4), 0}
+        {sizeof(Matrix4x4) + sizeof(Vector4) + sizeof(float), 0}
     };
 
     pipelineInfo.depth.depth_mode = GFXDepthMode::LessOrEqual;

engine/renderer/src/scenecapture.cpp

@@ -281,17 +281,17 @@ void SceneCapture::render(GFXCommandBuffer* command_buffer, Scene* scene) {
                 // render sky
                 struct SkyPushConstant {
                     Matrix4x4 view;
-                    Vector4 aspectFovY;
-                    Vector4 sunPosition;
+                    Vector4 sun_position_fov;
+                    float aspect;
                 } pc;
                 
                 pc.view = sceneTransforms[face];
                 pc.view[3] = Vector4(0, 0, 0, 1); // zero out translation
-                pc.aspectFovY = Vector4(1.0f, radians(90.0f), 0, 0);
+                pc.aspect = 1.0f;
                 
                 for(auto& [obj, light] : scene->get_all<Light>()) {
                     if(light.type == Light::Type::Sun)
-                        pc.sunPosition = Vector4(scene->get<Transform>(obj).get_world_position());
+                        pc.sun_position_fov = Vector4(scene->get<Transform>(obj).get_world_position(), radians(90.0f));
                 }
                 
                 command_buffer->set_pipeline(skyPipeline);
@@ -404,7 +404,7 @@ void SceneCapture::createSkyResources() {
     };
     
     pipelineInfo.shader_input.push_constants = {
-        {sizeof(Matrix4x4) + sizeof(Vector4) + sizeof(Vector4), 0}
+        {sizeof(Matrix4x4) + sizeof(Vector4) + sizeof(float), 0}
     };
     
     pipelineInfo.depth.depth_mode = GFXDepthMode::LessOrEqual;

shaders/sky.frag.glsl

@@ -1,42 +1,48 @@
-#extension GL_GOOGLE_include_directive : enable
-
 #include "atmosphere.glsl"
 
-layout (location = 0) in vec2 inUV;
+layout (location = 0) in vec2 in_uv;
 
-layout (location = 0) out vec4 outColor;
+layout (location = 0) out vec4 out_color;
 
 layout(push_constant, binding = 1) uniform PushConstant{
     mat4 view;
-    vec4 aspectFovY, sunPosition;
+    vec4 sun_position_fov;
+    float aspect;
 };
 
-vec3 skyRay (vec2 Texcoord) {
-    float d = 0.5 / tan(aspectFovY.y/2.0);
-    return normalize(vec3((Texcoord.x - 0.5) * aspectFovY.x,
-                           Texcoord.y - 0.5,
+vec3 sky_ray(const vec2 uv) {
+    const float d = 0.5 / tan(sun_position_fov.w / 2.0);
+    return normalize(vec3((uv.x - 0.5) * aspect,
+                           uv.y - 0.5,
                            -d));
 }
 
 void main() {
-    vec3 vPosition = mat3(view) * skyRay(inUV);
-
-    vec3 color = atmosphere(
-        normalize(vPosition),           // normalized ray direction
-        vec3(0,6372e3,0),               // ray origin
-        sunPosition.xyz,                        // position of the sun
-        22.0,                           // intensity of the sun
-        6371e3,                         // radius of the planet in meters
-        6471e3,                         // radius of the atmosphere in meters
-        vec3(5.5e-6, 13.0e-6, 22.4e-6), // Rayleigh scattering coefficient
-        21e-6,                          // Mie scattering coefficient
-        8e3,                            // Rayleigh scale height
-        1.2e3,                          // Mie scale height
-        0.758                           // Mie preferred scattering direction
+    const vec3 color = atmosphere(
+        // ray direction
+        normalize(mat3(view) * sky_ray(in_uv)),
+        // ray origin
+        vec3(0, 6372e3, 0),
+        // position of the sun in world space (this will be normalized)
+        sun_position_fov.xyz,
+        // intensity of the sun
+        22.0,
+        // radius of the plant in meters
+        6371e3,
+        // radius of the atmosphere in meters
+        6471e3,
+        // Rayleigh scattering coefficient
+        vec3(5.5e-6, 13.0e-6, 22.4e-6),
+        // Mie scattering coefficient
+        21e-6,
+        // Rayleigh scale height
+        8e3,
+        // Mie scale height
+        1.2e3,
+        // Mie preferred scattering direction
+        0.758
     );
 
-    // Apply exposure.
-    color = 1.0 - exp(-1.0 * color);
-
-    outColor = vec4(color, 1);
+    // apply exposure
+    out_color = vec4(1.0 - exp(-1.0 * color), 1.0);
 }

shaders/sky.vert.glsl

@@ -1,6 +1,6 @@
-layout (location = 0) out vec2 outUV;
+layout (location = 0) out vec2 out_uv;
 
 void main() {
-    outUV = vec2((gl_VertexIndex << 1) & 2, gl_VertexIndex & 2);
-    gl_Position = vec4(outUV * 2.0f + -1.0f, 1.0f, 1.0f);
+    out_uv = vec2((gl_VertexIndex << 1) & 2, gl_VertexIndex & 2);
+    gl_Position = vec4(out_uv * 2.0f + -1.0f, 1.0f, 1.0f);
 }