Vulcan Nightmare

Experimentally bringing up vulcan support

assets/shaders/skybox.frag.glsl

@@ -0,0 +1,34 @@
+#version 450
+
+layout(set = 0, binding = 0) uniform PerFrame {
+    mat4 view;
+    mat4 projection;
+    mat4 lightSpaceMatrix;
+    vec4 lightDir;
+    vec4 lightColor;
+    vec4 ambientColor;
+    vec4 viewPos;
+    vec4 fogColor;
+    vec4 fogParams;
+    vec4 shadowParams;
+};
+
+layout(push_constant) uniform Push {
+    vec4 horizonColor;
+    vec4 zenithColor;
+    float timeOfDay;
+} push;
+
+layout(location = 0) in vec3 WorldPos;
+layout(location = 1) in float Altitude;
+
+layout(location = 0) out vec4 outColor;
+
+void main() {
+    float t = clamp(Altitude, 0.0, 1.0);
+    t = pow(t, 1.5);
+    vec3 sky = mix(push.horizonColor.rgb, push.zenithColor.rgb, t);
+    float scatter = max(0.0, 1.0 - t * 2.0) * 0.15;
+    sky += vec3(scatter * 0.8, scatter * 0.4, scatter * 0.1);
+    outColor = vec4(sky, 1.0);
+}