Refactored compute ray tracing example, use dedicated graphics queue if available

data/shaders/raytracing/texture.vert

@@ -3,9 +3,6 @@
 #extension GL_ARB_separate_shader_objects : enable
 #extension GL_ARB_shading_language_420pack : enable
 
-layout (location = 0) in vec3 inPos;
-layout (location = 1) in vec2 inUV;
-
 layout (location = 0) out vec2 outUV;
 
 out gl_PerVertex 
@@ -15,6 +12,6 @@ out gl_PerVertex
 
 void main() 
 {
-	outUV = inUV;
-	gl_Position = vec4(inPos.xyz, 1.0);
+	outUV = vec2((gl_VertexIndex << 1) & 2, gl_VertexIndex & 2);
+	gl_Position = vec4(outUV * 2.0f + -1.0f, 0.0f, 1.0f);
 }