prototype for spirv linking

funnyassets/shaders/funny_basic_pbr.shader

@@ -2,13 +2,18 @@
 
 COMMON
 {
-
+	struct RayPayload
+	{
+		float3 m_vOrigin;
+		float3 m_vDirection;
+		float3 m_vColor;
+	};
 }
 CALLABLE
 {
 	#include "textures.hlsl"
-	float4 brdfMain()
+	void brdfMain( inout RayPayload payload )
 	{
-		return float4(1);
+		payload.m_vColor = float3(1.0,0.0,1.0);
 	}
 }