Parameters =
{
	float3 		gViewDir : auto("ViewDir");
	float3 		gViewOrigin : auto("ViewOrigin");
	mat4x4		gMatViewProj : auto("VP");	
	mat4x4		gMatView : auto("V");
	mat4x4		gMatProj : auto("P");
	mat4x4		gMatInvProj : auto("IP");
	mat4x4		gMatInvViewProj : auto("IVP");
	
	// Special inverse view-projection matrix that had projection entries that affect z and w eliminated.
	// Used to transform a vector(clip_x, clip_y, view_z, view_w), where clip_x/clip_y are in clip space, 
	// and view_z/view_w in view space, into world space
	mat4x4      gMatScreenToWorld : auto("ScreenToWorld");
	
	// Converts device Z to world Z using this formula: worldZ = (1 / (deviceZ + y)) * x
	float2		gDeviceZToWorldZ : auto("DeviceToWorldZ");
	
	// x - near plane distance, y - far plane distance
	float2		gNearFar : auto("NearFar");
	
	// xy - Viewport offset in pixels
	// zw - Viewport width & height in pixels
	int4 		gViewportRectangle : auto("ViewportRect");
	
	// xy - (Viewport size in pixels / 2) / Target size in pixels
	// zw - (Viewport offset in pixels + (Viewport size in pixels / 2) + Optional pixel center offset) / Target size in pixels	
	float4 		gClipToUVScaleOffset : auto("ClipToUVScaleOffset");	

	float		gAmbientFactor;
};

Blocks =
{
	Block PerCamera : auto("PerCamera");
};

Technique : base("PerCameraData") =
{
	Pass =
	{
		Common = 
		{
			cbuffer PerCamera
			{
				float3	 gViewDir;
				float3 	 gViewOrigin;
				float4x4 gMatViewProj;
				float4x4 gMatView;
				float4x4 gMatProj;
				float4x4 gMatInvProj;
				float4x4 gMatInvViewProj;
				float4x4 gMatScreenToWorld;
				float2 	 gDeviceZToWorldZ;
				float2	 gNDCZToWorldZ;
				float2	 gNearFar;
				int4 	 gViewportRectangle;
				float4 	 gClipToUVScaleOffset;	
				float	gAmbientFactor;
			}
			
			/** Converts Z value in range [0,1] into Z value in view space. */
			float convertFromDeviceZ(float deviceZ)
			{
				return (1.0f / (deviceZ + gDeviceZToWorldZ.y)) * gDeviceZToWorldZ.x;
			}
			
			/** Converts Z value from view space to NDC space. */
			float convertToNDCZ(float viewZ)
			{
				return -gNDCZToWorldZ.y + (gNDCZToWorldZ.x / viewZ);
			}
		};
	};
};