struct fragment
{
	float4 position  : POSITION;	//screen position
	float4 color0    : COLOR0;
	float4 depthTexCoord: TEXCOORD0;
};


struct pixel
{
	float4 color : COLOR;	
};

pixel main(fragment IN, const uniform sampler2D depthMap)
{
	pixel OUT;
	OUT.color = IN.color0;
	
	// the depth buffer	has to be compared to the current depth
	float4 depth = tex2D(depthMap, IN.depthTexCoord.xy);
	float test = IN.depthTexCoord.z / IN.depthTexCoord.w;
	
	// reject by alpha test
	if (test < depth.x)
	{
		OUT.color.w = 0;
	//	OUT.color.y += 0.5;
	}
	
	return OUT;
}