struct VertexOut
{
	float4 VertexPosition		:POSITION;
	float2 TexCoord				:TEXCOORD;
	float3 Position				:TEXCOORD1;
	float ID					:TEXCOORD2;
};


/*
  Vertex program for cloud rendering 
*/
VertexOut VertexProgram( float4 Position :POSITION,
						float ID: TEXCOORD,
						uniform float WindowSize,
						uniform float4x4 ModelViewProj	:state.matrix.mvp
						)									
{
	VertexOut Out;	
	
	Out.VertexPosition=mul(ModelViewProj, Position);
	
	Out.ID=ID;
	
	Out.Position=Out.VertexPosition.xyz/2+0.5;
	Out.Position.xy*=WindowSize;
	
	return Out;	
}

/*
  Fragment program for cloud rendering 
*/
void FragmentProgram(	VertexOut	In,
						uniform samplerRECT PrevFrame,
						out float4 Color:COLOR,
						uniform float peel
						//,out float Depth:DEPTH
						)
{	
	float z0=texRECT(PrevFrame,In.Position.xy).g;	
	Color=float4(1,In.Position.z,0,1);	
	
	if(In.Position.z<=peel)
	{
		Color.a=0;
	}		
	
}