struct VertexOut
{
	float4 VertexPosition		:POSITION;
	float2 TexCoord				:TEXCOORD;
	float4 Color1				:COLOR;	
};


/*
  Vertex program for displaying particle system with rectangle rendertexture 
*/
VertexOut VertexProgram( float4 Position :POSITION,
						float4 Texcoord: TEXCOORD,
						uniform float transparency,
						uniform float4x4 ModelViewProj	:state.matrix.mvp
						)									
{
	VertexOut Out;	
	
	Out.VertexPosition=mul(ModelViewProj, Position);
	Out.TexCoord=Texcoord.xy;	
	
	Out.Color1=float4(transparency,transparency,transparency,transparency);
	
	
	float z=(Out.VertexPosition.z/Out.VertexPosition.w+1)/2;
	
	float4 planes=float4(0.33,0.5,0.66,1);	
	if(z>planes.x)
	{
		Out.Color1.r=0;
	}
	if(z>planes.y)
	{
		Out.Color1.g=0;
	}
	if(z>planes.z)
	{
		Out.Color1.b=0;
	}
	
	return Out;	
}


/*
  Fragment program for displaying particle system with rectangle rendertexture
*/
void FragmentProgram(	VertexOut	In,
						uniform sampler2D Texture,
						uniform samplerRECT PhaseTexture,
						uniform float Albedo,
						uniform float Symmetry,
						out float4 Color:COLOR
						)
{
	
	float4 extintion=tex2D(Texture,In.TexCoord).r*In.Color1;	
	float scattered=Albedo*texRECT(PhaseTexture,float2(Symmetry,1)*256)/1.5;
	Color=1-extintion+extintion*scattered;	
	//Color=float4(0,0,0,0);	
}