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


/*
  Vertex program for cloud rendering 
*/
VertexOut VertexProgram( float4 Position :POSITION,
						float2 Texcoord: TEXCOORD
						)									
{
	VertexOut Out;	
	
	Out.VertexPosition=Position;
	Out.TexCoord=Texcoord;
	
	return Out;	
}

/*
  Fragment program for cloud rendering 
*/
float4 FragmentProgram(	VertexOut	In,
						uniform float Albedo,
						uniform float Transparency,
						uniform float Symmetry,
						uniform samplerRECT IllumTexture,
						uniform samplerRECT PhaseTexture,
						uniform samplerRECT AngleTexture):COLOR
{
	In.TexCoord.y=1-In.TexCoord.y;
	float uvsize=256;	
	float4 Color=texRECT(IllumTexture,In.TexCoord*uvsize);
	
	if(Color.a!=1)
	{
		
		//3 random uv's	
		float transparency=Transparency;
		float albedo=Albedo;
		float t=0.3;
		float g=Symmetry;
		
		float2 Rand1=(float2(noise(float3(In.TexCoord,t)),noise(float3(In.TexCoord.x,t,In.TexCoord.y))))*10;
		float2 Rand2=(float2(noise(float3(In.TexCoord.yx,t)),noise(float3(In.TexCoord.y,t,In.TexCoord.x))))*10;
		float2 Rand3=(float2(noise(float3(t,In.TexCoord)),noise(float3(t,In.TexCoord.yx))))*10;
		
		float3 dist;
		float3 Cosangles;
		float3 PhasesFront;
		float3 PhasesBack;
		float3 Scattering;
		
		float3 RedSamples;
		float3 GreenSamples;
		float3 BlueSamples;
		float3 AlphaSamples;
		
		/*
		float2 point1=saturate(In.TexCoord+Rand1)*uvsize;	
		float2 point2=saturate(In.TexCoord+Rand2)*uvsize;
		float2 point3=saturate(In.TexCoord+Rand3)*uvsize;
		
		RedSamples=float3(texRECT(IllumTexture,point1).r,texRECT(IllumTexture,point2).r,texRECT(IllumTexture,point3).r);
		GreenSamples=float3(texRECT(IllumTexture,point1).g,texRECT(IllumTexture,point2).g,texRECT(IllumTexture,point3).g);
		BlueSamples=float3(texRECT(IllumTexture,point1).b,texRECT(IllumTexture,point2).b,texRECT(IllumTexture,point3).b);
		AlphaSamples=float3(texRECT(IllumTexture,point1).a,texRECT(IllumTexture,point2).a,texRECT(IllumTexture,point3).a);
		*/
		
		In.TexCoord*=uvsize;
		
		RedSamples=float3(texRECT(IllumTexture,In.TexCoord+Rand1).r,texRECT(IllumTexture,In.TexCoord+Rand2).r,texRECT(IllumTexture,In.TexCoord+Rand3).r);
		GreenSamples=float3(texRECT(IllumTexture,In.TexCoord+Rand1).g,texRECT(IllumTexture,In.TexCoord+Rand2).g,texRECT(IllumTexture,In.TexCoord+Rand3).g);
		BlueSamples=float3(texRECT(IllumTexture,In.TexCoord+Rand1).b,texRECT(IllumTexture,In.TexCoord+Rand2).b,texRECT(IllumTexture,In.TexCoord+Rand3).b);
		AlphaSamples=float3(texRECT(IllumTexture,In.TexCoord+Rand1).a,texRECT(IllumTexture,In.TexCoord+Rand2).a,texRECT(IllumTexture,In.TexCoord+Rand3).a);
		
		/*	
		//background	
		if(RedSamples.x==1)RedSamples.x=0;
		if(RedSamples.y==1)RedSamples.y=0;
		if(RedSamples.z==1)RedSamples.z=0;
		if(GreenSamples.x==1)GreenSamples.x=0;
		if(GreenSamples.y==1)GreenSamples.y=0;
		if(GreenSamples.z==1)GreenSamples.z=0;
		if(BlueSamples.x==1)BlueSamples.x=0;
		if(BlueSamples.y==1)BlueSamples.y=0;
		if(BlueSamples.z==1)BlueSamples.z=0;
		*/
		
		dist=float3(length(Rand1),length(Rand2),length(Rand3));
		
		Cosangles=float3(texRECT(AngleTexture,float2(dist.x,0.25)).r,
						texRECT(AngleTexture,float2(dist.y,0.25)).r,
						texRECT(AngleTexture,float2(dist.z,0.25)).r)/2;
			
		PhasesFront=float3(texRECT(PhaseTexture,float2(g,0.5+Cosangles.x)*256).r,
					texRECT(PhaseTexture,float2(g,0.5+Cosangles.y)*256).r,
					texRECT(PhaseTexture,float2(g,0.5+Cosangles.z)*256).r);
		PhasesBack=float3(texRECT(PhaseTexture,float2(g,0.5-Cosangles.x)*256).r,
					texRECT(PhaseTexture,float2(g,0.5-Cosangles.y)*256).r,
					texRECT(PhaseTexture,float2(g,0.5-Cosangles.z)*256).r);
		
		PhasesFront*=transparency*albedo/12.5;
		PhasesBack*=transparency*albedo/12.5;
		
		//Red Channel
		//Scattering=Color.g*PhasesBack;	
		Scattering=GreenSamples*PhasesBack;	
		Color.r+=Scattering.x+Scattering.y+Scattering.z;
		
		//Green Channel
		//Scattering=Color.b*PhasesBack+Color.r*PhasesFront;
		Scattering=RedSamples*PhasesFront+BlueSamples*PhasesBack;	
		Color.g+=Scattering.x+Scattering.y+Scattering.z;
		
		//Blue Channel
		//Scattering=Color.a*PhasesBack+Color.g*PhasesFront;
		Scattering=GreenSamples*PhasesFront+AlphaSamples*PhasesBack;	
		Color.b+=Scattering.x+Scattering.y+Scattering.z;
		
		//Alpha Channel
		//Scattering=Color.b*PhasesFront;
		Scattering=BlueSamples*PhasesFront;	
		Color.a+=Scattering.x+Scattering.y+Scattering.z;
						
	}
	else
	{
		Color=float4(1,1,1,1);
	}
	
	return Color;
}