//-------------------------------------------------------------------
// GLOBAL VARIABLES

float4x4 WorldViewProj : WorldViewProj;
float3   LightVector;                       //in object space; must be normalized
float    Ambient; 

texture  TextureMap;





sampler TextureMapSampler = sampler_state 
{
    Texture   = <TextureMap>;
    MinFilter = LINEAR;
    MagFilter = LINEAR;
    MipFilter = LINEAR;
    AddressU  = WRAP;
    AddressV  = WRAP;
};


//-------------------------------------------------------------------
// I/O STRUCTURES

struct VS_INPUT {
    float4 Position : POSITION; //in object space
    float3 Normal   : NORMAL;   //in object space
    float2 TexCoord : TEXCOORD0;
};

struct VS_OUTPUT_DIFFUSE {
    float4 Position    : POSITION; //in projection space
    float2 TexCoord0   : TEXCOORD0;
    float3 Normal      : TEXCOORD2;   //in tangent space
    float3 LightVector : TEXCOORD3;   //in tangent space
};
//-------------------------------------------------------------------
// VERTEX SHADERS


VS_OUTPUT_DIFFUSE Simple_VS(VS_INPUT IN)
{
    VS_OUTPUT_DIFFUSE OUT;

    // pass texture coordinates for fetching the diffuse map
    OUT.TexCoord0 = IN.TexCoord.xy;
    // transform position to projection space
    OUT.Position = mul(IN.Position, WorldViewProj);
		OUT.LightVector = float3(-0.707,0.707,0.0);
		OUT.Normal = IN.Normal;
		
    return OUT;
}

float4 Simple_PS(VS_OUTPUT_DIFFUSE IN) : COLOR
{
    //fetch base color
    float4 color = tex2D(TextureMapSampler, IN.TexCoord0.xy);
    
    //compute self-shadowing term
    float shadow = saturate(4 * dot(IN.Normal.xyz ,  IN.LightVector.xyz ));
    
    //compute final color
    return color* shadow;
}



Technique Simple
{
    Pass P0
    {
        VertexShader = compile vs_1_1 Simple_VS();
        PixelShader  = compile ps_1_1 Simple_PS();
        
        AlphaBlendEnable = False;
    }
}