// DEFINES IN CASE WE USE GL OR DX
#if OPENGL
    #define VS_SHADERMODEL vs_3_0
    #define PS_SHADERMODEL ps_3_0
#else
    #define VS_SHADERMODEL vs_4_0_level_9_1
    #define PS_SHADERMODEL ps_4_0_level_9_1
#endif


// DEFINE GLOBAL VARIABLES BELOW
matrix World;
matrix View;
matrix Projection;

matrix LightView;
matrix LightProjection;

float1 MaxClippingDistance;

Texture2D ShadowMap;

sampler2D ShadowMapSampler = sampler_state
{
    texture = <ShadowMap>;
    magfilter = LINEAR;
    minfilter = LINEAR;
    mipfilter = LINEAR;
    AddressU = clamp;
    AddressV = clamp;
};


///
/// SHADOW MAP METHODS
///

// VECTOR SHADER INPUT
struct VS_Map_Input
{
    float4 Position : SV_POSITION;
};

// VECTOR SHADER OUTPUT / PIXEL SHADER INPUT
struct VS_Map_Output
{
    float4 position : SV_POSITION;
    float4 position2D : TEXCOORD0;
};

// VECTOR SHADER METHOD
VS_Map_Output VSShadowMap(in VS_Map_Input input)
{
    VS_Map_Output output;

    output.position = mul(input.Position, World);
    output.position = mul(output.position, LightView);
    output.position = mul(output.position, LightProjection);
    output.position2D = output.position;

    return output;
}

// PIXEL SHADER METHOD
float4 PSShadowMap(VS_Map_Output input) : COLOR
{
    float4 temp = saturate(input.position2D.z / (input.position2D.w));
    temp.w = 1.0f;  // set visibility to 100%
    return temp;
}

///
/// SHADOW SCENE METHODS
///

struct VS_Scene_Input
{
    float4 Position : SV_POSITION;
    float4 Normal : NORMAL;
};

struct VS_Scene_Output
{
    float4 position : SV_POSITION;
    float4 lightPosition : TEXCOORD0;
    float4 position2D : TEXCOORD1;
};

// VECTOR SHADER METHOD
VS_Scene_Output VSShadowScene(in VS_Scene_Input input)
{
    VS_Scene_Output output;

    output.position = mul(input.Position, World);
    output.position = mul(output.position, View);
    output.position = mul(output.position, Projection);
    output.position2D = output.position;

    output.lightPosition = mul(input.Position, World);
    output.lightPosition = mul(output.lightPosition, LightView);
    output.lightPosition = mul(output.lightPosition, LightProjection);

    return output;
}

float4 PSShadowScene(VS_Scene_Output input) : COLOR
{
    float visibility = 1.0f;

    float depth = input.position2D.z / input.position2D.w;
    float shadowDepth = tex2D(ShadowMapSampler, input.lightPosition.xy).z;

    //if (depth > shadowDepth)
    //{
    //    return float4(1, 0, 0, 1);

    //}

    //return float4(0, 1, 1, 1);

    return tex2D(ShadowMapSampler, input.lightPosition.xy);

}


// DON'T CHANGE ANYTHING BELOW HERE!
technique GenerateShadowMap
{
    pass Pass0
    {
        VertexShader = compile VS_SHADERMODEL VSShadowMap();
        PixelShader = compile PS_SHADERMODEL PSShadowMap();
    }
}

technique ShadowScene
{
    pass Pass0
    {
        VertexShader = compile VS_SHADERMODEL VSShadowScene();
        PixelShader = compile PS_SHADERMODEL PSShadowScene();
    }
}

// EOF MARKER