///////////////////////////////////////////////////////////////////////////////
//
//      ##  ######
//       ######  ###
//  ## ###############        Shark 3D Engine (www.shark3d.com)
//   ########## # # #
//    ########                Copyright (c) 1996-2006 Spinor GmbH.
//   ######### # # #          All rights reserved.
//  ##   ##########
//      ##
//
///////////////////////////////////////////////////////////////////////////////

struct VS_INPUT
{
    float4 posObj: POSITION;
    float2 mainTexCoord: TEXCOORD0;
};

struct VS_OUTPUT
{
    float4 posScr: POSITION;
    float fog: FOG;
    float4 diffuse: COLOR0;
    float2 mainTexCoord: TEXCOORD0;
    float4 baseVec: TEXCOORD2;
};

///////////////////////////////////////////////////////////////////////////////

const float4x4 matProjView;
const float4x4 matView;
const float4 mtrlEmissive;

const float4 passInfo;
const float4 tex0RcpSize;

///////////////////////////////////////////////////////////////////////////////
// Vertexshader
// Profile: 1x1

VS_OUTPUT main( VS_INPUT input )
{
    VS_OUTPUT output = (VS_OUTPUT)0;

    //Transform position to clip space
    output.posScr = mul(input.posObj, matProjView);

    //Transform position to eye space -> pos
    float4 posView = mul(input.posObj, matView);

    //fog
    output.fog = posView.z / posView.w;

    //Color
    output.diffuse = mtrlEmissive;

    // Texture coordinates
    output.mainTexCoord = input.mainTexCoord;

    // Scaling offset
    int iter = passInfo.x;

    float2 offsScale = tex0RcpSize * pow(2, iter) * 0.5;

    float4 dirVec;
    int fiter = fmod(iter, 4.0);
    if(fiter < 2.0)
    {
        if(fiter < 1.0)
            dirVec = float4(1, 0, 0, 1); // Vectors (1, 0) and (0, 1)
        else
            dirVec = float4(1, 1,-1, 1); // Vectors (1, 1) and (-1, 1)
    }
    else
    {
        if(fiter < 3.0)
            dirVec = float4(2, 1,-1, 2); // Vectors (2, 1) and (-1, 2)
        else
            dirVec = float4(1, 2,-2, 1); // Vectors (1, 2) and (-2, 1)
    }
    
    output.baseVec = dirVec * offsScale.xyxy;

    return output;
}

///////////////////////////////////////////////////////////////////////////////