/* -*- mode: c++; c-basic-offset: 4; indent-tabs-mode: nil -*- */
/*
 * ======================================================================
 *  AUTHOR:  Wei Qiao <qiaow@purdue.edu>
 *           Purdue Rendering and Perceptualization Lab (PURPL)
 *
 *  Copyright (c) 2004-2012  HUBzero Foundation, LLC
 *
 *  See the file "license.terms" for information on usage and
 *  redistribution of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 * ======================================================================
 */

#include "common.cg"
 
v2f main(a2v IN,
         uniform float4x4 modelViewProjMatrix,
         uniform float4x4 modelViewInv)
{
    v2f OUT;

    // IN.Position is in eye coords
    float4 objPos = mul(modelViewInv, IN.Position);
    float4 eyePosObjSpace = mul(modelViewInv, float4(0,0,0,1));

    //clip space vertex position
    //OUT.HPosition = mul(modelViewProjMatrix, mul(modelViewInv, IN.Position));
    OUT.HPosition = mul(modelViewProjMatrix, objPos);

    //eye space texture coordinates
    OUT.TexCoord = IN.TexCoord;

    //world space eye position
    //OUT.EyeVector = normalize(-IN.Position.xyz);
    OUT.EyeVector = normalize(eyePosObjSpace - objPos);

    //world space light postion
    //OUT.Light = normalize(float3(1,1,1)-IN.Position.xyz);
    OUT.Light = normalize(mul(modelViewInv, float4(1,1,1,1))-objPos);

    return OUT;
}