surfacegeometry.h

/*
    Lightmetrica : A research-oriented renderer

    Copyright (c) 2014 Hisanari Otsu

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#pragma once
#ifndef __LIB_LIGHTMETICA_SURFACE_GEOMETRY_H__
#define __LIB_LIGHTMETICA_SURFACE_GEOMETRY_H__

#include "common.h"
#include "math.types.h"
#include "math.linalgebra.h"

LM_NAMESPACE_BEGIN

struct SurfaceGeometry
{

    bool degenerated;               

    Math::Vec3 p;                   
    Math::Vec3 gn;                  
    Math::Vec3 sn;                  
    Math::Vec3 ss, st;              
    Math::Vec2 uv;                  

    Math::Mat3 worldToShading;      
    Math::Mat3 shadingToWorld;      

    LM_FORCE_INLINE void ComputeTangentSpace()
    {
        // Tangent vectors
        Math::OrthonormalBasis(sn, ss, st);

        // Shading coordinates conversion
        shadingToWorld = Math::Mat3(ss, st, sn);
        worldToShading = Math::Transpose(shadingToWorld);
    }

};

LM_NAMESPACE_END

#endif // __LIB_LIGHTMETICA_SURFACE_GEOMETRY_H__