source/renderer/MikktspaceWrap.h

   1 /* Copyright (C) 2012 Wildfire Games.
   2  * This file is part of 0 A.D.
   3  *
   4  * 0 A.D. is free software: you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation, either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * 0 A.D. is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with 0 A.D.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 #ifndef INCLUDED_MIKKWRAP
  19 #define INCLUDED_MIKKWRAP
  20
  21
  22 #include "third_party/mikktspace/mikktspace.h"
  23
  24 class MikkTSpace
  25 {
  26
  27 public:
  28
  29         MikkTSpace(const CModelDefPtr& m, std::vector<float>& v, bool gpuSkinning);
  30
  31         void generate();
  32
  33 private:
  34
  35         SMikkTSpaceInterface m_Interface;
  36         SMikkTSpaceContext m_Context;
  37
  38         const CModelDefPtr& m_Model;
  39
  40         std::vector<float>& m_NewVertices;
  41         bool m_GpuSkinning;
  42
  43
  44         // Returns the number of faces (triangles/quads) on the mesh to be processed.
  45         static int getNumFaces(const SMikkTSpaceContext *pContext);
  46
  47
  48         // Returns the number of vertices on face number iFace
  49         // iFace is a number in the range {0, 1, ..., getNumFaces()-1}
  50         static int getNumVerticesOfFace(const SMikkTSpaceContext *pContext, const int iFace);
  51
  52
  53         // returns the position/normal/texcoord of the referenced face of vertex number iVert.
  54         // iVert is in the range {0,1,2} for triangles and {0,1,2,3} for quads.
  55         static void getPosition(const SMikkTSpaceContext *pContext,
  56                         float fvPosOut[], const int iFace, const int iVert);
  57
  58         static void getNormal(const SMikkTSpaceContext *pContext,
  59                         float fvNormOut[], const int iFace, const int iVert);
  60
  61         static void getTexCoord(const SMikkTSpaceContext *pContext,
  62                         float fvTexcOut[], const int iFace, const int iVert);
  63
  64
  65         // This function is used to return tangent space results to the application.
  66         // fvTangent and fvBiTangent are unit length vectors and fMagS and fMagT are their
  67         // true magnitudes which can be used for relief mapping effects.
  68         // fvBiTangent is the "real" bitangent and thus may not be perpendicular to fvTangent.
  69         // However, both are perpendicular to the vertex normal.
  70         // For normal maps it is sufficient to use the following simplified version of the bitangent which is generated at pixel/vertex level.
  71         // fSign = bIsOrientationPreserving ? 1.0f : (-1.0f);
  72         // bitangent = fSign * cross(vN, tangent);
  73         static void setTSpace(const SMikkTSpaceContext * pContext, const float fvTangent[],
  74                         const float fvBiTangent[], const float fMagS, const float fMagT,
  75                         const tbool bIsOrientationPreserving, const int iFace, const int iVert);
  76
  77
  78 };
  79
  80
  81 #endif // INCLUDED_MIKKWRAP