source/mupen64plus-video-arachnoid/src/Combiner/SimpleTexEnvCombiner.cpp

   1 /******************************************************************************
   2  * Arachnoid Graphics Plugin for Mupen64Plus
   3  * http://bitbucket.org/wahrhaft/mupen64plus-video-arachnoid/
   4  *
   5  * Copyright (C) 2007 Kristofer Karlsson, Rickard Niklasson
   6  *
   7  * This program is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU General Public License
   9  * as published by the Free Software Foundation; either version 2
  10  * of the License, or (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  20  *****************************************************************************/
  21
  22 #include "SimpleTexEnvCombiner.h"
  23 #include "CombinerStructs.h"
  24 #include "MultiTexturingExt.h"
  25 #include "ExtensionChecker.h"
  26 #include "m64p.h"
  27 #include "OpenGL.h"
  28
  29 //-----------------------------------------------------------------------------
  30 //! Constructor
  31 //-----------------------------------------------------------------------------
  32 SimpleTexEnvCombiner::SimpleTexEnvCombiner()
  33 {
  34 }
  35
  36 //-----------------------------------------------------------------------------
  37 //! Destructor
  38 //-----------------------------------------------------------------------------
  39 SimpleTexEnvCombiner::~SimpleTexEnvCombiner()
  40 {
  41 }
  42
  43 //-----------------------------------------------------------------------------
  44 //* Initialize
  45 //! Checks if multitexturing is supported
  46 //-----------------------------------------------------------------------------
  47 void SimpleTexEnvCombiner::initialize()
  48 {
  49     ARB_multitexture = isExtensionSupported("GL_ARB_multitexture");
  50 }
  51
  52 //-----------------------------------------------------------------------------
  53 //* Begin Texture Update
  54 //! Called before texture channels are updated on the RDP
  55 //-----------------------------------------------------------------------------
  56 void SimpleTexEnvCombiner::beginTextureUpdate()
  57 {
  58     //Ignore?
  59 }
  60
  61 //-----------------------------------------------------------------------------
  62 //* End Texture Update
  63 //! Called after texture channels are updated on the RDP
  64 //! @param[in] texEnv Texture Environment
  65 //-----------------------------------------------------------------------------
  66 void SimpleTexEnvCombiner::endTextureUpdate(TexEnvCombiner* texEnv)
  67 {
  68     //Ignore
  69 }
  70
  71 //-----------------------------------------------------------------------------
  72 //! Set Texture Envirorment Colors
  73 //! @param[in] texEnv Texture Environment
  74 //-----------------------------------------------------------------------------
  75 void SimpleTexEnvCombiner::setTextureEnviromentColors(TexEnvCombiner* texEnv)
  76 {
  77     //Ignore
  78 }
  79
  80 //-----------------------------------------------------------------------------
  81 //* Set Texture Environment
  82 //! Enables texturing and sets texture environment in OpenGL
  83 //! @param[in] texEnv Texture Environment
  84 //-----------------------------------------------------------------------------
  85 void SimpleTexEnvCombiner::setTextureEnviroment(TexEnvCombiner* texEnv)
  86 {
  87     if ( ARB_multitexture )
  88         glActiveTextureARB( GL_TEXTURE0_ARB );
  89
  90     if (texEnv->usesT0 || texEnv->usesT1)
  91         glEnable( GL_TEXTURE_2D );
  92     else
  93         glDisable( GL_TEXTURE_2D );
  94
  95     //Set Mode
  96     glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, texEnv->mode);
  97 }
  98
  99 //-----------------------------------------------------------------------------
 100 //* Create New Texture Enviornment
 101 //! Allocates a new texture enviroment
 102 //! @param[in] colorCombiner How to combine and get a color
 103 //! @param[in] alphaCombiner How to combine and get an alpha value
 104 //! @return The texture enviroment that was created
 105 //-----------------------------------------------------------------------------
 106 TexEnvCombiner* SimpleTexEnvCombiner::createNewTextureEnviroment(Combiner* colorCombiner, Combiner *alphaCombiner)
 107 {
 108     TexEnvCombiner* texEnv = new TexEnvCombiner();
 109
 110     bool m_usesTexture0 = false;
 111     bool m_usesTexture1 = false;
 112     int mode = GL_REPLACE;
 113     unsigned short m_color = COMBINED;
 114     unsigned short m_alpha = COMBINED;
 115
 116     //For each stage in alpha combiner
 117     for (int i = 0; i < alphaCombiner->numStages; i++)
 118     {
 119         //For each operation in stage
 120         for (int j = 0; j < alphaCombiner->stage[i].numOps; j++)
 121         {
 122             CombinerOp* op = &alphaCombiner->stage[i].op[j];
 123
 124             //Apply operation
 125             switch ( alphaCombiner->stage[i].op[j].op )
 126             {
 127                 case LOAD:
 128                     if ( op->param1 != TEXEL0_ALPHA &&  op->param1 != TEXEL1_ALPHA  )
 129                     {
 130                         m_alpha = op->param1;
 131                         m_usesTexture0 = false;
 132                         m_usesTexture1 = false;
 133                     }
 134                     else
 135                     {
 136                         mode = GL_REPLACE;
 137                         m_usesTexture0 = op->param1 == TEXEL0_ALPHA;
 138                         m_usesTexture1 = op->param1 == TEXEL1_ALPHA;
 139                     }
 140                     break;
 141                 case MUL: {
 142                         CombinerOp* prevOp = &alphaCombiner->stage[i].op[j-1];
 143
 144                         if (((op->param1 == TEXEL0_ALPHA) || (op->param1 == TEXEL1_ALPHA)) &&
 145                             ((prevOp->param1 != TEXEL0_ALPHA) || (prevOp->param1 != TEXEL1_ALPHA)))
 146                         {
 147                             mode = GL_MODULATE;
 148                         }
 149                         else if ( ( op->param1 != TEXEL0_ALPHA || op->param1 != TEXEL1_ALPHA) &&
 150                                 (prevOp->param1 == TEXEL0_ALPHA || prevOp->param1 == TEXEL1_ALPHA) )
 151                         {
 152                             m_alpha = op->param1;
 153                             mode = GL_MODULATE;
 154                         }
 155                     }
 156                     break;
 157             }
 158         }
 159     }
 160
 161
 162     //For each stage in colorCombiner
 163     for (int i = 0; i < colorCombiner->numStages; i++)
 164     {
 165         for (int j = 0; j < colorCombiner->stage[i].numOps; j++)
 166         {
 167             CombinerOp* op = &colorCombiner->stage[i].op[j];
 168
 169             switch ( colorCombiner->stage[i].op[j].op )
 170             {
 171                 case LOAD:
 172                     if (op->param1 == TEXEL0 || op->param1 == TEXEL0_ALPHA)
 173                     {
 174                         if ( mode == GL_MODULATE )
 175                             m_color = ONE;
 176
 177                         m_usesTexture0 = true;
 178                         m_usesTexture1 = false;
 179                     }
 180                     else if ( op->param1 == TEXEL1 || op->param1 == TEXEL1_ALPHA )
 181                     {
 182                         if ( mode == GL_MODULATE )
 183                             m_color = ONE;
 184
 185                         m_usesTexture0 = false;
 186                         m_usesTexture1 = true;
 187                     }
 188                     else
 189                     {
 190                         m_color = op->param1;
 191                         m_usesTexture0 = m_usesTexture1 = false;
 192                     }
 193                     break;
 194                 case MUL:
 195                     if ( op->param1 == TEXEL0 || op->param1 == TEXEL0_ALPHA )
 196                     {
 197                         if (!m_usesTexture0 && !m_usesTexture1)
 198                         {
 199                             mode = GL_MODULATE;
 200                             m_usesTexture0 = true;
 201                             m_usesTexture1 = false;
 202                         }
 203                     }
 204                     else if ( op->param1 == TEXEL1 || op->param1 == TEXEL1_ALPHA )
 205                     {
 206                         if (!m_usesTexture0 && !m_usesTexture1)
 207                         {
 208                             mode = GL_MODULATE;
 209                             m_usesTexture0 = false;
 210                             m_usesTexture1 = true;
 211                         }
 212                     }
 213                     else if ( m_usesTexture0 || m_usesTexture1 )
 214                     {
 215                         mode = GL_MODULATE;
 216                         m_color = op->param1;
 217                     }
 218                     break;
 219                 case INTERPOLATE:
 220                     if ((op->param1 == TEXEL0) &&
 221                         ((op->param2 != TEXEL0) && (op->param2 != TEXEL0_ALPHA) &&
 222                          (op->param2 != TEXEL1) && (op->param2 != TEXEL1_ALPHA)) &&
 223                          (op->param3 == TEXEL0_ALPHA))
 224                     {
 225                         mode = GL_DECAL;
 226                         m_color = op->param2;
 227                         m_usesTexture0 = true;
 228                         m_usesTexture1 = false;
 229                     }
 230                     else if ((op->param1 == TEXEL0) &&
 231                         ((op->param2 != TEXEL0) && (op->param2 != TEXEL0_ALPHA) &&
 232                          (op->param2 != TEXEL1) && (op->param2 != TEXEL1_ALPHA)) &&
 233                          (op->param3 == TEXEL0_ALPHA))
 234                     {
 235                         mode = GL_DECAL;
 236                         m_color = op->param2;
 237                         m_usesTexture0 = false;
 238                         m_usesTexture1 = true;
 239                     }
 240                     break;
 241             }
 242         }
 243     }
 244
 245     texEnv->usesT0         = m_usesTexture0;
 246     texEnv->usesT1         = m_usesTexture1;
 247     texEnv->mode           = mode;
 248     texEnv->vertex.color   = m_color;
 249     texEnv->vertex.alpha   = m_alpha;
 250     return texEnv;
 251 }