text: /*
  -----------------------------------------------------------------------------
  This source file is part of OGRE
      (Object-oriented Graphics Rendering Engine)
  For the latest info, see http://www.ogre3d.org/
  
  Copyright (c) 2000-2014 Torus Knot Software Ltd
  
  Permission is hereby granted, free of charge, to any person obtaining a copy
  of this software and associated documentation files (the "Software"), to deal
  in the Software without restriction, including without limitation the rights
  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  copies of the Software, and to permit persons to whom the Software is
  furnished to do so, subject to the following conditions:
  
  The above copyright notice and this permission notice shall be included in
  all copies or substantial portions of the Software.
  
  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  THE SOFTWARE.
  -----------------------------------------------------------------------------
  */
  
  #include "OgreGLSLExtSupport.h"
  #include "OgreGLSLLinkProgram.h"
  #include "OgreStringConverter.h"
  #include "OgreGLSLGpuProgram.h"
  #include "OgreGLSLProgram.h"
  #include "OgreGLSLLinkProgramManager.h"
  #include "OgreException.h"
  #include "OgreGpuProgramManager.h"
  
  namespace Ogre {
      namespace GLSL {
  
      //  a  builtin              custom attrib name
      // ----------------------------------------------
      //  0  gl_Vertex            vertex
      //  1  n/a                  blendWeights        
      //  2  gl_Normal            normal
      //  3  gl_Color             colour
      //  4  gl_SecondaryColor    secondary_colour
      //  5  gl_FogCoord          fog_coord
      //  7  n/a                  blendIndices
      //  8  gl_MultiTexCoord0    uv0
      //  9  gl_MultiTexCoord1    uv1
      //  10 gl_MultiTexCoord2    uv2
      //  11 gl_MultiTexCoord3    uv3
      //  12 gl_MultiTexCoord4    uv4
      //  13 gl_MultiTexCoord5    uv5
      //  14 gl_MultiTexCoord6    uv6, tangent
      //  15 gl_MultiTexCoord7    uv7, binormal
      GLSLLinkProgram::CustomAttribute GLSLLinkProgram::msCustomAttributes[] = {
          CustomAttribute("vertex", GLGpuProgram::getFixedAttributeIndex(VES_POSITION, 0)),
          CustomAttribute("blendWeights", GLGpuProgram::getFixedAttributeIndex(VES_BLEND_WEIGHTS, 0)),
          CustomAttribute("normal", GLGpuProgram::getFixedAttributeIndex(VES_NORMAL, 0)),
          CustomAttribute("colour", GLGpuProgram::getFixedAttributeIndex(VES_DIFFUSE, 0)),
          CustomAttribute("secondary_colour", GLGpuProgram::getFixedAttributeIndex(VES_SPECULAR, 0)),
          CustomAttribute("blendIndices", GLGpuProgram::getFixedAttributeIndex(VES_BLEND_INDICES, 0)),
          CustomAttribute("uv0", GLGpuProgram::getFixedAttributeIndex(VES_TEXTURE_COORDINATES, 0)),
          CustomAttribute("uv1", GLGpuProgram::getFixedAttributeIndex(VES_TEXTURE_COORDINATES, 1)),
          CustomAttribute("uv2", GLGpuProgram::getFixedAttributeIndex(VES_TEXTURE_COORDINATES, 2)),
          CustomAttribute("uv3", GLGpuProgram::getFixedAttributeIndex(VES_TEXTURE_COORDINATES, 3)),
          CustomAttribute("uv4", GLGpuProgram::getFixedAttributeIndex(VES_TEXTURE_COORDINATES, 4)),
          CustomAttribute("uv5", GLGpuProgram::getFixedAttributeIndex(VES_TEXTURE_COORDINATES, 5)),
          CustomAttribute("uv6", GLGpuProgram::getFixedAttributeIndex(VES_TEXTURE_COORDINATES, 6)),
          CustomAttribute("uv7", GLGpuProgram::getFixedAttributeIndex(VES_TEXTURE_COORDINATES, 7)),
          CustomAttribute("tangent", GLGpuProgram::getFixedAttributeIndex(VES_TANGENT, 0)),
          CustomAttribute("binormal", GLGpuProgram::getFixedAttributeIndex(VES_BINORMAL, 0)),
      };
  
      GLint getGLGeometryInputPrimitiveType(RenderOperation::OperationType operationType, bool requiresAdjacency)
      {
          switch (operationType)
          {
          case RenderOperation::OT_POINT_LIST:
              return GL_POINTS;
          case RenderOperation::OT_LINE_LIST:
          case RenderOperation::OT_LINE_STRIP:
              return requiresAdjacency ? GL_LINES_ADJACENCY_EXT : GL_LINES;
          default:
          case RenderOperation::OT_TRIANGLE_LIST:
          case RenderOperation::OT_TRIANGLE_STRIP:
          case RenderOperation::OT_TRIANGLE_FAN:
              return requiresAdjacency ? GL_TRIANGLES_ADJACENCY_EXT : GL_TRIANGLES;
          }
      }
      //-----------------------------------------------------------------------
      GLint getGLGeometryOutputPrimitiveType(RenderOperation::OperationType operationType)
      {
          switch (operationType)
          {
          case RenderOperation::OT_POINT_LIST:
              return GL_POINTS;
          case RenderOperation::OT_LINE_STRIP:
              return GL_LINE_STRIP;
          case RenderOperation::OT_TRIANGLE_STRIP:
              return GL_TRIANGLE_STRIP;
          default:
              OGRE_EXCEPT(Exception::ERR_RENDERINGAPI_ERROR,
                  "Geometry shader output operation type can only be point list,"
                  "line strip or triangle strip",
                              "GLSLLinkProgram::getGLGeometryOutputPrimitiveType");
          }
      }
  
      //-----------------------------------------------------------------------
      GLSLLinkProgram::GLSLLinkProgram(GLSLProgram* vertexProgram, GLSLProgram* geometryProgram, GLSLProgram* fragmentProgram)
          : mVertexProgram(vertexProgram)
          , mGeometryProgram(geometryProgram)
          , mFragmentProgram(fragmentProgram)
          , mUniformRefsBuilt(false)
          , mLinked(false)
          , mTriedToLinkAndFailed(false)
          , mSkeletalAnimation(false)
      {
          // Initialise uniform cache
          mUniformCache = new GLUniformCache();
      }
  
      //-----------------------------------------------------------------------
      GLSLLinkProgram::~GLSLLinkProgram(void)
      {
          glDeleteObjectARB(mGLHandle);
  
          delete mUniformCache;
          mUniformCache = 0;
      }
  
      //-----------------------------------------------------------------------
      void GLSLLinkProgram::activate(void)
      {
          if (!mLinked && !mTriedToLinkAndFailed)
          {           
              glGetError(); //Clean up the error. Otherwise will flood log.
  
              mGLHandle = glCreateProgramObjectARB();
  
              GLenum glErr = glGetError();
              if(glErr != GL_NO_ERROR)
              {
                  reportGLSLError( glErr, "GLSLLinkProgram::activate", "Error Creating GLSL Program Object", 0 );
              }
  
              if ( GpuProgramManager::getSingleton().canGetCompiledShaderBuffer() &&
                   GpuProgramManager::getSingleton().isMicrocodeAvailableInCache(getCombinedName()) )
              {
                  getMicrocodeFromCache();
              }
              else
              {
                  compileAndLink();
  
              }
              buildGLUniformReferences();
              extractAttributes();
          }
          if (mLinked)
          {
              GLenum glErr = glGetError();
              if(glErr != GL_NO_ERROR)
              {
                  reportGLSLError( glErr, "GLSLLinkProgram::Activate",
                      "Error prior to using GLSL Program Object : ", mGLHandle, false, false);
              }
  
              glUseProgramObjectARB( mGLHandle );
  
              glErr = glGetError();
              if(glErr != GL_NO_ERROR)
              {
                  reportGLSLError( glErr, "GLSLLinkProgram::Activate",
                      "Error using GLSL Program Object : ", mGLHandle, false, false);
              }
          }
      }
      //-----------------------------------------------------------------------
      void GLSLLinkProgram::getMicrocodeFromCache(void)
      {
          GpuProgramManager::Microcode cacheMicrocode = 
              GpuProgramManager::getSingleton().getMicrocodeFromCache(getCombinedName());
          
          GLenum binaryFormat = *((GLenum *)(cacheMicrocode->getPtr()));
          uint8 * programBuffer = cacheMicrocode->getPtr() + sizeof(GLenum);
          size_t sizeOfBuffer = cacheMicrocode->size() - sizeof(GLenum);
          glProgramBinary(mGLHandle, 
                          binaryFormat, 
                          programBuffer,
                          static_cast<GLsizei>(sizeOfBuffer)
                          );
  
          glGetProgramiv(mGLHandle, GL_LINK_STATUS, &mLinked);
          if (!mLinked)
          {
              //
              // Something must have changed since the program binaries
              // were cached away.  Fallback to source shader loading path,
              // and then retrieve and cache new program binaries once again.
              //
              compileAndLink();
          }
      }
      //-----------------------------------------------------------------------
      void GLSLLinkProgram::extractAttributes(void)
      {
          size_t numAttribs = sizeof(msCustomAttributes)/sizeof(CustomAttribute);
  
          for (size_t i = 0; i < numAttribs; ++i)
          {
              const CustomAttribute& a = msCustomAttributes[i];
              GLint attrib = glGetAttribLocationARB(mGLHandle, a.name.c_str());
  
              if (attrib != -1)
              {
                  mValidAttributes.insert(a.attrib);
              }
          }
      }
      //-----------------------------------------------------------------------
      GLuint GLSLLinkProgram::getAttributeIndex(VertexElementSemantic semantic, uint index)
      {
          return GLGpuProgram::getFixedAttributeIndex(semantic, index);
      }
      //-----------------------------------------------------------------------
      bool GLSLLinkProgram::isAttributeValid(VertexElementSemantic semantic, uint index)
      {
          return mValidAttributes.find(getAttributeIndex(semantic, index)) != mValidAttributes.end();
      }
      //-----------------------------------------------------------------------
      void GLSLLinkProgram::buildGLUniformReferences(void)
      {
          if (!mUniformRefsBuilt)
          {
              const GpuConstantDefinitionMap* vertParams = 0;
              const GpuConstantDefinitionMap* fragParams = 0;
              const GpuConstantDefinitionMap* geomParams = 0;
              if (mVertexProgram)
              {
                  vertParams = &(mVertexProgram->getConstantDefinitions().map);
              }
              if (mGeometryProgram)
              {
                  geomParams = &(mGeometryProgram->getConstantDefinitions().map);
              }
              if (mFragmentProgram)
              {
                  fragParams = &(mFragmentProgram->getConstantDefinitions().map);
              }
  
              GLSLLinkProgramManager::getSingleton().extractUniforms(
                  mGLHandle, vertParams, geomParams, fragParams, mGLUniformReferences);
  
              mUniformRefsBuilt = true;
          }
      }
  
      //-----------------------------------------------------------------------
      void GLSLLinkProgram::updateUniforms(GpuProgramParametersSharedPtr params, 
          uint16 mask, GpuProgramType fromProgType)
      {
          // iterate through uniform reference list and update uniform values
          GLUniformReferenceIterator currentUniform = mGLUniformReferences.begin();
          GLUniformReferenceIterator endUniform = mGLUniformReferences.end();
  
          // determine if we need to transpose matrices when binding
          int transpose = GL_TRUE;
          if ((fromProgType == GPT_FRAGMENT_PROGRAM && mVertexProgram && (!mVertexProgram->getColumnMajorMatrices())) ||
              (fromProgType == GPT_VERTEX_PROGRAM && mFragmentProgram && (!mFragmentProgram->getColumnMajorMatrices())) ||
              (fromProgType == GPT_GEOMETRY_PROGRAM && mGeometryProgram && (!mGeometryProgram->getColumnMajorMatrices())))
          {
              transpose = GL_FALSE;
          }
  
          for (;currentUniform != endUniform; ++currentUniform)
          {
              // Only pull values from buffer it's supposed to be in (vertex or fragment)
              // This method will be called twice, once for vertex program params, 
              // and once for fragment program params.
              if (fromProgType == currentUniform->mSourceProgType)
              {
                  const GpuConstantDefinition* def = currentUniform->mConstantDef;
                  if (def->variability & mask)
                  {
  
                      GLsizei glArraySize = (GLsizei)def->arraySize;
  
                      bool shouldUpdate = true;
  
                      switch (def->constType)
                      {
                          case GCT_INT1:
                          case GCT_INT2:
                          case GCT_INT3:
                          case GCT_INT4:
                          case GCT_SAMPLER1D:
                          case GCT_SAMPLER1DSHADOW:
                          case GCT_SAMPLER2D:
                          case GCT_SAMPLER2DSHADOW:
                          case GCT_SAMPLER2DARRAY:
                          case GCT_SAMPLER3D:
                          case GCT_SAMPLERCUBE:
                              shouldUpdate = mUniformCache->updateUniform(currentUniform->mLocation,
                                                                          params->getIntPointer(def->physicalIndex),
                                                                          static_cast<GLsizei>(def->elementSize * def->arraySize * sizeof(int)));
                              break;
                          default:
                              shouldUpdate = mUniformCache->updateUniform(currentUniform->mLocation,
                                                                          params->getFloatPointer(def->physicalIndex),
                                                                          static_cast<GLsizei>(def->elementSize * def->arraySize * sizeof(float)));
                              break;
  
                      }
  
                      if(!shouldUpdate)
                          continue;
  
                      // get the index in the parameter real list
                      switch (def->constType)
                      {
                      case GCT_FLOAT1:
                          glUniform1fvARB(currentUniform->mLocation, glArraySize, 
                              params->getFloatPointer(def->physicalIndex));
                          break;
                      case GCT_FLOAT2:
                          glUniform2fvARB(currentUniform->mLocation, glArraySize, 
                              params->getFloatPointer(def->physicalIndex));
                          break;
                      case GCT_FLOAT3:
                          glUniform3fvARB(currentUniform->mLocation, glArraySize, 
                              params->getFloatPointer(def->physicalIndex));
                          break;
                      case GCT_FLOAT4:
                          glUniform4fvARB(currentUniform->mLocation, glArraySize, 
                              params->getFloatPointer(def->physicalIndex));
                          break;
                      case GCT_MATRIX_2X2:
                          glUniformMatrix2fvARB(currentUniform->mLocation, glArraySize, 
                              transpose, params->getFloatPointer(def->physicalIndex));
                          break;
                      case GCT_MATRIX_2X3:
                          if (GLEW_VERSION_2_1)
                          {
                              glUniformMatrix2x3fv(currentUniform->mLocation, glArraySize, 
                                  transpose, params->getFloatPointer(def->physicalIndex));
                          }
                          break;
                      case GCT_MATRIX_2X4:
                          if (GLEW_VERSION_2_1)
                          {
                              glUniformMatrix2x4fv(currentUniform->mLocation, glArraySize, 
                                  transpose, params->getFloatPointer(def->physicalIndex));
                          }
                          break;
                      case GCT_MATRIX_3X2:
                          if (GLEW_VERSION_2_1)
                          {
                              glUniformMatrix3x2fv(currentUniform->mLocation, glArraySize, 
                                  transpose, params->getFloatPointer(def->physicalIndex));
                          }
                          break;
                      case GCT_MATRIX_3X3:
                          glUniformMatrix3fvARB(currentUniform->mLocation, glArraySize, 
                              transpose, params->getFloatPointer(def->physicalIndex));
                          break;
                      case GCT_MATRIX_3X4:
                          if (GLEW_VERSION_2_1)
                          {
                              glUniformMatrix3x4fv(currentUniform->mLocation, glArraySize, 
                                  transpose, params->getFloatPointer(def->physicalIndex));
                          }
                          break;
                      case GCT_MATRIX_4X2:
                          if (GLEW_VERSION_2_1)
                          {
                              glUniformMatrix4x2fv(currentUniform->mLocation, glArraySize, 
                                  transpose, params->getFloatPointer(def->physicalIndex));
                          }
                          break;
                      case GCT_MATRIX_4X3:
                          if (GLEW_VERSION_2_1)
                          {
                              glUniformMatrix4x3fv(currentUniform->mLocation, glArraySize, 
                                  transpose, params->getFloatPointer(def->physicalIndex));
                          }
                          break;
                      case GCT_MATRIX_4X4:
                          glUniformMatrix4fvARB(currentUniform->mLocation, glArraySize, 
                              transpose, params->getFloatPointer(def->physicalIndex));
                          break;
                      case GCT_INT1:
                          glUniform1ivARB(currentUniform->mLocation, glArraySize, 
                              (GLint*)params->getIntPointer(def->physicalIndex));
                          break;
                      case GCT_INT2:
                          glUniform2ivARB(currentUniform->mLocation, glArraySize, 
                              (GLint*)params->getIntPointer(def->physicalIndex));
                          break;
                      case GCT_INT3:
                          glUniform3ivARB(currentUniform->mLocation, glArraySize, 
                              (GLint*)params->getIntPointer(def->physicalIndex));
                          break;
                      case GCT_INT4:
                          glUniform4ivARB(currentUniform->mLocation, glArraySize, 
                              (GLint*)params->getIntPointer(def->physicalIndex));
                          break;
                      case GCT_SAMPLER1D:
                      case GCT_SAMPLER1DSHADOW:
                      case GCT_SAMPLER2D:
                      case GCT_SAMPLER2DSHADOW:
                                          case GCT_SAMPLER2DARRAY:
                      case GCT_SAMPLER3D:
                      case GCT_SAMPLERCUBE:
                          // samplers handled like 1-element ints
                          glUniform1ivARB(currentUniform->mLocation, 1, 
                              (GLint*)params->getIntPointer(def->physicalIndex));
                          break;
                      case GCT_UNKNOWN:
                      default:
                          break;
  
                      } // end switch
      #if OGRE_DEBUG_MODE
                      GLenum glErr = glGetError();
                      if(glErr != GL_NO_ERROR)
                      {
                          reportGLSLError( glErr, "GLSLLinkProgram::updateUniforms", "Error updating uniform", 0 );
                      }
      #endif
                  } // variability & mask
              } // fromProgType == currentUniform->mSourceProgType
    
          } // end for
      }
      //-----------------------------------------------------------------------
      void GLSLLinkProgram::updatePassIterationUniforms(GpuProgramParametersSharedPtr params)
      {
          if (params->hasPassIterationNumber())
          {
              size_t index = params->getPassIterationNumberIndex();
  
              GLUniformReferenceIterator currentUniform = mGLUniformReferences.begin();
              GLUniformReferenceIterator endUniform = mGLUniformReferences.end();
  
              // need to find the uniform that matches the multi pass entry
              for (;currentUniform != endUniform; ++currentUniform)
              {
                  // get the index in the parameter real list
                  if (index == currentUniform->mConstantDef->physicalIndex)
                  {
                      if(!mUniformCache->updateUniform(currentUniform->mLocation,
                                                       params->getFloatPointer(index),
                                                       static_cast<GLsizei>(currentUniform->mConstantDef->elementSize *
                                                       currentUniform->mConstantDef->arraySize *
                                                       sizeof(float))))
                          return;
                  }
              }
          }
  
      }
      //-----------------------------------------------------------------------
      Ogre::String GLSLLinkProgram::getCombinedName()
      {
          String name;
          if (mVertexProgram)
          {
              name += "Vertex Program:" ;
              name += mVertexProgram->getName();
          }
          if (mFragmentProgram)
          {
              name += " Fragment Program:" ;
              name += mFragmentProgram->getName();
          }
          if (mGeometryProgram)
          {
              name += " Geometry Program:" ;
              name += mGeometryProgram->getName();
          }
          return name;
      }
      //-----------------------------------------------------------------------
      void GLSLLinkProgram::compileAndLink()
      {
          if (mVertexProgram)
          {
              // compile and attach Vertex Program
              if (!mVertexProgram->compile(true))
              {
                  // todo error
                  return;
              }
              mVertexProgram->attachToProgramObject(mGLHandle);
              setSkeletalAnimationIncluded(mVertexProgram->isSkeletalAnimationIncluded());
  
              // Some drivers (e.g. OS X on nvidia) incorrectly determine the attribute binding automatically
  
              // and end up aliasing existing built-ins. So avoid! 
              // Bind all used attribs - not all possible ones otherwise we'll get 
              // lots of warnings in the log, and also may end up aliasing names used
              // as varyings by accident
              // Because we can't ask GL whether an attribute is used in the shader
              // until it is linked (chicken and egg!) we have to parse the source
  
              size_t numAttribs = sizeof(msCustomAttributes)/sizeof(CustomAttribute);
              const String& vpSource = mVertexProgram->getSource();
              for (size_t i = 0; i < numAttribs; ++i)
              {
                  const CustomAttribute& a = msCustomAttributes[i];
  
                  // we're looking for either: 
                  //   attribute vec<n> <semantic_name>
                  //   in vec<n> <semantic_name>
                  // The latter is recommended in GLSL 1.3 onwards 
                  // be slightly flexible about formatting
                  String::size_type pos = vpSource.find(a.name);
                  bool foundAttr = false;
                  while (pos != String::npos && !foundAttr)
                  {
                      String::size_type startpos = vpSource.find("attribute", pos < 20 ? 0 : pos-20);
                      if (startpos == String::npos)
                          startpos = vpSource.find("in", pos-20);
                      if (startpos != String::npos && startpos < pos)
                      {
                          // final check 
                          String expr = vpSource.substr(startpos, pos + a.name.length() - startpos);
                          StringVector vec = StringUtil::split(expr);
                          if ((vec[0] == "in" || vec[0] == "attribute") && vec[2] == a.name)
                          {
                              glBindAttribLocationARB(mGLHandle, a.attrib, a.name.c_str());
                              foundAttr = true;
                          }
                      }
                      // Find the position of the next occurrence if needed
                      pos = vpSource.find(a.name, pos + a.name.length());
                  }
              }
          }
  
          if (mGeometryProgram)
          {
              // compile and attach Geometry Program
              if (!mGeometryProgram->compile(true))
              {
                  // todo error
                  return;
              }
  
              mGeometryProgram->attachToProgramObject(mGLHandle);
  
              //Don't set adjacency flag. We handle it internally and expose "false"
  
              RenderOperation::OperationType inputOperationType = mGeometryProgram->getInputOperationType();
              glProgramParameteriEXT(mGLHandle, GL_GEOMETRY_INPUT_TYPE_EXT,
                  getGLGeometryInputPrimitiveType(inputOperationType, mGeometryProgram->isAdjacencyInfoRequired()));
  
              RenderOperation::OperationType outputOperationType = mGeometryProgram->getOutputOperationType();
  
              glProgramParameteriEXT(mGLHandle, GL_GEOMETRY_OUTPUT_TYPE_EXT,
                  getGLGeometryOutputPrimitiveType(outputOperationType));
  
              glProgramParameteriEXT(mGLHandle, GL_GEOMETRY_VERTICES_OUT_EXT,
                  mGeometryProgram->getMaxOutputVertices());
          }
  
          if (mFragmentProgram)
          {
              // compile and attach Fragment Program
              if (!mFragmentProgram->compile(true))
              {
                  // todo error
                  return;
              }       
              mFragmentProgram->attachToProgramObject(mGLHandle);
          }
  
          
          // now the link
  
          glLinkProgramARB( mGLHandle );
          glGetObjectParameterivARB( mGLHandle, GL_OBJECT_LINK_STATUS_ARB, &mLinked );
          mTriedToLinkAndFailed = !mLinked;
  
          // force logging and raise exception if not linked
          GLenum glErr = glGetError();
          if(glErr != GL_NO_ERROR)
          {
              reportGLSLError( glErr, "GLSLLinkProgram::compileAndLink",
                  "Error linking GLSL Program Object : ", mGLHandle, !mLinked, !mLinked );
          }
          
          if(mLinked)
          {
              logObjectInfo(  getCombinedName() + String(" GLSL link result : "), mGLHandle );
          }
  
          if (mLinked)
          {
              if ( GpuProgramManager::getSingleton().getSaveMicrocodesToCache() )
              {
                  // add to the microcode to the cache
                  String name;
                  name = getCombinedName();
  
                  // get buffer size
                  GLint binaryLength = 0;
                  glGetProgramiv(mGLHandle, GL_PROGRAM_BINARY_LENGTH, &binaryLength);
  
                  // turns out we need this param when loading
                  // it will be the first bytes of the array in the microcode
                  GLenum binaryFormat = 0; 
  
                  // create microcode
                  GpuProgramManager::Microcode newMicrocode = 
                      GpuProgramManager::getSingleton().createMicrocode(binaryLength + sizeof(GLenum));
  
                  // get binary
                  uint8 * programBuffer = newMicrocode->getPtr() + sizeof(GLenum);
                  glGetProgramBinary(mGLHandle, binaryLength, NULL, &binaryFormat, programBuffer);
  
                  // save binary format
                  memcpy(newMicrocode->getPtr(), &binaryFormat, sizeof(GLenum));
  
                  // add to the microcode to the cache
                  GpuProgramManager::getSingleton().addMicrocodeToCache(name, newMicrocode);
              }
          }
      }
      //-----------------------------------------------------------------------
  } // namespace GLSL
  } // namespace Ogre
  