src/OpenGLUtils/OpenGLUtils_FrameBuffer.cxx

   1 // Copyright (C) 2007-2016  CEA/DEN, EDF R&D, OPEN CASCADE
   2 //
   3 // This library is free software; you can redistribute it and/or
   4 // modify it under the terms of the GNU Lesser General Public
   5 // License as published by the Free Software Foundation; either
   6 // version 2.1 of the License, or (at your option) any later version.
   7 //
   8 // This library is distributed in the hope that it will be useful,
   9 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  10 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11 // Lesser General Public License for more details.
  12 //
  13 // You should have received a copy of the GNU Lesser General Public
  14 // License along with this library; if not, write to the Free Software
  15 // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  16 //
  17 // See http://www.salome-platform.org/ or email : webmaster.salome@opencascade.com
  18 //
  19
  20 //  File   : OpenGLUtils_FrameBuffer.cxx
  21 //  Module : SALOME
  22 //
  23 #ifdef VTK_OPENGL2
  24 #define GL_GLEXT_PROTOTYPES
  25 #endif
  26
  27 #include "OpenGLUtils_FrameBuffer.h"
  28
  29 #include <utilities.h>
  30
  31 #include <cstring>
  32
  33 #ifndef WIN32
  34 # ifndef GLX_GLXEXT_LEGACY
  35 #  define GLX_GLXEXT_LEGACY
  36 # endif
  37 # include <GL/glx.h>
  38 # include <dlfcn.h>
  39 #else
  40 # include <wingdi.h>
  41 #endif
  42
  43 #ifndef APIENTRY
  44 #define APIENTRY
  45 #endif
  46 #ifndef APIENTRYP
  47 #define APIENTRYP APIENTRY *
  48 #endif
  49
  50 #ifndef GL_FRAMEBUFFER_EXT
  51 #define GL_FRAMEBUFFER_EXT                0x8D40
  52 #endif
  53
  54 #ifndef GL_RENDERBUFFER_EXT
  55 #define GL_RENDERBUFFER_EXT               0x8D41
  56 #endif
  57
  58 #ifndef GL_COLOR_ATTACHMENT0_EXT
  59 #define GL_COLOR_ATTACHMENT0_EXT          0x8CE0
  60 #endif
  61
  62 #ifndef GL_DEPTH_ATTACHMENT_EXT
  63 #define GL_DEPTH_ATTACHMENT_EXT           0x8D00
  64 #endif
  65
  66 #ifndef GL_FRAMEBUFFER_COMPLETE_EXT
  67 #define GL_FRAMEBUFFER_COMPLETE_EXT       0x8CD5
  68 #endif
  69
  70 typedef void (APIENTRYP PFNGLGENFRAMEBUFFERSEXTPROC) (GLsizei n, GLuint *framebuffers);
  71 typedef void (APIENTRYP PFNGLBINDFRAMEBUFFEREXTPROC) (GLenum target, GLuint framebuffer);
  72 typedef void (APIENTRYP PFNGLFRAMEBUFFERTEXTURE2DEXTPROC) (GLenum target, GLenum attachment, GLenum textarget, GLuint texture, GLint level);
  73 typedef GLenum (APIENTRYP PFNGLCHECKFRAMEBUFFERSTATUSEXTPROC) (GLenum target);
  74 typedef void (APIENTRYP PFNGLDELETEFRAMEBUFFERSEXTPROC) (GLsizei n, const GLuint *framebuffers);
  75 typedef void (APIENTRYP PFNGLGENRENDERBUFFERSEXTPROC) (GLsizei n, GLuint *renderbuffers);
  76 typedef void (APIENTRYP PFNGLBINDRENDERBUFFEREXTPROC) (GLenum target, GLuint renderbuffer);
  77 typedef void (APIENTRYP PFNGLRENDERBUFFERSTORAGEEXTPROC) (GLenum target, GLenum internalformat, GLsizei width, GLsizei height);
  78 typedef void (APIENTRYP PFNGLFRAMEBUFFERRENDERBUFFEREXTPROC) (GLenum target, GLenum attachment, GLenum renderbuffertarget, GLuint renderbuffer);
  79 typedef void (APIENTRYP PFNGLDELETERENDERBUFFERSEXTPROC) (GLsizei n, const GLuint *renderbuffers);
  80
  81 static PFNGLGENFRAMEBUFFERSEXTPROC vglGenFramebuffersEXT = NULL;
  82 static PFNGLBINDFRAMEBUFFEREXTPROC vglBindFramebufferEXT = NULL;
  83 static PFNGLFRAMEBUFFERTEXTURE2DEXTPROC vglFramebufferTexture2DEXT = NULL;
  84 static PFNGLCHECKFRAMEBUFFERSTATUSEXTPROC vglCheckFramebufferStatusEXT = NULL;
  85 static PFNGLDELETEFRAMEBUFFERSEXTPROC vglDeleteFramebuffersEXT = NULL;
  86 static PFNGLGENRENDERBUFFERSEXTPROC vglGenRenderbuffersEXT = NULL;
  87 static PFNGLBINDRENDERBUFFEREXTPROC vglBindRenderbufferEXT = NULL;
  88 static PFNGLRENDERBUFFERSTORAGEEXTPROC vglRenderbufferStorageEXT = NULL;
  89 static PFNGLFRAMEBUFFERRENDERBUFFEREXTPROC vglFramebufferRenderbufferEXT = NULL;
  90 static PFNGLDELETERENDERBUFFERSEXTPROC vglDeleteRenderbuffersEXT = NULL;
  91
  92 #ifndef WIN32
  93 #define GL_GetProcAddress( x ) glXGetProcAddressARB( (const GLubyte*)x )
  94 #else
  95 #define GL_GetProcAddress( x ) wglGetProcAddress( (const LPCSTR)x )
  96 #endif
  97
  98 bool InitializeEXT()
  99 {
 100   vglGenFramebuffersEXT = (PFNGLGENFRAMEBUFFERSEXTPROC)GL_GetProcAddress( "glGenFramebuffersEXT" );
 101   vglBindFramebufferEXT = (PFNGLBINDFRAMEBUFFEREXTPROC)GL_GetProcAddress( "glBindFramebufferEXT" );
 102   vglFramebufferTexture2DEXT = (PFNGLFRAMEBUFFERTEXTURE2DEXTPROC)GL_GetProcAddress( "glFramebufferTexture2DEXT" );
 103   vglCheckFramebufferStatusEXT = (PFNGLCHECKFRAMEBUFFERSTATUSEXTPROC)GL_GetProcAddress( "glCheckFramebufferStatusEXT" );
 104   vglDeleteFramebuffersEXT = (PFNGLDELETEFRAMEBUFFERSEXTPROC)GL_GetProcAddress( "glDeleteFramebuffersEXT" );
 105   vglGenRenderbuffersEXT = (PFNGLGENRENDERBUFFERSEXTPROC)GL_GetProcAddress( "glGenRenderbuffersEXT" );
 106   vglBindRenderbufferEXT = (PFNGLBINDRENDERBUFFEREXTPROC)GL_GetProcAddress( "glBindRenderbufferEXT" );
 107   vglRenderbufferStorageEXT = (PFNGLRENDERBUFFERSTORAGEEXTPROC)GL_GetProcAddress( "glRenderbufferStorageEXT" );
 108   vglFramebufferRenderbufferEXT = (PFNGLFRAMEBUFFERRENDERBUFFEREXTPROC)GL_GetProcAddress( "glFramebufferRenderbufferEXT" );
 109   vglDeleteRenderbuffersEXT = (PFNGLDELETERENDERBUFFERSEXTPROC)GL_GetProcAddress( "glDeleteRenderbuffersEXT" );
 110
 111   bool ok = vglGenFramebuffersEXT && vglBindFramebufferEXT && vglFramebufferTexture2DEXT &&
 112             vglCheckFramebufferStatusEXT && vglDeleteFramebuffersEXT && vglGenRenderbuffersEXT &&
 113             vglBindRenderbufferEXT && vglRenderbufferStorageEXT && vglFramebufferRenderbufferEXT &&
 114             vglDeleteRenderbuffersEXT;
 115
 116   return ok;
 117 }
 118
 119 static bool IsEXTInitialized = InitializeEXT();
 120
 121 OpenGLUtils_FrameBuffer::OpenGLUtils_FrameBuffer()
 122   : textureId( 0 ),
 123     fboId( 0 ),
 124     rboId( 0 )
 125 {
 126 }
 127
 128 OpenGLUtils_FrameBuffer::~OpenGLUtils_FrameBuffer()
 129 {
 130   release();
 131 }
 132
 133 bool OpenGLUtils_FrameBuffer::init( const GLsizei& xSize, const GLsizei& ySize )
 134 {
 135 #ifdef VTK_OPENGL2
 136   int n = 0;
 137   std::ostringstream strm;
 138   glGetIntegerv(GL_NUM_EXTENSIONS, &n);
 139   for (int i = 0; i < n; i++)
 140     {
 141       const char *exti = (const char *)glGetStringi(GL_EXTENSIONS, i);
 142       strm<< exti <<" ";
 143     }
 144   std::string s = strm.str();
 145   const char* ext = s.c_str();
 146 #else
 147   char* ext = (char*)glGetString( GL_EXTENSIONS );
 148 #endif
 149   if( !IsEXTInitialized || !ext ||
 150       strstr( ext, "GL_EXT_framebuffer_object" ) == NULL )
 151   {
 152     MESSAGE( "Initializing OpenGL FrameBuffer extension failed" );
 153     return false;
 154   }
 155
 156   // create a texture object
 157   glEnable( GL_TEXTURE_2D );
 158   glGenTextures( 1, &textureId );
 159   glBindTexture( GL_TEXTURE_2D, textureId );
 160   glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR );
 161   glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR );
 162   glTexImage2D( GL_TEXTURE_2D, 0, GL_RGBA8, xSize, ySize, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL );
 163   glBindTexture( GL_TEXTURE_2D, 0 );
 164
 165   // create a renderbuffer object to store depth info
 166   vglGenRenderbuffersEXT( 1, &rboId );
 167   vglBindRenderbufferEXT( GL_RENDERBUFFER_EXT, rboId );
 168   vglRenderbufferStorageEXT( GL_RENDERBUFFER_EXT, GL_DEPTH_COMPONENT, xSize, ySize );
 169   vglBindRenderbufferEXT( GL_RENDERBUFFER_EXT, 0 );
 170
 171   // create a framebuffer object
 172   vglGenFramebuffersEXT( 1, &fboId );
 173   vglBindFramebufferEXT( GL_FRAMEBUFFER_EXT, fboId );
 174
 175   // attach the texture to FBO color attachment point
 176   vglFramebufferTexture2DEXT( GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT, GL_TEXTURE_2D, textureId, 0 );
 177
 178   // attach the renderbuffer to depth attachment point
 179   vglFramebufferRenderbufferEXT( GL_FRAMEBUFFER_EXT, GL_DEPTH_ATTACHMENT_EXT, GL_RENDERBUFFER_EXT, rboId );
 180
 181   // check FBO status
 182   GLenum status = vglCheckFramebufferStatusEXT( GL_FRAMEBUFFER_EXT );
 183
 184   // Unbind FBO
 185   vglBindFramebufferEXT( GL_FRAMEBUFFER_EXT, 0 );
 186
 187   return status == GL_FRAMEBUFFER_COMPLETE_EXT;
 188 }
 189
 190 void OpenGLUtils_FrameBuffer::release()
 191 {
 192   if( !IsEXTInitialized )
 193     return;
 194
 195   glDeleteTextures( 1, &textureId );
 196   textureId = 0;
 197
 198   vglDeleteFramebuffersEXT( 1, &fboId );
 199   fboId = 0;
 200
 201   vglDeleteRenderbuffersEXT( 1, &rboId );
 202   rboId = 0;
 203 }
 204
 205 void OpenGLUtils_FrameBuffer::bind()
 206 {
 207   if( !IsEXTInitialized )
 208     return;
 209
 210   vglBindFramebufferEXT( GL_FRAMEBUFFER_EXT, fboId );
 211 }
 212
 213 void OpenGLUtils_FrameBuffer::unbind()
 214 {
 215   if( !IsEXTInitialized )
 216     return;
 217
 218   vglBindFramebufferEXT( GL_FRAMEBUFFER_EXT, 0 );
 219 }