src/OpenGLUtils/OpenGLUtils_FrameBuffer.cxx

   1 // Copyright (C) 2007-2023  CEA, EDF, 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
  28 #include "OpenGLUtils_FrameBuffer.h"
  29
  30 #include <utilities.h>
  31
  32 #include <cstring>
  33
  34 #ifndef WIN32
  35 # ifndef GLX_GLXEXT_LEGACY
  36 #  define GLX_GLXEXT_LEGACY
  37 # endif
  38 #ifdef __APPLE__
  39 #import <mach-o/dyld.h>
  40 #import <stdlib.h>
  41 #import <string.h>
  42 void * glXGetProcAddressARB (const GLubyte *name)
  43
  44 {
  45     NSSymbol symbol;
  46     char *symbolName;
  47     symbolName = (char *)malloc (strlen ((const char *)name) + 2); // 1
  48     strcpy(symbolName + 1, (const char *)name); // 2
  49     symbolName[0] = '_'; // 3
  50     symbol = NULL;
  51     if (NSIsSymbolNameDefined (symbolName)) // 4
  52         symbol = NSLookupAndBindSymbol (symbolName);
  53     free (symbolName); // 5
  54     return symbol ? NSAddressOfSymbol (symbol) : NULL; // 6
  55 }
  56 #else
  57 # include <GL/glx.h>
  58 #endif
  59 # include <dlfcn.h>
  60 #else
  61 # include <wingdi.h>
  62 #endif
  63
  64 #ifndef APIENTRY
  65 #define APIENTRY
  66 #endif
  67 #ifndef APIENTRYP
  68 #define APIENTRYP APIENTRY *
  69 #endif
  70
  71 #ifndef GL_FRAMEBUFFER_EXT
  72 #define GL_FRAMEBUFFER_EXT                0x8D40
  73 #endif
  74
  75 #ifndef GL_RENDERBUFFER_EXT
  76 #define GL_RENDERBUFFER_EXT               0x8D41
  77 #endif
  78
  79 #ifndef GL_COLOR_ATTACHMENT0_EXT
  80 #define GL_COLOR_ATTACHMENT0_EXT          0x8CE0
  81 #endif
  82
  83 #ifndef GL_DEPTH_ATTACHMENT_EXT
  84 #define GL_DEPTH_ATTACHMENT_EXT           0x8D00
  85 #endif
  86
  87 #ifndef GL_FRAMEBUFFER_COMPLETE_EXT
  88 #define GL_FRAMEBUFFER_COMPLETE_EXT       0x8CD5
  89 #endif
  90
  91 typedef void (APIENTRYP PFNGLGENFRAMEBUFFERSEXTPROC) (GLsizei n, GLuint *framebuffers);
  92 typedef void (APIENTRYP PFNGLBINDFRAMEBUFFEREXTPROC) (GLenum target, GLuint framebuffer);
  93 typedef void (APIENTRYP PFNGLFRAMEBUFFERTEXTURE2DEXTPROC) (GLenum target, GLenum attachment, GLenum textarget, GLuint texture, GLint level);
  94 typedef GLenum (APIENTRYP PFNGLCHECKFRAMEBUFFERSTATUSEXTPROC) (GLenum target);
  95 typedef void (APIENTRYP PFNGLDELETEFRAMEBUFFERSEXTPROC) (GLsizei n, const GLuint *framebuffers);
  96 typedef void (APIENTRYP PFNGLGENRENDERBUFFERSEXTPROC) (GLsizei n, GLuint *renderbuffers);
  97 typedef void (APIENTRYP PFNGLBINDRENDERBUFFEREXTPROC) (GLenum target, GLuint renderbuffer);
  98 typedef void (APIENTRYP PFNGLRENDERBUFFERSTORAGEEXTPROC) (GLenum target, GLenum internalformat, GLsizei width, GLsizei height);
  99 typedef void (APIENTRYP PFNGLFRAMEBUFFERRENDERBUFFEREXTPROC) (GLenum target, GLenum attachment, GLenum renderbuffertarget, GLuint renderbuffer);
 100 typedef void (APIENTRYP PFNGLDELETERENDERBUFFERSEXTPROC) (GLsizei n, const GLuint *renderbuffers);
 101
 102 static PFNGLGENFRAMEBUFFERSEXTPROC vglGenFramebuffersEXT = NULL;
 103 static PFNGLBINDFRAMEBUFFEREXTPROC vglBindFramebufferEXT = NULL;
 104 static PFNGLFRAMEBUFFERTEXTURE2DEXTPROC vglFramebufferTexture2DEXT = NULL;
 105 static PFNGLCHECKFRAMEBUFFERSTATUSEXTPROC vglCheckFramebufferStatusEXT = NULL;
 106 static PFNGLDELETEFRAMEBUFFERSEXTPROC vglDeleteFramebuffersEXT = NULL;
 107 static PFNGLGENRENDERBUFFERSEXTPROC vglGenRenderbuffersEXT = NULL;
 108 static PFNGLBINDRENDERBUFFEREXTPROC vglBindRenderbufferEXT = NULL;
 109 static PFNGLRENDERBUFFERSTORAGEEXTPROC vglRenderbufferStorageEXT = NULL;
 110 static PFNGLFRAMEBUFFERRENDERBUFFEREXTPROC vglFramebufferRenderbufferEXT = NULL;
 111 static PFNGLDELETERENDERBUFFERSEXTPROC vglDeleteRenderbuffersEXT = NULL;
 112
 113 #ifndef WIN32
 114 #define GL_GetProcAddress( x ) glXGetProcAddressARB( (const GLubyte*)x )
 115 #else
 116 #define GL_GetProcAddress( x ) wglGetProcAddress( (const LPCSTR)x )
 117 #endif
 118
 119 bool InitializeEXT()
 120 {
 121   vglGenFramebuffersEXT = (PFNGLGENFRAMEBUFFERSEXTPROC)GL_GetProcAddress( "glGenFramebuffersEXT" );
 122   vglBindFramebufferEXT = (PFNGLBINDFRAMEBUFFEREXTPROC)GL_GetProcAddress( "glBindFramebufferEXT" );
 123   vglFramebufferTexture2DEXT = (PFNGLFRAMEBUFFERTEXTURE2DEXTPROC)GL_GetProcAddress( "glFramebufferTexture2DEXT" );
 124   vglCheckFramebufferStatusEXT = (PFNGLCHECKFRAMEBUFFERSTATUSEXTPROC)GL_GetProcAddress( "glCheckFramebufferStatusEXT" );
 125   vglDeleteFramebuffersEXT = (PFNGLDELETEFRAMEBUFFERSEXTPROC)GL_GetProcAddress( "glDeleteFramebuffersEXT" );
 126   vglGenRenderbuffersEXT = (PFNGLGENRENDERBUFFERSEXTPROC)GL_GetProcAddress( "glGenRenderbuffersEXT" );
 127   vglBindRenderbufferEXT = (PFNGLBINDRENDERBUFFEREXTPROC)GL_GetProcAddress( "glBindRenderbufferEXT" );
 128   vglRenderbufferStorageEXT = (PFNGLRENDERBUFFERSTORAGEEXTPROC)GL_GetProcAddress( "glRenderbufferStorageEXT" );
 129   vglFramebufferRenderbufferEXT = (PFNGLFRAMEBUFFERRENDERBUFFEREXTPROC)GL_GetProcAddress( "glFramebufferRenderbufferEXT" );
 130   vglDeleteRenderbuffersEXT = (PFNGLDELETERENDERBUFFERSEXTPROC)GL_GetProcAddress( "glDeleteRenderbuffersEXT" );
 131
 132   bool ok = vglGenFramebuffersEXT && vglBindFramebufferEXT && vglFramebufferTexture2DEXT &&
 133             vglCheckFramebufferStatusEXT && vglDeleteFramebuffersEXT && vglGenRenderbuffersEXT &&
 134             vglBindRenderbufferEXT && vglRenderbufferStorageEXT && vglFramebufferRenderbufferEXT &&
 135             vglDeleteRenderbuffersEXT;
 136
 137   return ok;
 138 }
 139
 140 static bool IsEXTInitialized = InitializeEXT();
 141
 142 OpenGLUtils_FrameBuffer::OpenGLUtils_FrameBuffer()
 143   : textureId( 0 ),
 144     fboId( 0 ),
 145     rboId( 0 )
 146 {
 147 }
 148
 149 OpenGLUtils_FrameBuffer::~OpenGLUtils_FrameBuffer()
 150 {
 151   release();
 152 }
 153
 154 bool OpenGLUtils_FrameBuffer::init( const GLsizei& xSize, const GLsizei& ySize )
 155 {
 156 #if defined(VTK_OPENGL2) && ! defined(WIN32)
 157   int n = 0;
 158   std::ostringstream strm;
 159   glGetIntegerv(GL_NUM_EXTENSIONS, &n);
 160   for (int i = 0; i < n; i++)
 161     {
 162       const char *exti = (const char *)glGetStringi(GL_EXTENSIONS, i);
 163       strm<< exti <<" ";
 164     }
 165   std::string s = strm.str();
 166   const char* ext = s.c_str();
 167 #else
 168   char* ext = (char*)glGetString( GL_EXTENSIONS );
 169 #endif
 170   if( !IsEXTInitialized || !ext ||
 171       strstr( ext, "GL_EXT_framebuffer_object" ) == NULL )
 172   {
 173     MESSAGE( "Initializing OpenGL FrameBuffer extension failed" );
 174     return false;
 175   }
 176
 177   // create a texture object
 178   glEnable( GL_TEXTURE_2D );
 179   glGenTextures( 1, &textureId );
 180   glBindTexture( GL_TEXTURE_2D, textureId );
 181   glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR );
 182   glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR );
 183   glTexImage2D( GL_TEXTURE_2D, 0, GL_RGBA8, xSize, ySize, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL );
 184   glBindTexture( GL_TEXTURE_2D, 0 );
 185
 186   // create a renderbuffer object to store depth info
 187   vglGenRenderbuffersEXT( 1, &rboId );
 188   vglBindRenderbufferEXT( GL_RENDERBUFFER_EXT, rboId );
 189   vglRenderbufferStorageEXT( GL_RENDERBUFFER_EXT, GL_DEPTH_COMPONENT, xSize, ySize );
 190   vglBindRenderbufferEXT( GL_RENDERBUFFER_EXT, 0 );
 191
 192   // create a framebuffer object
 193   vglGenFramebuffersEXT( 1, &fboId );
 194   vglBindFramebufferEXT( GL_FRAMEBUFFER_EXT, fboId );
 195
 196   // attach the texture to FBO color attachment point
 197   vglFramebufferTexture2DEXT( GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT, GL_TEXTURE_2D, textureId, 0 );
 198
 199   // attach the renderbuffer to depth attachment point
 200   vglFramebufferRenderbufferEXT( GL_FRAMEBUFFER_EXT, GL_DEPTH_ATTACHMENT_EXT, GL_RENDERBUFFER_EXT, rboId );
 201
 202   // check FBO status
 203   GLenum status = vglCheckFramebufferStatusEXT( GL_FRAMEBUFFER_EXT );
 204
 205   // Unbind FBO
 206   vglBindFramebufferEXT( GL_FRAMEBUFFER_EXT, 0 );
 207
 208   return status == GL_FRAMEBUFFER_COMPLETE_EXT;
 209 }
 210
 211 void OpenGLUtils_FrameBuffer::release()
 212 {
 213   if( !IsEXTInitialized )
 214     return;
 215
 216   glDeleteTextures( 1, &textureId );
 217   textureId = 0;
 218
 219   vglDeleteFramebuffersEXT( 1, &fboId );
 220   fboId = 0;
 221
 222   vglDeleteRenderbuffersEXT( 1, &rboId );
 223   rboId = 0;
 224 }
 225
 226 void OpenGLUtils_FrameBuffer::bind()
 227 {
 228   if( !IsEXTInitialized )
 229     return;
 230
 231   vglBindFramebufferEXT( GL_FRAMEBUFFER_EXT, fboId );
 232 }
 233
 234 void OpenGLUtils_FrameBuffer::unbind()
 235 {
 236   if( !IsEXTInitialized )
 237     return;
 238
 239   vglBindFramebufferEXT( GL_FRAMEBUFFER_EXT, 0 );
 240 }