Manpages - SDL_GL_GetProcAddress.3

SDL_GL_GetProcAddress - Get the address of a GL function

#include “SDL.h”

void *SDL_GL_GetProcAddress*(*const char proc*);

Returns the address of the GL function proc, or NULL if the function is not found. If the GL library is loaded at runtime, with SDL_GL_LoadLibrary, then all GL functions must be retrieved this way. Usually this is used to retrieve function pointers to OpenGL extensions.

  typedef void (*GL_ActiveTextureARB_Func)(unsigned int);
  GL_ActiveTextureARB_Func glActiveTextureARB_ptr = 0;
  int has_multitexture=1;
  .
  .
  .
  /* Get function pointer */
  glActiveTextureARB_ptr=(GL_ActiveTextureARB_Func) SDL_GL_GetProcAddress("glActiveTextureARB");

  /* Check for a valid function ptr */
  if(!glActiveTextureARB_ptr){
    fprintf(stderr, "Multitexture Extensions not present.
  ");
    has_multitexture=0;
  }
  .
  .
  .
  .
  if(has_multitexture){
    glActiveTextureARB_ptr(GL_TEXTURE0_ARB);
    .
    .
  }
  else{
    .
    .
  }

SDL_GL_LoadLibrary