static bool is_wgl_extension_supported(const char *extension, HDC dc)
{
_ALLEGRO_wglGetExtensionsStringARB_t _wglGetExtensionsStringARB;
int ret;
/* XXX deprecated in OpenGL 3.0 */
if (!glGetString(GL_EXTENSIONS))
return false;
_wglGetExtensionsStringARB = (_ALLEGRO_wglGetExtensionsStringARB_t)
wglGetProcAddress("wglGetExtensionsStringARB");
if (!_wglGetExtensionsStringARB)
return false;
ret = _al_ogl_look_for_an_extension(extension,
(const GLubyte*)_wglGetExtensionsStringARB(dc));
return ret;
}
PROC wglGetExtentionsProcAddress(HDC hdc,const char *extension_name,const char* proc_name)
{
// this is pointer to function which returns pointer to string with list of all wgl extensions
PFNWGLGETEXTENSIONSSTRINGARBPROC _wglGetExtensionsStringARB = NULL;
// determine pointer to wglGetExtensionsStringEXT function
_wglGetExtensionsStringARB = (PFNWGLGETEXTENSIONSSTRINGARBPROC) wglGetProcAddress("wglGetExtensionsStringARB");
if(!_wglGetExtensionsStringARB){
fprintf(stderr,"could not get wglGetExtensionsStringARB\n");
return NULL;
}
if (!_wglGetExtensionsStringARB || strstr(_wglGetExtensionsStringARB(hdc), extension_name) == NULL)
{
fprintf(stderr,"extension %s was not found\n",extension_name);
// string was not found
return NULL;
}
// extension is supported
return wglGetProcAddress(proc_name);
}
int _glfwPlatformExtensionSupported( const char *extension )
{
const GLubyte *extensions;
WGLGETEXTENSIONSSTRINGEXT_T _wglGetExtensionsStringEXT;
WGLGETEXTENSIONSSTRINGARB_T _wglGetExtensionsStringARB;
// Try wglGetExtensionsStringEXT
_wglGetExtensionsStringEXT = (WGLGETEXTENSIONSSTRINGEXT_T)
wglGetProcAddress( "wglGetExtensionsStringEXT" );
if( _wglGetExtensionsStringEXT != NULL )
{
extensions = (GLubyte *) _wglGetExtensionsStringEXT();
if( extensions != NULL )
{
if( _glfwStringInExtensionString( extension, extensions ) )
{
return GL_TRUE;
}
}
}
// Try wglGetExtensionsStringARB
_wglGetExtensionsStringARB = (WGLGETEXTENSIONSSTRINGARB_T)
wglGetProcAddress( "wglGetExtensionsStringARB" );
if( _wglGetExtensionsStringARB != NULL )
{
extensions = (GLubyte *) _wglGetExtensionsStringARB(_glfwWin.DC);
if( extensions != NULL )
{
if( _glfwStringInExtensionString( extension, extensions ) )
{
return GL_TRUE;
}
}
}
return GL_FALSE;
}
static bool _ogl_is_extension_supported(const char *extension,
ALLEGRO_DISPLAY *disp)
{
int ret = 0;
GLubyte const *ext_str;
#if !defined ALLEGRO_IPHONE && !defined ALLEGRO_ANDROID
int v = al_get_opengl_version();
#endif
(void)disp;
#if defined ALLEGRO_GP2XWIZ
return false;
#endif
#if !defined ALLEGRO_IPHONE && !defined ALLEGRO_ANDROID
if (disp->flags & ALLEGRO_OPENGL_3_0 || v >= _ALLEGRO_OPENGL_VERSION_3_0) {
int i;
GLint ext_cnt;
glGetIntegerv(GL_NUM_EXTENSIONS, &ext_cnt);
for (i = 0; i < ext_cnt; i++) {
ext_str = glGetStringi(GL_EXTENSIONS, i);
if (ext_str && !strcmp(extension, (char*)ext_str)) {
ret = 1;
break;
}
}
}
else
#endif
{
ext_str = glGetString(GL_EXTENSIONS);
if (!ext_str)
return false;
ret = _al_ogl_look_for_an_extension(extension, ext_str);
}
#ifdef ALLEGRO_WINDOWS
if (!ret && strncmp(extension, "WGL", 3) == 0) {
ALLEGRO_DISPLAY_WGL *wgl_disp = (void*)disp;
_ALLEGRO_wglGetExtensionsStringARB_t _wglGetExtensionsStringARB;
if (!wgl_disp->dc)
return false;
_wglGetExtensionsStringARB = (void *)
wglGetProcAddress("wglGetExtensionsStringARB");
if (_wglGetExtensionsStringARB) {
ret = _al_ogl_look_for_an_extension(extension, (const GLubyte *)
_wglGetExtensionsStringARB(wgl_disp->dc));
}
}
#elif defined ALLEGRO_UNIX && !defined ALLEGRO_EXCLUDE_GLX
if (!ret && strncmp(extension, "GLX", 3) == 0) {
ALLEGRO_SYSTEM_XGLX *sys = (void*)al_get_system_driver();
ALLEGRO_DISPLAY_XGLX *glx_disp = (void*)disp;
char const *ext;
if (!sys->gfxdisplay)
return false;
ext = glXQueryExtensionsString(sys->gfxdisplay, glx_disp->xscreen);
if (!ext) {
/* work around driver bugs? */
ext = "";
}
ret = _al_ogl_look_for_an_extension(extension, (const GLubyte *)ext);
}
#endif
return ret;
}
