//======================================================================== // GLFW - An OpenGL framework // File: glext.c // Platform: Any // API version: 2.6 // WWW: http://glfw.sourceforge.net //------------------------------------------------------------------------ // Copyright (c) 2002-2006 Camilla Berglund // // This software is provided 'as-is', without any express or implied // warranty. In no event will the authors be held liable for any damages // arising from the use of this software. // // Permission is granted to anyone to use this software for any purpose, // including commercial applications, and to alter it and redistribute it // freely, subject to the following restrictions: // // 1. The origin of this software must not be misrepresented; you must not // claim that you wrote the original software. If you use this software // in a product, an acknowledgment in the product documentation would // be appreciated but is not required. // // 2. Altered source versions must be plainly marked as such, and must not // be misrepresented as being the original software. // // 3. This notice may not be removed or altered from any source // distribution. // //------------------------------------------------------------------------ // $Id: glext.c,v 1.6 2007/03/15 03:20:19 elmindreda Exp $ //======================================================================== #include "internal.h" //************************************************************************ //**** GLFW internal functions **** //************************************************************************ //======================================================================== // _glfwStringInExtensionString() - Check if a string can be found in an // OpenGL extension string //======================================================================== int _glfwStringInExtensionString( const char *string, const GLubyte *extensions ) { const GLubyte *start; GLubyte *where, *terminator; // It takes a bit of care to be fool-proof about parsing the // OpenGL extensions string. Don't be fooled by sub-strings, // etc. start = extensions; while( 1 ) { where = (GLubyte *) strstr( (const char *) start, string ); if( !where ) { return GL_FALSE; } terminator = where + strlen( string ); if( where == start || *(where - 1) == ' ' ) { if( *terminator == ' ' || *terminator == '\0' ) { break; } } start = terminator; } return GL_TRUE; } //************************************************************************ //**** GLFW user functions **** //************************************************************************ //======================================================================== // glfwExtensionSupported() - Check if an OpenGL extension is available // at runtime //======================================================================== GLFWAPI int GLFWAPIENTRY glfwExtensionSupported( const char *extension ) { const GLubyte *extensions; GLubyte *where; // Is GLFW initialized? if( !_glfwInitialized || !_glfwWin.Opened ) { return GL_FALSE; } // Extension names should not have spaces where = (GLubyte *) strchr( extension, ' ' ); if( where || *extension == '\0' ) { return GL_FALSE; } // Check if extension is in the standard OpenGL extensions string extensions = (GLubyte *) glGetString( GL_EXTENSIONS ); if( extensions != NULL ) { if( _glfwStringInExtensionString( extension, extensions ) ) { return GL_TRUE; } } // Additional platform specific extension checking (e.g. WGL) if( _glfwPlatformExtensionSupported( extension ) ) { return GL_TRUE; } return GL_FALSE; } //======================================================================== // glfwGetProcAddress() - Get the function pointer to an OpenGL function. // This function can be used to get access to extended OpenGL functions. //======================================================================== GLFWAPI void * GLFWAPIENTRY glfwGetProcAddress( const char *procname ) { // Is GLFW initialized? if( !_glfwInitialized || !_glfwWin.Opened ) { return NULL; } return _glfwPlatformGetProcAddress( procname ); } //======================================================================== // glfwGetGLVersion() - Get OpenGL version //======================================================================== GLFWAPI void GLFWAPIENTRY glfwGetGLVersion( int *major, int *minor, int *rev ) { GLuint _major, _minor = 0, _rev = 0; const GLubyte *version; GLubyte *ptr; // Is GLFW initialized? if( !_glfwInitialized || !_glfwWin.Opened ) { return; } // Get OpenGL version string version = glGetString( GL_VERSION ); if( !version ) { return; } // Parse string ptr = (GLubyte*) version; for( _major = 0; *ptr >= '0' && *ptr <= '9'; ptr ++ ) { _major = 10*_major + (*ptr - '0'); } if( *ptr == '.' ) { ptr ++; for( _minor = 0; *ptr >= '0' && *ptr <= '9'; ptr ++ ) { _minor = 10*_minor + (*ptr - '0'); } if( *ptr == '.' ) { ptr ++; for( _rev = 0; *ptr >= '0' && *ptr <= '9'; ptr ++ ) { _rev = 10*_rev + (*ptr - '0'); } } } // Return parsed values if( major != NULL ) { *major = _major; } if( minor != NULL ) { *minor = _minor; } if( rev != NULL ) { *rev = _rev; } }