www.pudn.com > simple_fragment_program2.zip > glh_extensions.h
// Comments: // // The trick with GLH_EXT_SINGLE_FILE is that you need to have it defined in // exactly one cpp file because it piggy-backs the function implementations in // the header. You don't want multiple implementations defined or the linker // gets mad, but one file must have the implementations in it or the linker // gets mad for different reasons. // // The goal was to avoid having this helper require a separate cpp file. One // thing you could do is just have a glh_extensions.cpp that did // // #define GLH_EXT_SINGLE_FILE // #include// // and make it the only file that ever defines GLH_EXT_SINGLE_FILE. #ifndef GLH_EXTENSIONS #define GLH_EXTENSIONS #include #include #include #if defined(WIN32) # include #endif #ifdef MACOS #include #else #include #endif #ifdef WIN32 # include #endif #define CHECK_MEMORY(ptr) \ if (NULL == ptr) { \ printf("Error allocating memory in file %s, line %d\n", __FILE__, __LINE__); \ exit(-1); \ } #ifdef GLH_EXT_SINGLE_FILE # define GLH_EXTENSIONS_SINGLE_FILE // have to do this because glh_genext.h unsets GLH_EXT_SINGLE_FILE #endif #if (defined(WIN32) || defined(UNIX)) #include "glh_genext.h" #elif defined(MACOS) #include #else #include #endif #ifdef __cplusplus extern "C" { #endif #ifdef GLH_EXTENSIONS_SINGLE_FILE static char *unsupportedExts = NULL; static char *sysExts = NULL; #ifndef GL_SHADER_CONSISTENT_NV #define GL_SHADER_CONSISTENT_NV 0x86DD #endif #ifndef GL_TEXTURE_SHADER_NV #define GL_TEXTURE_SHADER_NV 0x86DE #endif #ifndef GL_SHADER_OPERATION_NV #define GL_SHADER_OPERATION_NV 0x86DF #endif static int ExtensionExists(const char* extName, const char* sysExts) { char *padExtName = (char*)malloc(strlen(extName) + 2); strcat(strcpy(padExtName, extName), " "); if (0 == strcmp(extName, "GL_VERSION_1_2")) { const char *version = (const char*)glGetString(GL_VERSION); if (strstr(version, "1.0") == version || strstr(version, "1.1") == version) { return GL_FALSE; } else { return GL_TRUE; } } if (0 == strcmp(extName, "GL_VERSION_1_3")) { const char *version = (const char*)glGetString(GL_VERSION); if (strstr(version, "1.0") == version || strstr(version, "1.1") == version || strstr(version, "1.2") == version) { return GL_FALSE; } else { return GL_TRUE; } } if (0 == strcmp(extName, "GL_VERSION_1_4")) { const char *version = (const char*)glGetString(GL_VERSION); if (strstr(version, "1.0") == version || strstr(version, "1.1") == version || strstr(version, "1.2") == version || strstr(version, "1.3") == version) { return GL_FALSE; } else { return GL_TRUE; } } if (0 == strcmp(extName, "GL_VERSION_1_5")) { const char *version = (const char*)glGetString(GL_VERSION); if (strstr(version, "1.0") == version || strstr(version, "1.1") == version || strstr(version, "1.2") == version || strstr(version, "1.3") == version || strstr(version, "1.4") == version) { return GL_FALSE; } else { return GL_TRUE; } } if (strstr(sysExts, padExtName)) { free(padExtName); return GL_TRUE; } else { free(padExtName); return GL_FALSE; } } static const char* EatWhiteSpace(const char *str) { for (; *str && (' ' == *str || '\t' == *str || '\n' == *str); str++); return str; } static const char* EatNonWhiteSpace(const char *str) { for (; *str && (' ' != *str && '\t' != *str && '\n' != *str); str++); return str; } int glh_init_extensions(const char *origReqExts) { // Length of requested extensions string size_t reqExtsLen; char *reqExts; // Ptr for individual extensions within reqExts char *reqExt; int success = GL_TRUE; // build space-padded extension string if (NULL == sysExts) { const char *extensions = (const char*)glGetString(GL_EXTENSIONS); size_t sysExtsLen = strlen(extensions); const char *winsys_extensions = ""; size_t winsysExtsLen = 0; #if defined(WIN32) { PFNWGLGETEXTENSIONSSTRINGARBPROC wglGetExtensionsStringARB = 0; wglGetExtensionsStringARB = (PFNWGLGETEXTENSIONSSTRINGARBPROC)wglGetProcAddress("wglGetExtensionsStringARB"); if(wglGetExtensionsStringARB) { winsys_extensions = wglGetExtensionsStringARB(wglGetCurrentDC()); winsysExtsLen = strlen(winsys_extensions); } } #elif defined(UNIX) { winsys_extensions = glXQueryExtensionsString (glXGetCurrentDisplay(),DefaultScreen(glXGetCurrentDisplay())) ; winsysExtsLen = strlen (winsys_extensions); } #endif // Add 2 bytes, one for padding space, one for terminating NULL sysExts = (char*)malloc(sysExtsLen + winsysExtsLen + 3); CHECK_MEMORY(sysExts); strcpy(sysExts, extensions); sysExts[sysExtsLen] = ' '; sysExts[sysExtsLen + 1] = 0; strcat(sysExts, winsys_extensions); sysExts[sysExtsLen + 1 + winsysExtsLen] = ' '; sysExts[sysExtsLen + 1 + winsysExtsLen + 1] = 0; } if (NULL == origReqExts) return GL_TRUE; reqExts = strdup(origReqExts); reqExtsLen = strlen(reqExts); if (NULL == unsupportedExts) { unsupportedExts = (char*)malloc(reqExtsLen + 2); } else if (reqExtsLen > strlen(unsupportedExts)) { unsupportedExts = (char*)realloc(unsupportedExts, reqExtsLen + 2); } CHECK_MEMORY(unsupportedExts); *unsupportedExts = 0; // Parse requested extension list for (reqExt = reqExts; (reqExt = (char*)EatWhiteSpace(reqExt)) && *reqExt; reqExt = (char*)EatNonWhiteSpace(reqExt)) { char *extEnd = (char*)EatNonWhiteSpace(reqExt); char saveChar = *extEnd; *extEnd = (char)0; #if (defined(WIN32) || defined(UNIX)) if (!ExtensionExists(reqExt, sysExts) || !glh_init_extension(reqExt)) { #elif defined(MACOS) if (!ExtensionExists(reqExt, sysExts)) { // don't try to get function pointers if on MacOS #endif // add reqExt to end of unsupportedExts strcat(unsupportedExts, reqExt); strcat(unsupportedExts, " "); success = GL_FALSE; } *extEnd = saveChar; } free(reqExts); return success; } const char* glh_get_unsupported_extensions() { return (const char*)unsupportedExts; } void glh_shutdown_extensions() { if (unsupportedExts) { free(unsupportedExts); unsupportedExts = NULL; } if (sysExts) { free(sysExts); sysExts = NULL; } } int glh_extension_supported(const char *extension) { static const GLubyte *extensions = NULL; const GLubyte *start; GLubyte *where, *terminator; // Extension names should not have spaces. where = (GLubyte *) strchr(extension, ' '); if (where || *extension == '\0') return 0; if (!extensions) extensions = glGetString(GL_EXTENSIONS); // 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; for (;;) { where = (GLubyte *) strstr((const char *) start, extension); if (!where) break; terminator = where + strlen(extension); if (where == start || *(where - 1) == ' ') { if (*terminator == ' ' || *terminator == '\0') { return 1; } } start = terminator; } return 0; } #else int glh_init_extensions(const char *origReqExts); const char* glh_get_unsupported_extensions(); void glh_shutdown_extensions(); int glh_extension_supported(const char *extension); #endif /* GLH_EXT_SINGLE_FILE */ #ifdef __cplusplus } #endif #endif /* GLH_EXTENSIONS */