cpp_query.txt

来自「ROBOCUP 仿真3D server 源码」· 文本 代码 · 共 57 行

static bool TestExtensionString(const char *name, const char *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.
	*/
    const char *start = extensions;
    char *where, *terminator;
    
    where = strchr(name, ' ');
    if (where || *name == '\0')
        return false;
        
    for (;;)
    {
        where = strstr((const char *) start, name);
        if (!where)
            break;
        terminator = where + strlen(name);
        if (where == start || *(where - 1) == ' ')
            if (*terminator == ' ' || *terminator == '\0')
                return true;
        start = terminator;
    }
    return false;
}

// returns true if the extension is available
bool GLExtensionReg::QueryGLExtension(const char *name)
{
    const char *extensions = NULL;
	/*	extension names should not have spaces.	*/
    extensions = (const char*)glGetString(GL_EXTENSIONS);

	return TestExtensionString(name, extensions);
}

#if defined(_WIN32)
// returns true if the extension is available
bool GLExtensionReg::QueryWGLExtension(const char *name)
{
    const char *extensions = NULL;

    if ((wglGetExtensionsStringARB == NULL) || (mHDC == 0))
        if (wglGetExtensionsStringEXT == NULL)
            return false;
        else
            extensions = (const char*) wglGetExtensionsStringEXT();
    else
        extensions = (const char*) wglGetExtensionsStringARB(_dc);
        
 	return TestExtensionString(name, extensions);
}
#endif //_WIN32