C++ (Cpp) CL_OpenGLWindowDescription::get_allow_lower_versions Examples

Example #1

File: opengl_window_provider_glx.cpp Project: Zenol/clanlib-2.4

GLXContext CL_OpenGLWindowProvider_GLX::create_context_glx_1_2(const CL_OpenGLWindowDescription &gl_desc, GLXContext shared_context)
{
	if (gl_desc.get_allow_lower_versions() == false)
		throw CL_Exception("GLX 1.2 does not support opengl version selection.");

	GLXContext context;
	context = glx.glXCreateContext(x11_window.get_display(), opengl_visual_info, shared_context, GL_TRUE);
	if(context == NULL)
		throw CL_Exception("glXCreateContext failed");

	return context;
}

Example #2

File: opengl_window_provider_glx.cpp Project: Zenol/clanlib-2.4

GLXContext CL_OpenGLWindowProvider_GLX::create_context_glx_1_3(const CL_OpenGLWindowDescription &gl_desc, GLXContext shared_context)
{
	GLXContext context;

	context = glx.glXCreateNewContext(x11_window.get_display(), fbconfig, GLX_RGBA_TYPE, shared_context, True);
	if(context == NULL)
		throw CL_Exception("glXCreateContext failed");
	
	ptr_glXCreateContextAttribs glXCreateContextAttribs = NULL;

	if (is_glx_extension_supported("GLX_ARB_create_context"))
	{
		if (glx.glXGetProcAddressARB)
			glXCreateContextAttribs = (ptr_glXCreateContextAttribs) glx.glXGetProcAddressARB((GLubyte*) "glXCreateContextAttribsARB");
		if (glx.glXGetProcAddress)
			glXCreateContextAttribs = (ptr_glXCreateContextAttribs) glx.glXGetProcAddress((GLubyte*) "glXCreateContextAttribsARB");
	}


	if (glXCreateContextAttribs)
	{
		// Install an X error handler so the application won't exit if GL 3.0 context allocation fails.
		//
		// Note this error handler is global.  All display connections in all threads
		// of a process use the same error handler, so be sure to guard against other
		// threads issuing X commands while this code is running.
		int (*oldHandler)(Display*, XErrorEvent*) = XSetErrorHandler(&cl_ctxErrorHandler);
	  
		GLXContext context_gl3 = 0;

		int gl_major = gl_desc.get_version_major();
		int gl_minor = gl_desc.get_version_minor();
		if (gl_desc.get_allow_lower_versions() == false)
		{
			context_gl3 = create_context_glx_1_3_helper(shared_context, gl_major, gl_minor, gl_desc, glXCreateContextAttribs);
	
			if (!context_gl3)
				throw CL_Exception(cl_format("This application requires OpenGL %1.%2 or above. Try updating your drivers, or upgrade to a newer graphics card.",  gl_major, gl_minor));
		}
		else
		{
			static const char opengl_version_list[] = 
			{
				// Clanlib supported version pairs
				4,1,
				4,0,
				3,3,
				3,2,
				3,1,
				3,0,
				0,0,	// End of list
			};

			const char *opengl_version_list_ptr = opengl_version_list;
			do
			{
				int major = *(opengl_version_list_ptr++);
				if (major == 0)
					break;
					
				int minor = *(opengl_version_list_ptr++);

				// Find the appropriate version in the list
				if (major > gl_major)
					continue;

				if (major == gl_major)
				{
					if (minor > gl_minor)
						continue;	
				}

				context_gl3 = create_context_glx_1_3_helper(shared_context, gl_major, gl_minor, gl_desc, glXCreateContextAttribs);

			}while(!context_gl3);
		}
		
		// Restore the original error handler
		XSetErrorHandler( oldHandler );		
		
		if (context_gl3)
		{
			glx.glXDestroyContext(x11_window.get_display(), context);
			context = context_gl3;
		}
	}
	return context;
}