Adding retina display support results in OpenGL ES not drawing anything
ios, ios-simulator, iphone, opengl-es, retina-display
Solution
I was facing the same problem. The call to `eaglLayer.contentsScale = [[UIScreen mainScreen] scale];` is not needed and you have to multiply the frame dimensions with the screen scale. So the solution for your problem would be:
CGFloat screenScale = [UIScreen mainScreen].scale;
glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH_COMPONENT16, CGRectGetWidth(self.bounds) * screenScale, CGRectGetHeight(self.bounds) * screenScale);
Problem
I have an app that draws a scene in OpenGL ES 2.0. Everything renders correctly in the iPhone and iPad simulators, as well as on real devices, so long as I don't attempt to make use of the retina display. Retina devices still draw, but with the same resolution as older devices. On new devices, I get only a black screen. On the retina simulators, I get a pink screen. The program won't even make use of the value I set with glClearColor(); I can correctly set the scale factor for the device with the following code: ``` _eaglLayer = (CAEAGLLayer *)self.layer; _eaglLayer.opaque = YES; self.contentScaleFactor = [[UIScreen mainScreen] scale]; _eaglLayer.contentsScale = [[UIScreen mainScreen] scale]; ``` And I can correctly create a render buffer here: ``` glGenRenderbuffers(1, &_depthRenderBuffer); glBindRenderbuffer(GL_RENDERBUFFER, _depthRenderBuffer); glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH_COMPONENT16, self.frame.size.width, self.frame.size.height); //Context is an instance of EAGLContext [_context renderbufferStorage:GL_RENDERBUFFER fromDrawable:_eaglLayer]; ``` I set the size of the viewport as follows: ``` glGetRenderbufferParameteriv(GL_RENDERBUFFER, GL_RENDERBUFFER_WIDTH, &_backingWidth); glGetRenderbufferParameteriv(GL_RENDERBUFFER, GL_RENDERBUFFER_HEIGHT, &_backingHeight); ... glViewport(0, 0, _backingWidth, _backingHeight); ``` All of this code works on older devices, and it works flawlessly if I comment out the lines: ``` self.contentScaleFactor = [[UIScreen mainScreen] scale]; _eaglLayer.contentsScale = [[UIScreen mainScreen] scale]; ``` I've logged the scale as the view loads, and it correctly sets the value to 2.0 on retina devices or 1.0 on older devices. I've tried a number of different solutions and methods of setting the scale factor, but to no avail. I know there's something I'm just not seeing, but I can't find it. Suggestions?