Retina display core graphics font quality

Question

Trying to understand why am I getting low quality drawing with CGContextShowTextAtPoint? See attached image:

The letter "W" is drawn using CGContextShowTextAtPoint on a CALayer and looks very pixelized. The button next to it is a standard button and looks high res as expected. I would like to get the text drawing to be hi-res.

Answer 1

By default, your CALayer is not rendering its Quartz content at the higher resolution of the Retina display screen. You can enable this using code like the following:

if ([layer respondsToSelector:@selector(setContentsScale:)])
{
    layer.contentsScale = [[UIScreen mainScreen] scale];
}

This will affect not just text rendering, but all of your Quartz drawing within CALayers, so you'll need to do this for all of your layers with custom Quartz content.