Full-screen games on a Retina Macbook Pro sometimes start strangely

Solution 1:

Thanks @eternus for answering, but my issue was that for some reason, my computer doesn't always switch to the discrete card once I open a game. Restarting usually fixes the problem, but a more thorough way to solve it is to get this app called gfxCardStatus, which allows you to specify which card you'd like to use. You choose the "Discrete only" option before running a game, and it should work fine. Here's what it looks like running in your task bar:

Solution 2:

You can fix this with no extra apps by disabling "Automatic Graphics Switching" under the Energy Saver section of System Preferences.

Solution 3:

It sounds like the game isn't optimized for Retina Display, though it's odd that it sometimes works and sometimes not. Try setting the .app to open in Low Resolution. You can do this by right-clicking the .app file > Get Info and check "Low Resolution" option under the General section.