How do I take screenshots?
The default screenshot control binding is f12.
Screenshots may also be taken by bringing down the console and entering "screenshot" (though, using this method the console will obscure the screen).
Screenshots are saved as PNG images in the runtime folder named after the game they were taken in. For instance a screenshot taken in Final Doom: Plutonia will be called doom2-plut-000.png, where "000" will increase by one with each screenshot.