Use "A", "S", "D", "W" KEYS to move your player. (these keys are changeable in the options menu). Use THE MOUSE to aim and click MOUSE BUTTON to shoot your weapon. Change weapons with the MOUSEWHEEL. Destroy all enemy units to progress through snow, jungle, canyon lands and lab levels... featuring over 30 weapons

GameCanvas is a Canvas with additional capabilities; it provides methods for immediate painting and for examining the state of the device keys. These new methods make it possible to enclose all of a game's functionality in a single loop, under control of a single thread. To see why this is attractive, think about how you would implement a typical game using Canvas:
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