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In keeping with its original purpose as a graphics language, Zgrass included numerous commands for simple drawing. Zgrass's coordinate system had one point for each pixel in the high-resolution mode of Nutting's graphics chip, giving a 320×202 grid. The Astrocade, by design, could only use that chip's low-resolution mode, a 160×101 display. To avoid potential mapping problems, the coordinate space's zero point was placed in the center of the screen. −160 to 160 were valid X locations, and -101 to 101 valid Y locations. For use on the Astrocade you used the positive locations only, whereas on the UV-1 the entire space was available.
Zgrass added a fairly complete set of array functions, as arrays are widely used in graphics. This included the ability to "capture" parts of the display into an array as a [[bitmap]], which could then be manipulated as any other graphic item. This allowed Zgrass to include sprite-like functionality in the language, something the Nutting hardware did not directly include. Another feature the Astrocade did not include was the ability to process arrays with any reasonable speed, so the UV-1 included the Zilog supplied [[floating
Zgrass included three priorities (called ''levels'') that allowed macros to be run normally, or in "foreground" or "background" levels. This added a simple form of [[computer multitasking|multitasking]] which was tremendously useful in an animation-oriented language. Game authors could place joystick-reading routines in a macro set to run in the background, and then the joystick would be read automatically whenever the current drawing macro completed. Functions placed in the foreground ran before either, and was often used for timers and other "low latency" needs. Zgrass included a <code>TIMEOUT</code> function that would call macros on a timed basis, making the implementation of timers very easy.
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