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9 - A Quick Flash
One final point about performance becomes clear when you play with the program - as you speed up the drawing, you'll see the line edges blurring as it rotates. On my ebm, the line updates about 25 times a second, but the fuzziness makes for an unimpressive display. What this means is that even if we coded at assembly language level or otherwise tried to bypassed all the extra overhead to 'roll our own' code, we would still end up bumping up against the limitations of the display.LCDs have a latency time, and there is nothing that can be done about that. Instead of worrying overmuch about speed issues, we need to concentrate on perception, providing the illusion of speed. For example, rather than updating the line 25 times a second by one degree at a time, why not update five times a second, five degrees at a time? Less processing is needed, yet the user will still get the illusion of motion without the blurring. This and other perceptual tricks can give an illusion of speed to your program without unreasonable programming or processing effort.
This all-too-brief overview of ebm drawing shows that game programmers can rest assured - the lower levels of the OS needn't be plumbed to write quality games. Care in coding, working with the ebm's drawing methods, and taking into account the LCD screen can result in very playable games without sacrificing power or speed.
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