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'''JD:''' The problem with using the high-resolution graphics mode is not only being unfamiliar with it, but also understanding the constraints. First, it uses up so much of the VDP RAM that there's only 2,000 bytes of RAM free for the programmer to use. Also, at the time, we felt we could not use sprite automotion in this mode. The problem we had was that the scroll used up so much processor time that in order for me to move sprites on the screen, I had to use automotion. If I were to move the sprites pixel by pixel as I did in [[Munch Man]] and [[Car Wars]], it would be way too slow. I had to go to automotion or else the project would have been killed.
At this point, Paul remembered that the 99/4A's newer architecture would allow us to do our own interrupt processing; this meant that we could do our own sprite automotion it we relocated the sprite attribute table from where it normally was to the unused area of high-VDP RAM that I mentioned earlier.
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