[atari7800] Re: [personal] Re: Determining zone height?

> I was under the assumption that when you move your sprites vertically
> you had to do this anyway? How do you achieve smooth vertical motion
> without the sprite overlapping zones?

For vertical motion a single sprite will be in two (or more) zones.  But if
the sprite is taller than holey DMA (like I did with SpaceWar! 7800, where
the zones & holey DMA are 8 lines, but the ships are 16 lines) then you end
up with:
DLL lines 23-16    top half
DLL lines 15-8    top half & bottom half
DLL lines 0-7    bottom half

And with wrap around, that doubles again:
DLL lines 23-16    top half right side, top half left side
DLL lines 15-8    top half right side, top half left side, bottom half right
side, bottom half left side
DLL lines 0-7    bottom half right side, bottom half left side

It just occurred to me that if your sprite is taller than 16 lines then it
might be easier to not use holey DMA and just pad out everything with zone
height - 1 blank lines top & bottom.

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