RE: [stella] Ms. Pac Man, Mr. Do, striped playfields, and one-line kernels

["Lee Fastenau" <stella@xxxxxxxxxxxxxxx>]

> So you have 24 cycles for skipDraw, which is more than enough. :-)

Thomas,
I was really looking forward to saving 250 bytes of ROM by incorporating
skipdraw, but it's not going to be nearly as big a savings as I'd hoped.  I
rearranged all 6 parts of my unrolled kernel to give me at least 23
consecutive cycles in each part for skipdraw.  Everything was great until I
switched to two-player mode and noticed that my side-wall color was bleeding
slightly into the top-right paddle.  I tried all sorts of rearranging and
ended up making another design decision: visually detatch two-player paddles
from the side walls.  This required me to unroll a seventh part of the
kernel... and it's far from perfect.  While the playfield is suppressed
between the top paddle and the side walls, it is simply colored to look like
the background for the bottom paddle.

So far, I've added around 100 bytes to my kernel and have made an
unacceptable compromise to the design.  (One paddle is closer to the bricks
than the other in a two player game, although it doesn't visually appear
so...)  If I run into _severe_ ROM space problems, I'll probably refer to
the work I've done here, but I'm going back to my page-size sprite for now.

Still, what an awesome learning experience.  And now I can count cycles in
my sleep! :)

Thank you for your sharing your knowledge and experience.

> Have fun!
> Thomas

I attached the source and binaries for the "color bleed" and the
"compromise" versions of Reflex.  Switch to two-player mode to see it...

-Lee

Attachment: reflex64.asm
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Attachment: reflex67.asm
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Attachment: reflex64.bin
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Attachment: reflex67.bin
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