Hey, I know this is really retarded, but I'm having trouble doing
a single digit scoring routing...
I have the digits 0-9 like this
(upsidedown)
Score0Graphic
.byte #%00111100
.byte #%01000010
.byte #%01000010
.byte #%01000010
.byte #%00111100
Score1Graphic
.byte #%00111110
.byte #%00001000
.byte #%00001000
.byte #%00101000
.byte #%00011000
I know 5 is kind of an odd number,
I tried for 4 but couldn't make it look good, and it seems wasteful
to pad it to 8
I decided that the score display was going to be a seperate kernal,
above the main action. But my overwhelming ignorance about memory
deferencing is killing me here.
I think the basic idea is pretty simple:
for each scanline, the piece of score to display is at
Y (holding scanline) + (5 * playerscore) + startofscoresinmemory
(hmm, actually maybe I should compute
(5 * playerscore) + startofscoresinmemory
during the VBLANK and then just add the scanline to that?
Anyway, this is the bit I came up with:
ScoreDisplayLoop
LDA p0score ;accumulator = score
ROL ;accumulator = score * 2
ROL ;accumulator = score * 4
CLC
ADC p0score ;accumulator = (score * 4) + score = score * 5
CLC
ADC Score0Graphic
STA GRP0
;...P1 etc goes here, along with two WSYNCs
DEY
BNE ScoreDisplayLoop
Ugh, I know that's pretty badly broken, I'm not derefrencing right
at all. Plus, I probably really should compute most of that before
hand, and then look to that computed value plus the scan line count...
Also, 2 more questions:
* what emulator supports showing the scan line count? how do you do it?
* how can I find out how much of the 4K I'm actually using?
Anyway, http://alienbill.com/joustpong/ has the result of today's
labor...it's pretty cool, I made the 2nd player controlled by the
computer, so it's actually cool to play as a game right now.
Thanks for all your help!
-Kirk
--
KirkIsrael@xxxxxxxxxxxxx http://kisrael.com
"Oh, you hate your job? Why didn't you say so? There's a support group for
that. It's called EVERYBODY, and they meet at the bar." --Drew Carey
----------------------------------------------------------------------------------------------
Archives (includes files) at http://www.biglist.com/lists/stella/archives/
Unsub & more at http://www.biglist.com/lists/stella/
