[stella] one last 16 bit compare question

Subject: [stella] one last 16 bit compare question
From: KirkIsrael@xxxxxxxxxxxxx
Date: 9 Mar 2004 03:23:12 -0000

So I'm trying to wrap things up by Wednesday, a self-appointed
deadline that should give Al sufficient enough time to put my 
ROMly dream into silicon.  

I added in a pretty nifty 3...2...1 countdown to start each 
game, as well as randomly launching the ball left or right,
up or down (using the old "timer increments every frame, 
AND to get bit D0 and D1" trick)

So except for considering some AI improvements, I have one 
more improvement to make... Al pointed out that when the ball 
goes flat, it definately doesn't look quite as cool. So I think
along with a maximum vertical speed, I'd like to apply a minimum
vertical speed. Though I'm not sure what the best way of doing that 

For the maximum, I punted, and just look at the integer 
part of the 16 bit (8 bit int, 8 bit 'fractional'):


;keep ball speed in range
	LDA slowBallYSpeed+1
	BMI    BallSpeedLessThanMax
	BPL    BallSpeedGreaterThanMin
	STA    slowBallYSpeed+1

Is that right, to keep the speed 
between 1 255/256 and -1 255/256 ?  

What would the code to keep the absolute
value of the ball speed >=  #%00100000 ?

Should I do an AND $80 to see if it's negative,
and then just do a specific comparison
on the fractional byte?

Thanks, and any last minute suggestions for JoustPong

KirkIsrael@xxxxxxxxxxxxx    http://kisrael.com
 "Sometimes your shallowness is so thorough, it's almost like depth."--Daria

Archives (includes files) at http://www.biglist.com/lists/stella/archives/
Unsub & more at http://www.biglist.com/lists/stella/

Current Thread