Re: Aw: Re: [stella] need 16-bit math for JoustPong?

Subject: Re: Aw: Re: [stella] need 16-bit math for JoustPong?
From: KirkIsrael@xxxxxxxxxxxxx
Date: 5 Feb 2004 16:58:38 -0000
> Hi there!
> > David Galloway wrote:
> > > I think it would be good coding practice to keep the low byte first 
> > > (little endian) ; addresses on the 6507 are low byte, high byte. example 
> > > lda (zp),y  And keeping your 16 bit math routines the same can possibly 
> > > save space and prevent bugs.
> > > Also, since it is standard practice, someone can more easily read your 
> > > code and you can read others code.
> > This is all true, but not always. E.g. separting the integer and fractional
> > parts allows looping over the integer parts for horizontal positioning,
> > using the same index for reading the position (xPos,X) and writing to 
> > the hardware registers (RESP0,X; HMP0,X). Else you would need two
> > separate indexes.
> I think one should clearly distinguish between "Fractional Adding" and "16 Bit Math" :-)

Yeah, I've kind of lost the thread of this conversation.

But after a stern talking to from Andrew Davies ;-) I'm renouncing
my heretical "big endian" ways, though high byte last still seems 
awfully weird to me.

So I gotta switch the order of my 16 bit storing bytes,
get the bugs out of my floor rebound routine, than looking
into adding fractional positioning for the ball...then look
into final debugging of the wall stuff, and some misc. other

I'd really like to be done by the begining of March, launch
at phillyclassic

"If you feel it, but it isn't right, don't do it and don't 
 believe it. We can be better than natural -- we're human."--Penn Jillette

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