Re: [stella] Sprite kernel (was: Distella --> DAsm problem)

Subject: Re: [stella] Sprite kernel (was: Distella --> DAsm problem)
From: emooney@xxxxxxxxxxxxxxxx (Erik Mooney)
Date: Sat, 22 Aug 1998 21:17:48 GMT
>Sorry, I assumed that there are more people familiar with just emulators 
>than assembly itself on the list.  I actually debated what to call it for 
>a while, and finally figured that anyone who knew the code wouldn't have 
>any problem deciphering which one I meant (and I see you didn't! ;) .  
>I'll start calling it P0 now though.  No reason to go easy on the 

Well, in that context it was pretty simple to decipher :)  But if you start
doing stuff like "there's an explosion when player 1 gets hit by missile
1", it can get mixed up.

>>This whole section is a little messy, but there isn't an easy way to clean
>>it up.. I'd guess that in a proper source listing, it'd be a little more
>>spread out and labeled better.
>Well, remember I'm commenting the code as I make it on my Mac, then 
>assembling it with "RAsm" and then dissembling it with Distella and 
>"re-commenting" it before send it on to the list.  Since I comment like 
>crazy, I think it's actually easier to read this less-commented code.
>How do you mean "spread out"?  Just the spacing as a text file?

I meant both the code (it was pretty spaghetti) and the spacing.  I might
have missed something, but is there any particular reason you can't post
the original code instead of the diassembled/reassembled version?

>>I'd suggest changing the kernel so that the same
>>WSYNC counts off every line of screen, as follows:...
>>This is a decent amount more streamlined and flexible.  Much easier to add
>>more objects, and it's less prone to error - 
>Yes, it is.  I'm afraid I wasn't really offering streamlined code.  As I 
>see it, I'm going to have to have code that deals with PF, P0, and M0 
>updates all in one scan line followed by PF, P1, and M1 updates the next, 
>so I've been in a "substitute extra code to save cycles" mindset.  That's 
>my excuse, anyway!  ;)

I wasn't expecting you to offer streamlined code :)  I'm just tryin' ta
help you take the next step, and maybe save you a bit of time before you
went and wound up with code that counted off till P0, unless P1 was higher
on the screen, in which case it would count off till P1, then it draws P1
and counts off to P0, unless P0 is on the same scanlines as P1, in which
case it jumps over to this whole other section over here, etc. :)

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