Re: [stella] Do the math

Subject: Re: [stella] Do the math
From: Manuel Rotschkar <cybergoth@xxxxxxxx>
Date: Thu, 06 May 2004 08:08:36 +0200
Hi there!

	LDA #212
	STA xdelay
	LDA xpos
	ADC #02
	DEC xdelay
	SBC #$03
	BCS DivideBy3

This version is MUCH slower and can eat up a whole extra scanline depending on the value of xpos.

Way cool, I might even switch to this, as the main reason for coding this formula was ROM shortage :-)
(the code saved me a 150 bytes lookup table...)

Very handy if you need to burn up those pesky, unwanted free cycles.

Funny thing is, I was very concerned about the cycles this would eat up, especially when it was possibly called 4 times per frame with xpos values up to 140.

That was when I discovered to my own surprise that Seawolf didn't use any Overscan time at all so far... ;-)

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