RE: skipdraw from Eric Ball WAS: [stella] Finally underway: 2600Cookbook

Subject: RE: skipdraw from Eric Ball WAS: [stella] Finally underway: 2600Cookbook
From: "Erik Mooney" <erik@xxxxxxxxxx>
Date: Tue, 13 Apr 2004 10:22:31 -0500
KirkIsrael@xxxxxxxxxxxxx wrote:

> -exact horizontal positioning
> -indirect referencing for changing player graphics

This post gives a detailed explanation of exact horizontal positioning:

http://www.biglist.com/lists/stella/archives/199804/msg00170.html

Unfortunately, I discovered while writing RRampage that that
table has been wrong all along!  It doesn't work for an X position
of 7 or lower, because then the RESP0 completes at cycle 21, which
is still during HBLANK and so the object ends up in the wrong 
place.  (INV doesn't position any objects there so I never
noticed it.)

I have a version now that corrects that; the code also needs to
burn two extra cycles (NOP) before starting the delay loop.
I'll write this up later tonight to send to you, Kirk.  I can do 
a decent writeup of indirect-indexed graphics loading as well.
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