Friday, 16 May 2008
I've unraveled some of the last few mysteries of Namco's NA1 system hardware. The "rotate and zoom" layer so far appears to only be used by a single game, Emeralda.
The single oddest feature I encountered was a spriteram attribute that causes the palette to be interpretted in a radically different manner. This fixes the onscreen score text in Emeralda, which, now that it is correctly emulated, features color gradients and anti-aliasing. This same effect could have been accomplished more-or-less equivalently with the standard -rrrrrgggggbbbbb palette. I'm baffled as to why hardware designers and software would have implemented the feature in such a roundabout manner. A screenshot featuring the corrected colors is featured below.