Super Xevious coming soon!

I've fixed one bug in the Amiga port (it was copied from my code) but I haven't been working on the next beta or the Amiga version as I should be... instead I've been distracted by the possibilty of adding Super Xevious to the transcode.

To this end, I've been going through the MAIN CPU and naming all the labels; IOW a complete RE except for the comments. And I finished this morning.

In a nutshell, the Super Xevious MAIN CPU code is a super-set of the Xevious code. The only real differences are the addition of six (6) object handlers at the end of the object handler table and the table of flying enemy types. And of course slight changes to the title screen and copyright messages. Some of the copy protection code has been sacrificed for the new object handlers.

Adding the additional object handlers wouldn't affect the Xevious gameplay in any way, so there wouldn't be any need to #define those out for a Xevious build. That just leaves the title, copyright and flying enemy table, which would be trivial.

And as mentioned previously, the SUB CPU code would just require those three (3) different lookup-tables to be selected for each respective build.

Almost too easy!

UPDATE: I've updated my map parsing tool (it's more accurate now and handles the new objects) and have confirmed that none of the previously unused add-object functions in the SUB CPU, and none of the previously unused object handlers in the MAIN CPU are being used by Super Xevious. Thus additions are purely the six new objects. In fact, much of the map, and object counts throughout the map, are very similar to Xevious - it really doesn't play that differently, except perhaps the difficulty level in the new flying enemy table.

I also looked at the execution flow of the original vs the transcode (the context of the VBLANK interrupt and graphics hardware accesses) in light of the 'shaking ground objects' in the Amiga port. TBH I can't really explain it atm, without suggesting that the Amiga is eg. simply updating the scrolling outside the blanking period?!? I need to discuss further with jotd...