More RE and more transcoding!

Some progress in small chunks over the weekend. I've now finished all the (23) ground-based objects, and moving on to the flying objects that are explicitly defined in the map data. These objects don't vary with the difficulty/AI level. So far I have done a lone Kapi, Terrazi, Torkan and currently working on the Garu Zakato (big exploding bomb in Area 9).

Garu Zakato WIP

I've been forced to do more of the RE in order to complete the implementation of the last few objects. So much of the code has been understood now, the last few routines are falling into place fairly easily. For instance the Garu Zakato loops through the bullet objects looking for 16 idle bullets, and initialises them in turn with every 2nd angle in the firing angle table; something I had no idea about until just a few days ago. It also creates a further 4 (flying) objects in the table - objects I had been unable to identify until now.

During my testing I've finally seen evidence of the Neo Geo's 96 sprites-per-scanline limit being exceeded. It's a bit of a false alarm atm, because I'm not optimising sprite usage, and the skipping of areas that produces the "bullet-hell" effect isn't realistic. The good news is that it will be very easy to identify if/when it happens, as the last sprites in the priority - the first ones that will not be rendered - are what I call the "visible display masking sprites" at top and bottom of screen, and mask the 'bouncing' effect of the scrolling background layer.