I'm having fun with the C64 just now while Luca gathers together some sprites for me to use, but I've hit my first snag.... The MCM on the plus4 uses differnt bits than the C64! Damn. So, I've done a bit flipper to swap bits $01 and $10. This lets the colour RAM on the C64 do the bright colour (since in MCM on the C64 you only have a choice of 8), and the 2 full colour registers then make up the rest... This will work fine for the game graphics, but......... The panel has some HiRes graphics in it...Damn, damn.....
So looks like I'll have to do a character index and tell it the ones I WANT to swap...bugger. However, once thats done it should just be a matter of importing Plus4 graphics and using them directly! Initally I'll do a port routine for the Plus4 sprites as well, then I'll get them resized. The C64 sprites are 24x21 (or 12x21 in MCM), while the Plus4 ones are 16x16 so there quite a bit of extra space there! The reason for the odd sizes is simpky that it lets the C64 have a sprite every 64 bytes, making 256 in a VIC bank.
I think I can get the whole thing up and running (without sprites) pretty quickly, then I'll need to get a multiplexor going... and then that "should" be it! :)
(in theory....) Imagine doing a "dual" retro release!! How cool is that!!! Now... if only I could persuade Russell (Kay - Lemmings PC programmer) to write the spectrum one...Mmmmm.... That WOULD be a complete rewrite though...
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