WIP, gameplay complete
The basic gameplay is now complete. Press the button and push the joystick right or left to dig. Comments, opinions & suggestions welcome.I also managed to trip myself up quite nicely as I was adding the new sprites. Basically I forgot that any access to $1FF8 aka $FFF8 on a SuperCharger will trigger a bankswitch. And I stuck the sprite data after the playfield bitmaps, which just happened to be on page $1F00. So the game would work quite nicely until it did the right blit and accessed $1FF8. Kaboom! This is one place where z26's trace log somes in handy since I had no idea what had happened. So I let z26 log until the game dies, then had a look at the last few frames in the trace file to try and figure out where things went amok. At first, I thought it was a rogue SC write which had trashed the code somehow. But later the real reason hit me.I was going to simply re-arrange the code & data to move the playfield bitmaps. But then I remembered my gold blit routine relies on the playfield bitmaps being at the end of the address space to simplify one of the loop tests. Sigh. So I've just temporarily shifted the offending spite to a free chunk of ROM. (I've just about used all 4K, although I'd always planned to use all 6K.)I think my next target is to rework the kernel to use a reflected playfield and do some other stuff to stabilize the level data format.(2005/12/15 - fixed some minor sprite glitches)
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