As we wizz through the half-way stage there has been some progress.
I have written code to handle a collection of upto 256 8×8 tiles. I also have structures that arrange tiles into upto 255 rooms of 4×3 tiles each and routines that can draw a room and tell me what room I’ll end up in if I leave the current one in any direction. This means I have a complete map of 30 rooms at the moment, interconnected.
Next up I have some routines that can handle my player sprite. I can read the screen memory below the sprite (so I can put it back later), draw a sprite and then put the ground back (told you I’d need it later).
The little GIF is a walk through of part of the cellar (click on it to see the animated version).
Currently there is no collision detection, baddies, goodies and there is no timing and video blanking type work. But, not bad so far.