Saturday, 21 June 2014


I've had enough of hardware bashing for one day so tonight I started work on writing a C implementation of Apple II Lode Runner. There will be a hardware abstraction layer so that it is as portable as possible. I'm hoping I'll be able to port this to the Amiga or the Neo Geo without going through the pain of producing a 68K assembler translation.

The purpose is two-fold; to assist in the understanding and documentation of the original implementation (specifically the guard AI) and also facilitate ease of porting to more platforms.

To this end, the aim (again) is to preserve the style and nuances of the original code as far as possible, to the extent that it doesn't cloud the more interesting aspects, such as the AI. For instance I'll be retaining the bulk of the zero-page variables - although some data types will be changed, such as the score, which will go from four (4) BCD bytes to a single uint32_t. Similarly the rendering routines are considered to be uninteresting and in any case will be abstracted away from the main code.

Thus far I have it displaying the title screen, waiting for a key, and then starting to render the game screen for the demo. All this in about an hour; a bit faster than writing - or even porting - assembler code!

No comments:

Post a Comment