Shadow Dancer/Notes

The following article is a Notes Page for Shadow Dancer.

This page contains notes about an attempt to hack the game, replacing graphics and maps to make the game similar to the arcade classic Shinobi.

I intend to study :

• how to edit sprites graphical data (mostly done)
• how to alter character behaviour (to do)
• how to edit sprites collision boxes (to do)
• how to edit tiles and maps (mostly done)
• how to edit collisions with maps (in progress)

The terminology used here is mostly borrowed from the document entitled Sega Genesis VDP documentation by Charles MacDonald (available on RHDN), refered by [CMD] :

• a pattern is a 8*8 16 colors tile, aimed to be loaded in VRAM (see [CMD])
• a sprite is made from 1*1 to 4*4 contiguous pattern(s), with palette, flipping and link attributes (see [CMD])
• a "multisprite" is made from several sprites, with position relatives to an origin (not in [CMD])
• a ROM address is between 00000 and 80000, a RAM address between FF0000 and FFFFFF

Sprites

This section describes how the Joe Musashi and the ennemies "sprites" (in fact, multisprites) are loaded.

Joe Musashi

Patterns

A whole set of patterns is loaded at once at RAM address FF9300. Only relevant patterns will later be loaded in VRAM. The set is Nemesis-compressed at ROM address 23540. Nemesis compression is a well-known compression scheme which is described here.