Fantasia (Genesis)/ROM map

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This is a sub-page of Fantasia (Genesis).

Mickey sprites and animation

Animations Frames

Informations about Mickey animations frames are stored in a table of pointers at 0xd89a:

 00ff27ac ; 00: idle
 00ff26a4 ; 01: walk
 00ff26d8 ; 02: cast big spell
 00ff272c ; 03: jump
 00ff282c ; 04: ? (corrupted?)
 00ff272c ; 05: jump
 00ff272c ; 06: jump
 00ff272c ; 07: jump
 00ff272c ; 08: jump
 00ff272c ; 09: jump
 00ff272c ; 0a: jump
 00ff270c ; 0b: ? (corrupted?)
 00ff2780 ; 0c: cast small spell
 00ff2760 ; 0d: cast spell while jumping
 00ff27cc ; 0e: ? (corrupted?)
 00ff27ec ; 0f: turnover
 00ff280c ; 10: ? (corrupted?)
 00ff2858 ; 11: afraid of falling
 00ff2858 ; 12: afraid of falling
 00ff272c ; 13: jump

These pointers are in RAM, but the 0xff0000 - 0xff3fff area in RAM is a copy of the 0x7f000 - 0x7ffff area in ROM. So, for example, data about animation #00 can be found at ROM offset 0x7e7ac:

 0003 ; number of frames in the animation
 00000000 ; used for static sprites (GUI)
 0039 ; number of patterns for the whole animation
 0001CF2E ; pointer to patterns data
 0000 ; 
 0000 ; 
 0020 ; width of the sprite (used for hfliping)
 0028 ; height of the sprite
 0001CEF8 ; pointer to frame description of frame #0
 0001CF0A ; pointer to frame description of frame #1 
 0001CF1C ; pointer to frame description of frame #2

Patterns data located in ROM at offsets 0x18354, 0x1d95e, 0x1928e, 0x1c480 and 0x1cf2e are compressed with a RLE scheme described below. Otherwise, they are uncompressed.

Frame description have the following format:

 0002 ; nb of hardware sprites
 ;
 ; hardware sprite #1
 0018 ; dy (counted upwards)
 0f   ; size (0000HHVV)
 01   ; id of the hardware sprite 
 0000 ; offset to first pattern
 0000 ; dx
 ;
 ; hardware sprite #2
 0020 
 08
 02
 0010
 0000
 0002

Gfx Compression scheme

Compressed data is a stream of instruction code with variable arguments. Each instruction decompress into one pattern (32 bytes).

  • 00: end of the stream
  • 02: copy the 32 next bytes (i.e. pattern is not compressed)
  • 04: vertical RLE. The tile is built by columns (from top to bottom, then left to right). Each subsequent bytes is nnnnvvvv where n is the number of pixels and v their color index.
  • 06: same, but horizontal (pattern is built from left to right, then top to bottom)

Animation breakdown and timings

Offsets to animations breakdowns table is located at 0xd84a:

 0000d7e2 ; 00: idle
 0000d7ea ;
 0000d7f4 ;
 0000d7fe ;
 0000d800 ;
 0000d80c ;
 0000d80e ;
 0000d812 ;
 0000d814 ;
 0000d816 ;
 0000d818 ;
 0000d81e ;
 0000d826 ;
 0000d82e ;
 0000d836 ;
 0000d83e ;
 0000d846 ;
 0000d9b0 ;
 0000d9b8 ;
 0000d9c0 ;

For each animation, a sequence of frames (bytes) is given, terminated by a 0xff. Example for animation 0 (idle animation) at 0xd7e2:

 00 01 02 01 00 01 02 ff

The timings of animations are located in RAM, at 0xff042a. It is copied from ROM address 0x7c42a. Each entry is 2 bytes, the first is a counter (obviously 00 in the ROM data) and the second controls the duration of the animation. In particular, all frames in a given animation are displayed the same number of frames.

Note : the walking animation speed can change when acquirring speed and varies from 4 to 2. The speed is adjusted by the instruction at 0x2754.

 00/06 ; 00: idle animation plays at 60/6 = 10 fps
 00/04 ; 01: walking animation plays at 60/4 = 15 fps 
 00/03 ; 02: 
 00/07 ; 03:
 00/06 ; 04:
 00 03 ; 05:
 00 01 ; 06:
 00 04 ; 07:
 00 04 ; 08:
 00 04 ; 09:
 00 01 ; 0a:
 00 03 ; 0b:
 00 03 ; 0c:
 00 03 ; 0d:
 00 02 ; 0e:
 00 01 ; 0f: turnover animation plays at 60 fps
 00 02 ; 10:
 00 04 ; 11:
 00 04 ; 12:
 00 04 ; 13:

Mickey Physics

Music and Sfx