- Extension: RBT
- Company: Sierra Entertainment
Robot files are animation files used in various Sierra computer games. It is a container format that encapsulates video and possibly audio.
All multi-byte numbers are little-endian.
The general organization of a Robot file is as follows:
<header> <unknown block> <palette> <video frame size table> <frame size table> <padding> <frame 1> <frame 2> ... <frame n>
A Robot file begins with the following variable-length header.
bytes 0-5 signature and probably a version (16 00 53 4f 4c 00; bytes 2-4 are 'SOL') bytes 6-7 version bytes 8-9 audio chunk size bytes 10-11 silence chunk size bytes 12-13 unknown bytes 14-15 frame count bytes 16-17 palette data size bytes 18-19 unknown chunk data size bytes 20-24 unknown byte 25 has sound bytes 26-59 unknown bytes 60.. unknown data chunk, size defined by bytes 18-19
After the header is a palette chunk. The size of the palette chunk is defined it bytes 16-17 of the header. The first 37 or 38 bytes have the following format:
bytes 0-24 unknown byte 25 first palette index to replace bytes 29-30 palette count byte 32 palette format (0 = variable, 1 = constant) bytes 33-[36,37] unknown byte [37,38].. palette components
The palette is 256 total entries, though the palette encoded in this chunk is only likely to encode a partial palette since the other colors are reserved for other parts of the game's user interface.
Replace (palette count) entries in the palette starting with the index specified by byte 25. The palette components are ordered red - green - blue - red - green - blue - etc. The palette components begin at index 37 for constant palettes and 38 for variable palettes.
Each palette component is 8 bits.
Versions and Games
These are the known Robot format versions known to be associated with particular games and SCI engine revisions:
- Version 4: Police Quest: SWAT (demo)
- Version 5: SCI 2.1 and SCI 3
- Version 6: SCI 3