AGI/Specifications/Booters

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Booter versions of AGI games

Donald Duck's Playground

Donald Duck's Playground is an adventure game that was originally released for the IBM PC as a booter on a 5.25-inch double-density floppy disk (40 tracks, 2 heads, 9 sectors per track, total capacity 360KB). The game uses AGI version 2.001.

Directories

On the disk there exists directories that are equivalent to the logdir, picdir, viewdir and snddir in the DOS-based AGI games. Each directory entry is a (sector,offset) pair that indicates where on the disk is the beginning of the resource. The format of each entry is:

        Byte 0           Byte 1           Byte 2
    7 6 5 4 3 2 1 0  7 6 5 4 3 2 1 0  7 6 5 4 3 2 1 0
    . . . . S S S S  S S S S S S S O  O O O O O O O O

where S is the sector number and O the offset in that sector. Actually the sector number is not the absolute sector but an offset that is added to a base sector for all game resources. This base sector is the beginning of the DOS VOL-equivalent.

Volume (VOL) format

The volume format is exactly the same as in DOS-based AGI v2 games.

Further, most of the game resource formats are also identical to v2 games. An exception is the SOUND resource format that carries over from earlier AGI versions.