Difference between revisions of "AGI/Specifications/Booters"

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==Donald Duck's Playground==
 
==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 with the total capacity of 360KB (40 tracks, 2 heads, 9 sectors per track). The game uses AGI version 2.001.
 
[[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 with the total capacity of 360KB (40 tracks, 2 heads, 9 sectors per track). The game uses AGI version 2.001.
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===Directories===
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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:
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<pre>
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        Byte 0          Byte 1          Byte 2
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    7 6 5 4 3 2 1 0  7 6 5 4 3 2 1 0  7 6 5 4 3 2 1 0
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    . . . . S S S S  S S S S S S S O  O O O O O O O O
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</pre>
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where S is the sector number 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.

Revision as of 08:40, 26 May 2011

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 with the total capacity of 360KB (40 tracks, 2 heads, 9 sectors per track). 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 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.