*
Texts:
* This is just a simple list of strings
* Each string can hold up to 255 characters, and it is terminated by a zero
* The length has been added at the start, to make it compatible with AMOS strings.
* Each string is referred to by its number, from an Interface program.
REPT Number_Of_Strings
dc.b 0
dc.b Length
dc.b "The string in plain Ascii"
ENDR
dc.b 0
* Holds one or more Interface command strings in standard Ascii format
* Offset list
DBL: dc.w Number_Of Programs
REPT Number_Of_Programs Each program has own offset value
dc.l Prog_N - DBL Offset to the Interface program
ENDR
* Repeat for each program
REPT Number_Of_Programs
Prog_N: One of these for each program
dc.w Prog_N_End - Prog_N Length of Interface string in bytes
dc.b "The text of the program, in Ascii"
dc.b "with a ZERO at the end..."
dc.b 0
Prog_N_End:
ENDR
COMPRESSED PICTURES (PIC.PAC)
The internal structure of these pictures is very complex, and this explanation is limited to the
header file. A full source listing of the compaction code is available from the extensions folder.
The packing process makes several attempts to provide the optimum compression ratio. It packs the picture into small blocks which are several lines high and exactly one byte wide. The height of the blocks is continually adjusted until the packer finds the most suitable value for the current data.
There are two possible cases. Either a compressed bitmap created with the PACK command, or a packed screen created with the SPACK instruction. The compressed bitmap is examined first.
* Magic number for a packed bitmap (Happy Birthday Francois Lionet!) Pkcode dc.l $06071963 * (Original X coordinate of the bitmap)/8 (in bytes) Pkdx dc.w x * Y coordinate of the original source data