Atari ST series - Page 343

The Line A Variable Table
+ 116 to +117 (+$074 to +$075)
COPYTRAN
line A Copy Raster mode:
Value Meaning
Zero Copy Raster Opaque
Nonzero Copy Raster Transparent
+ 118 to +121 ( + $076 to +$079)
SEEDABORT
Pointer to a routine called by the SeedFill function after each
horizontal line is filled. If this routine returns a value of zero
in register DO, Seed Fill continues filling the next scan line. If
this routine returns a nonzero value in DO, Seed Fill aborts.
At minimum, this vector should point to the routine:
seedabort: sub.l d0,d0 rts
If this vector is not set before calling Seed Fill, it will proba
bly point to an illegal address, and Seed Fill will bomb.
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