Genicom GEK 00031B - Manual (Page 253)

GEK-00029B 5000 Series Programmer’s Manual 253
Printable Area
The printable area is the area on the paper where the printer can
physically print. The origin may be changed using the DECOPM
command. If DECOPM is reset, then the origin is at the corner of the
printable area. If DECOPM is set, then the origin is near the corner of
the physical page.
Unit Conversions and the Origin
Because the origin is at (1,1) and not (0,0), calculations need to take
this translation into account. The formula to convert from centipoints
to decipoints (and vice versa) is as follows:
target = ((source-1)*ratio)+1
where target is the coordinate in the new system, source is the
coordinate in the old system, and ratio is the size ratio between the
two measurement units.
For example, the coordinate system origin is at (1,1) in pixels,
decipoints, or centipoints. For a 300 dpi printer, the next diagonal
pixel is at (2,2) in pixel units, but at (25,25) in centipoints. Similarly,
a decipoint coordinate of (2,2) is at (11,11) in centipoints.
Positioning and Movement
Active Horizontal Position: This is the horizontal position where
printing will occur next. It is updated after each print operation.
Active Vertical Position: This is the vertical position where printing
will occur next. It is updated after each print operation.
Horizontal Advance Increment (HAI): This is added to the previous
Active Horizontal Position to determine the next Active Horizontal
position at the conclusion of a print operation. The classes of HAI are:
▪ Fixed
▪ Font-dependent
▪ Proportional
Vertical Advance Increment (VAI): This is added to the previous
Active Vertical Position to determine the next Active Vertical position
at the conclusion of a print operation. The two classes of VAI are:
▪ Fixed
▪ Font-dependent