HP PCL/PJL reference (PCL 5 Color) - Technical Reference Manual

C-6 Using Palettes (Color LaserJet, 5, 5M, DeskJet) EN
Management by ID allows applications to tag data, have multiple
raster configurations, and have palettes for different color spaces—all
without reconfiguring the active palette. For example, one palette can
be created for PCL text, one for HP-GL/2 primitives, one for simple
raster, and one for 24-bit raster. The application can then switch
between palettes according to what is being sent to the printer.
Selecting a new active palette changes the PCL graphics state.
Besides color entries, a palette also contains the graphics state at the
time the bitmap representation of the palette colors was created. This
guarantees color reproduction integrity by insuring that the same
color specification triplet always produces the same bitmap
representation.
As described below, the Select Palette (
?&p#S), Palette Control
(
?&p#C), and Palette Control ID (?&p#I) commands implement the
three basic operations of management by ID.
• Selection of the active palette
• Deletion of palettes
• Copying of palettes
Select Palette Command
The Select Palette command selects a new active palette by
specifying an ID number. The previously active palette is unchanged.
?&p#S
This command activates the designated palette in the palette store.
The command is ignored if the specified ID matches the active
palette's ID, or if no palette with that ID exists. The designated ID is
saved as the palette select ID in the current modified print
environment.
# = Palette ID number
Default =0
Range = 0 to 32767 (command is ignored for out- of-range
values)