HP PCL/PJL reference (PCL 5 Printer Language) - Technical Reference Manual Part II

22-42 The Line and Fill Attributes Group EN
TR, Transparency Mode
This command defines how the white areas of the source graphics
image affect the destination graphics image.
TR [n][;]
or
TR [;]
z No Parameters— Defaults to transparency mode = on (TR1;).
z n— Specifies whether transparency mode is on or off:
z 0— Transparency mode = off.
z 1— Transparency mode = on (default).
When transparency mode is on (default), the portion of a source
image which is defined by white pixels does not affect the destination;
whatever was already written to the page “shows through” the white
areas in the new image.
Figure 22-22Transparency Mode = ON
Parameter Format Functional Range Default
n clamped integer 0 or 1 1 (on)