ID Number: Q75380
2.03 2.10 3.00 3.10
WINDOWS
Summary:
The DRAWPATTERNRECT escape is implemented by the PCL/HP driver for
Hewlett-Packard (HP) LaserJet printers and compatibles. The escape is
used to draw a patterned rectangle without using the graphics banding
bitmap. Using this escape can enhance the performance for many
applications, particularly when a majority of users have
LaserJet-compatible printers.
More Information:
The HP LaserJet Plus and all later LaserJets implement a command
called a rule. A rule is a rectangle filled with some pattern, such as
a black rule, a quasi-halftone gray scale, or a hatch pattern.
The output does not go through the graphics banding bitmap (it is
actually sent to the printer in the text band). The DRAWPATTERNRECT
escape can be used to print line and block graphics in the text band
without using graphics banding at all. Because many applications use
only horizontal and vertical lines or blocks, this is a significant
optimization.
An application should determine support for rules using the
QUERYESCSUPPORT escape. In particular, the application should not
check for the PCL/HP driver, since other page printer drivers may
implement the escape as well.
There are some limitations to the escape. First, rules drawn with
DRAWPATTERNRECT are not subject to clipping regions in the Device
Context (DC). Second, rules cannot be opaqued; no white pixel in the
graphics band will erase a pixel drawn by a rule (the same limitation
occurs for PCL text). Once a rule is drawn, it cannot be erased.
If these limitations are acceptable, if all graphics on the page are
likely to be horizontal and vertical lines, and if a significant
number of users are expected to have LaserJet-type printers (which is
the case for most Windows applications), the DRAWPATTERNRECT escape
should be used.
If for any reason DRAWPATTERNRECT cannot be used, then the application
should generally use the PatBlt function. If the device is a
plotter, the Rectangle function should be used. In the case of the
PatBlt function, if a black rectangle is to be printed, the BLACKNESS
raster operator (ROP) should be used to avoid the overhead of
selecting and later deselecting a black brush into the printer DC.
Additional reference words: 2.03 2.10 3.00 3.10 fast printing HPPCL HP-PCL