6.1.4 Graphics Block Data

The fBlockOut dialog box contains controls which specify how the Universal
Printer Driver formats each block of raster-graphic data to be sent to the
printer. A block is defined as having a height of n scan lines where n is
equal to the sNPins control. (For more information about the sNPins
control, see Section 6.1.6, Number of Pins.) The fBlockOut dialog box
controls the following bits:

o   Whether the Universal Printer Driver should strip leading, embedded,
    and trailing blanks from the bitmap data prior to sending the data to
    the printer.

o   Whether the Universal Printer Driver needs to reset the currently
    selected device font after printing bitmap data.

o   Whether the printer requires undirectional printing with the specified
    resolution.

o   Whether the printer cannot fire adjacent pins in the print head.

o   Whether the Universal Printer Driver needs to reset the raster
    data-compression mode after printing bitmap data.

o   Whether the minidriver provides a callback function which alters bitmap
    data prior to printing.

The following illustration shows the fBlockOut dialog box:

bitmap:  fblckout

The following list briefly describes the controls in the fBlockOut dialog
box.

Control                 Description
---------------------------------------------------------------------------

RES_BO_LEADING_BLNKS    Specifies that the Universal Printer Driver should
                        strip any leading, non-printing graphic data from
                        the beginning of each block of raster data sent to
                        the printer.

RES_BO_TRAILING_BLNKS   Specifies that the Universal Printer Driver should
                        strip any trailing, nonprinting graphic data from
                        the end of each block of raster data sent to the
                        printer.

RES_BO_ENCLOSED_BLNKS   Specifies that the Universal Printer Driver should
                        strip any enclosed, nonprinting graphic data from
                        anywhere within each block of raster data sent to
                        the printer, if the number of bytes of nonprinting
                        raster data exceeds that value listed in the
                        sMinBlankSkip control in the RESOLUTION dialog box.

RES_BO_RESET_FONT       Specifies that the Universal Printer Driver should
                        reset the currently selected device font after
                        printing a block of raster-bitmap data.

RES_BO_UNIDIR           Specifies that the Universal Printer Driver should
                        enable unidirectional printing, from the data in
                        the CURSORMOVE dialog box, when using this
                        resolution. Some printers require this for correct
                        horizontal alignment of output.

RES_BO_NO_ADJACENT      Specifies that the Universal Printer Driver should
                        be aware that vertically adjacent pins on the print
                        head may not be fired simultaneously.

RES_BO_RESET_CMP        Specifies that the Universal Printer Driver should
                        reset the raster data-compression mode after
                        entering graphics mode.

RES_BO_CB_FILTER_GRX    Specifies that the Universal Printer Driver should
                        use code provided by the driver to alter raster
                        graphic data.

NOTEÿThe term strip raster graphics data means that Universal Printer
Driver will substitute available cursor-movement commands in place of
nonprinting raster-graphic data. This usually results in a performance gain
because cursor-movement commands typically require less data when sent to
the printer. Most printers will benefit from using the
RES_BO_TRAILING_BLNKS bit. However, due to differences in the resolutions
of cursor-movement commands and graphics resolutions, care must be
exercised when using the RES_BO_LEADING_BLNKS and RES_BO_ENCLOSED_BLNKS
bits to ensure that horizontal misalignment of graphic output does not
occur.


Diconix 150 Plus

For the Diconix 150 Plus printer, the RES_BO_TRAILING_BLNKS box is checked
in order to delete trailing blanks from a bitmap. However, the
RES_BO_LEADING_BLNKS and RES_BO_ENCLOSED_BLNKS boxes are not checked
because the available methods of moving the cursor do provide a high enough
degree of accuracy.


HP LaserJet IIP

For the HP LaserJet IIP printer, the RES_BO_ENCLOSED_BLNKS box is checked
in order to delete blanks enclosed in the bitmap. The RES_BO_TRAILING_BLNKS
box is also checked in order to delete trailing blanks from a bitmap.
However, the RES_BO_LEADING_BLNKS box is not checked. (The performance of
HP PCL minidrivers is significantly reduced when this box is checked and
the Universal Printer Driver removes leading blanks from a bitmap.)