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#define BANDINFO 24 
short Control(lpDevice, BANDINFO, lpInData, lpOutData)
LPPDEVICE lpDevice;
LPBANDINFOSTRUCT lpInData;
LPBANDINFOSTRUCT lpOutData;
 
The BANDINFO escape copies information about a device with banding
capabilities to a structure pointed at by the lpInData parameter.
 
Banding is a property of an output device that allows a page of output to be
stored in a metafile and divided into bands, each of which is sent to the
device to create a complete page. Use banding with devices that cannot
scroll backwards.
 
The information copied to the structure pointed at by lpInData includes a
flag indicating whether or not there are graphics in the next band, a flag
indicating whether or not there is text on the page, and a rectangle
structure that contains a bounding rectangle for all graphics on the page.
 
Parameter  Description
────────────────────────────────────────────────────────────────────────────
 
 
lpDevice   Points to a PDEVICE structure specifying the destination device.
 
lpInData   Points to a BANDINFOSTRUCT structure containing information about
           the graphics band.
 
lpOutData  Points to a BANDINFOSTRUCT structure containing information about
           the graphics band.
 
Return Value
 
The return value is 1 if the escape is successful. Otherwise, it is 0.
 
Comments
 
This escape should only be implemented for devices that use banding. It
should be called immediately after each call to the NEXTBAND escape. If the
lpOutData parameter is not NULL and graphics will be printed in the current
band, the driver will set the fGraphics member in the output structure. If
text will be printed, the fText member will be nonzero. The rcGraphics
member is not used for output.
 
Therefore, on the first band, the driver would set the rectangle returned by
NEXTBAND to the whole page. If it receives a BANDINFO escape, it will set
the fText member and clear fGraphics.
 
On subsequent bands, it will band the page in small rectangles and handle
only graphics calls. Additionally, if the application calls BANDINFO, clears
the fText member and sets fGraphics.
 
The application can also optimize the banding process somewhat by describing
the page with the structure passed by lpInData. The application sets the
fGraphics member, if there are any graphics on the page, and the fText
member if there is any text. If there are no graphics, the driver may be
able to skip the graphics bands. The application should also set rcGraphics
to the rectangle bounding all nontext graphics on the page. The driver has
the option of banding only the specified graphics rectangle rather than the
whole page.
 
Vector fonts complicate the process somewhat. Since vector devices using
banding generally cannot print vector fonts, these fonts are simulated using
polylines or scan lines. Therefore, they appear to the driver to be graphics
in the text band. Since vector fonts can appear anywhere on the page and
require graphics banding support, the driver must band graphics on the whole
page even if the BANDINFOSTRUCT passed by the application specifies
otherwise.
 
If the application never calls BANDINFO, the driver can decide whether or
not to band graphics by maintaining a flag that is set if any graphics calls
are seen during the text band.
 
See Also
 
NEXTBAND, BANDINFOSTRUCT
 
 
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