Information About Clipping, GetDeviceCaps() and GDI
ID: Q22538
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The information in this article applies to:
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Microsoft Windows Software Development Kit (SDK) versions 3.0, 3.1
SUMMARY
When the GetDeviceCaps(hDC,CLIPCAPS) function is used on an Epson
FX-80 printer, it returns zero (0), which means that the printer does
not support clipping. The explanation below describes how the
GetDeviceCaps() function, the Windows Graphics Device Interface (GDI),
and clipping interact with each other.
The GetDeviceCaps() function reports what subset of the GDI services
the device directly supports. The complete list of GDI services is
available in the documentation. The GDI will simulate functions that
the device does not directly support using those functions that are
available on the device.
The Epson FX-80 printer does not support clipping to any particular
portion of the page, even in graphics mode, which is precisely what
the GetDeviceCaps() function indicates.
GDI provides at least a minimum level of services for all devices. In
particular, if a clipshape is set while a document is being printed,
the programmer can be assured that GDI will honor that clipshape. GDI
works with the information returned in the GetDeviceCaps() function to
determine what services GDI must provide on behalf of the device. In
this case, the printer does not perform clipping; clipping is provided
by GDI. The GetDeviceCaps() function can indicate how much additional
work GDI must perform to accomplish a particular function. The
programmer may want to modify a request to speed processing.
Also note that DC stands for device context. The most interesting DC
is for the display [and, in fact, it is the device context for the
display that is returned by GetDC(), and in the PAINTSTRUCT structure
returned by BeginPaint()]. Printer DCs are NEVER contexts for the
display; they are device contexts.
Additional query words:
3.00 no32bit 3.10
Keywords : kb16bitonly
Version : WINDOWS:3.0,3.1
Platform : WINDOWS
Issue type :