Overview
Group
Quick Info

Windows NT
Yes
Win95
Yes
Win32s
No
Import Library
gdi32.lib
Header File
wingdi.h
Unicode
No
Platform Notes
Windows 95: 16-bit coordinates only

ExtSelectClipRgn

The ExtSelectClipRgn function combines the specified region with the current clipping region by using the specified mode.

int ExtSelectClipRgn(

HDC hdc,
// handle to device context
HRGN hrgn,
// handle to region
int fnMode
// region-selection mode
);

Parameters

hdc

Identifies the device context.

hrgn

Identifies the region to be selected. This handle can only be NULL when the RGN_COPY mode is specified.

fnMode

Specifies the operation to be performed. It must be one of the following values:

Value
Meaning
RGN_AND
The new clipping region combines the overlapping areas of the current clipping region and the region identified by hrgn.
RGN_COPY
The new clipping region is a copy of the region identified by hrgn. This is identical to SelectClipRgn. If the region identified by hrgn is NULL, the new clipping region is the default clipping region (the default clipping region is a null region).
RGN_DIFF
The new clipping region combines the areas of the current clipping region with those areas excluded from the region identified by hrgn.
RGN_OR
The new clipping region combines the current clipping region and the region identified by hrgn.
RGN_XOR
The new clipping region combines the current clipping region and the region identified by hrgn but excludes any overlapping areas.

Return Values

If the function succeeds, the return value specifies the new clipping region's complexity and can be any one of the following values:

Value
Meaning
NULLREGION
Region is empty.
SIMPLEREGION
Region is a single rectangle.
COMPLEXREGION
Region is more than one rectangle.
ERROR
An error occurred.

Remarks

If an error occurs when this function is called, the previous clipping region for the specified device context is not affected.

The ExtSelectClipRgn function assumes that the coordinates for the specified region are specified in device units.

Only a copy of the region identified by the hrgn parameter is used. The region itself can be reused after this call or it can be deleted.

See Also

SelectClipRgn

Software for developers
Delphi Components
.Net Components
Software for Android Developers
More information resources
MegaDetailed.Net
Unix Manual Pages
Delphi Examples
Databases for Amazon shops developers
Amazon Categories Database
Browse Nodes Database