SetBoundsRect

Overview

Group

Quick Info

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

The SetBoundsRect function controls the accumulation of bounding rectangle information for the specified device context. Windows can maintain a bounding rectangle for all drawing operations. An application can examine and set this rectangle. The drawing boundaries are useful for invalidating bitmap caches.

UINT SetBoundsRect(

HDC hdc,	// handle of device context
CONST RECT *lprcBounds,	// address of rectangle coordinates
UINT flags	// controls rectangle combination
);

Parameters
hdc

Identifies the device context for which to accumulate bounding rectangles.

lprcBounds

Points to a RECT structure used to set the bounding rectangle. Rectangle dimensions are in logical coordinates. This parameter can be NULL.

flags

Specifies how the new rectangle will be combined with the accumulated rectangle. This parameter can be a combination of the following values:

Value	Description
DCB_ACCUMULATE	Adds the rectangle specified by the lprcBounds parameter to the bounding rectangle (using a rectangle union operation). Using both DCB_RESET and DCB_ACCUMULATE sets the bounding rectangle to the rectangle specified by the lprcBounds parameter.
DCB_DISABLE	Turns off boundary accumulation.
DCB_ENABLE	Turns on boundary accumulation, which is disabled by default.
DCB_RESET	Clears the bounding rectangle.

Return Values
If the function succeeds, the return value specifies the previous state of the bounding rectangle. This state can be a combination of the following values:

Value	Meaning
DCB_DISABLE	Boundary accumulation is off.
DCB_ENABLE	Boundary accumulation is on. DCB_ENABLE and DCB_DISABLE are mutually exclusive.
DCB_RESET	Bounding rectangle is empty.
DCB_SET	Bounding rectangle is not empty. DCB_SET and DCB_RESET are mutually exclusive.

Remarks
The DCB_SET value is a combination of the bit values DCB_ACCUMULATE and DCB_RESET. Applications that check the DCB_RESET bit to determine whether the bounding rectangle is empty must also check the DCB_ACCUMULATE bit. The bounding rectangle is empty only if the DCB_RESET bit is 1 and the DCB_ACCUMULATE bit is 0.