hdc (HDC) - input

Device context handle.

hrgn (HRGN) - input

Region handle.

parcRgn (PRECTL) - input

Pointer to region definition.

The region is defined as an array of rectangles. Each rectangle in the array is defined by a RECTL structure:

xLeft

Minimum X-coordinate of rectangle
yBottom
Minimum Y-coordinate
xRight
Maximum X-coordinate of rectangle
yTop
Maximum Y-coordinate
The region is defined by the OR of all the rectangles. For each rectangle, xRight must be equal to or greater than xLeft. yTop must be equal to or greater than yBottom. The bottom and left boundaries of each rectangle are part of the interior of the region, the top and right boundaries are not. If COM_TRANSFORM is not set, the function expects rectangles to be in device coordinates.

cRect (LONG) - input

Count of rectangles in the region definition.

pInstance (PVOID) - input

Pointer to instance data.

lFunction (ULONG) - input

High-order WORD=flags; low-order WORD=NGreSetRectRegion.

fSuccess (BOOL) - returns

Return codes.

This function returns BOOLEAN (fSuccess).

TRUE

Successful
FALSE
Error.
Possible Errors Detected: When an error is detected, the handling routine must call WinSetErrorInfo to post the condition. Error codes for conditions that the handling routine is expected to check include:

PMERR_HRGN_BUSY PMERR_INSUFFICIENT_MEMORY
PMERR_INV_COORDINATE
PMERR_INV_HRGN
PMERR_INV_LENGTH_OR_COUNT
PMERR_INV_RECT
PMERR_REGION_IS_CLIP_REGION

Refer to the "Error Explanations" section in the Presentation Manager Programming Reference for further explanation.