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CloseRgn |
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| Header: | Quickdraw.h | Carbon status: | Supported | |
Organizes a collection of lines and shapes into a region definition.
void CloseRgn (
dstRgn
);
The handle to the region to close. This handle should be a region handle returned by the NewRgn function.
The CloseRgn function stops the collection of lines and framed shapes, organizes them into a region definition, and saves the result in the region whose handle you pass in the dstRgn parameter.
The CloseRgn function does not create the destination region; you must have already allocated space for it by using the OpenRgn function. The CloseRgn function calls the ShowPen function, balancing the call to the HidePen function made by OpenRgn.
When you no longer need the memory occupied by the region, use the DisposeRgn function.
If the points or rectangles supplied to this function are defined in a graphics port other than your current graphics port, you must convert them to the local coordinate system of your current graphics port. You can accomplish this by using the SetPort function to change to the graphics port containing the points or rectangles, using the LocalGlobal function to convert their locations to global coordinates, using SetPort to return to your starting graphics port, and then using the GlobalToLocal function to convert the locations of points or rectangles to the local coordinates of your current graphics port.
Regions are limited to 32 KB in size in basic QuickDraw and 64 KB in Color QuickDraw. When you structure drawing operations in an open region, the resulting region description may overflow this limit. Should this happen in Color QuickDraw, the QDError function returns the result code regionTooBigError. Since the resulting region is potentially corrupt, the CloseRgn function returns an empty region if it detects QDError has returned regionTooBigError.
The CloseRgn function may move or purge memory blocks in the application heap; do not call this function at interrupt time.
Supported in Carbon. Available in Carbon 1.0.2 and later when running Mac OS 8.1 or later.
© 2000 Apple Computer, Inc. (Last Updated 6/30/2000)