PATHMac OS 8 and 9 Developer Documentation > Human Interface Toolbox > Window Manager >

Programming With the Mac OS 8.5 Window Manager

ValidWindowRgn

Removes a region from a window's update region.

pascal OSStatus ValidWindowRgn (
                     WindowPtr window,
                     RgnHandle region);
window
A value of type WindowPtr . Pass a pointer to the window containing the region that you wish to remove from being updated.
region
A value of type RgnHandle . Before calling ValidWindowRgn , set this region to specify, in local coordinates, the area to be removed from the window's update region.
function result
A result code. See Result Codes.
DISCUSSION

The ValidWindowRgn function informs the Window Manager that an area of a window no longer needs to be redrawn. The ValidWindowRgn function is similar to the ValidRgn function, but ValidWindowRgn allows the window that it operates upon to be explicitly specified, instead of operating on the current graphics port, so ValidWindowRgn does not require the graphics port to be set before its use. See Maintaining the Update Region for further discussion.

VERSION NOTES

Available with Mac OS 8.5 and later.

SEE ALSO

The function InvalWindowRgn .

The function ValidWindowRect .

© 1999 Apple Computer, Inc. – (Last Updated 18 March 99)