Legacy Document

Inside Macintosh: Imaging With QuickDraw /

Chapter 4 - Color QuickDraw / Color QuickDraw Reference

Color QuickDraw Routines / Reporting Data Structure Changes to QuickDraw

PixPatChanged

If you modify the content of a PixPat record (described on page 4-49), including its PixMap record or the image in its patData field, use the PixPatChanged procedure.

PROCEDURE PixPatChanged (ppat: PixPatHandle);

ppat

A handle to the changed pixel pattern.

DESCRIPTION

The PixPatChanged procedure sets the patXValid field of the PixPat record specified in the ppat parameter to -1 and notifies QuickDraw of the change.

If your application changes the pmTable field of a pixel pattern's PixMap record, it should call PixPatChanged. However, if your application changes the content of the color table referenced by the PixMap record's pmTable field, it should call PixPatChanged and the CTabChanged procedure as well. (The CTabChanged procedure is described in the preceding section.)

SPECIAL CONSIDERATIONS

The PixPatChanged procedure may move or purge memory in the application heap. Your application should not call the PixPatChanged procedure at interrupt time.

Your application should never need to directly modify a PixPat record and use the PixPatChanged procedure; instead, your application should use the QuickDraw routines described in this book for manipulating the values in a PixPat record.

ASSEMBLY-LANGUAGE INFORMATION

The trap macro and routine selector for the PixPatChanged procedure are

Trap macro	Selector
_QDExtensions	$00040008