<HTML><HEAD><TITLE>Tk Library Procedures - Tk_ImageChanged manual page</TITLE></HEAD><BODY> <H3><A NAME="M2">NAME</A></H3> Tk_ImageChanged - notify widgets that image needs to be redrawn <H3><A NAME="M3">SYNOPSIS</A></H3> <B>#include <tk.h></B><BR> <B>Tk_ImageChanged</B>(<I>imageMaster, x, y, width, height, imageWidth, imageHeight</I>)<BR> <H3><A NAME="M4">ARGUMENTS</A></H3> <DL> <P><DT>Tk_ImageMaster <B>imageMaster</B> (in)<DD> Token for image, which was passed to image's <I>createProc</I> when the image was created. <P><DT>int <B>x</B> (in)<DD> X-coordinate of upper-left corner of region that needs redisplay (measured from upper-left corner of image). <P><DT>int <B>y</B> (in)<DD> Y-coordinate of upper-left corner of region that needs redisplay (measured from upper-left corner of image). <P><DT>int <B>width</B> (in)<DD> Width of region that needs to be redrawn, in pixels. <P><DT>int <B>height</B> (in)<DD> Height of region that needs to be redrawn, in pixels. <P><DT>int <B>imageWidth</B> (in)<DD> Current width of image, in pixels. <P><DT>int <B>imageHeight</B> (in)<DD> Current height of image, in pixels. <P></DL> <H3><A NAME="M5">DESCRIPTION</A></H3> An image manager calls <B>Tk_ImageChanged</B> for an image whenever anything happens that requires the image to be redrawn. As a result of calling <B>Tk_ImageChanged</B>, any widgets using the image are notified so that they can redisplay themselves appropriately. The <I>imageMaster</I> argument identifies the image, and <I>x</I>, <I>y</I>, <I>width</I>, and <I>height</I> specify a rectangular region within the image that needs to be redrawn. <I>imageWidth</I> and <I>imageHeight</I> specify the image's (new) size. <P> An image manager should call <B>Tk_ImageChanged</B> during its <I>createProc</I> to specify the image's initial size and to force redisplay if there are existing instances for the image. If any of the pixel values in the image should change later on, <B>Tk_ImageChanged</B> should be called again with <I>x</I>, <I>y</I>, <I>width</I>, and <I>height</I> values that cover all the pixels that changed. If the size of the image should change, then <B>Tk_ImageChanged</B> must be called to indicate the new size, even if no pixels need to be redisplayed. <H3><A NAME="M6">SEE ALSO</A></H3> <B><A HREF="../TkLib/CrtImgType.htm">Tk_CreateImageType</A></B> <H3><A NAME="M7">KEYWORDS</A></H3> <A href="../Keywords/I.htm#images">images</A>, <A href="../Keywords/R.htm#redisplay">redisplay</A>, <A href="../Keywords/I.htm#image size changes">image size changes</A> <HR><PRE> <A HREF="../copyright.htm">Copyright</A> © 1994 The Regents of the University of California. <A HREF="../copyright.htm">Copyright</A> © 1994-1996 Sun Microsystems, Inc. <A HREF="../copyright.htm">Copyright</A> © 1995-1997 Roger E. Critchlow Jr.</PRE> </BODY></HTML>