redhat man page for tk_imagechanged

Tk_ImageChanged(3)					       Tk Library Procedures						Tk_ImageChanged(3)

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NAME
       Tk_ImageChanged - notify widgets that image needs to be redrawn

SYNOPSIS
       #include <tk.h>

       Tk_ImageChanged(imageMaster, x, y, width, height, imageWidth, imageHeight)

ARGUMENTS
       Tk_ImageMaster imageMaster (in)		Token for image, which was passed to image's createProc when the image was created.

       int x (in)				X-coordinate  of upper-left corner of region that needs redisplay (measured from upper-left corner
						of image).

       int y (in)				Y-coordinate of upper-left corner of region that needs redisplay (measured from upper-left  corner
						of image).

       int width (in)				Width of region that needs to be redrawn, in pixels.

       int height (in)				Height of region that needs to be redrawn, in pixels.

       int imageWidth (in)			Current width of image, in pixels.

       int imageHeight (in)			Current height of image, in pixels.
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DESCRIPTION
       An  image manager calls Tk_ImageChanged for an image whenever anything happens that requires the image to be redrawn.  As a result of call-
       ing Tk_ImageChanged, any widgets using the image are notified so that they can redisplay themselves appropriately.  The	imageMaster  argu-
       ment  identifies the image, and x, y, width, and height specify a rectangular region within the image that needs to be redrawn.	imageWidth
       and imageHeight specify the image's (new) size.

       An image manager should call Tk_ImageChanged during its createProc 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, Tk_ImageChanged should be called again
       with x, y, width, and height values that cover all the pixels that changed.  If the size of the image should change,  then  Tk_ImageChanged
       must be called to indicate the new size, even if no pixels need to be redisplayed.

SEE ALSO
       Tk_CreateImageType

KEYWORDS
       images, redisplay, image size changes

Tk									4.0							Tk_ImageChanged(3)