1Tk_ImageChanged(3)           Tk Library Procedures          Tk_ImageChanged(3)
2
3
4
5______________________________________________________________________________
6

NAME

8       Tk_ImageChanged - notify widgets that image needs to be redrawn
9

SYNOPSIS

11       #include <tk.h>
12
13       Tk_ImageChanged(model, x, y, width, height, imageWidth, imageHeight)
14

ARGUMENTS

16       Tk_ImageMaster model (in)                Token  for  image,  which  was
17                                                passed to  image's  createProc
18                                                when the image was created.
19
20       int x (in)                               X-coordinate   of   upper-left
21                                                corner of  region  that  needs
22                                                redisplay  (measured  from up‐
23                                                per-left corner of image).
24
25       int y (in)                               Y-coordinate   of   upper-left
26                                                corner  of  region  that needs
27                                                redisplay (measured  from  up‐
28                                                per-left corner of image).
29
30       int width (in)                           Width  of region that needs to
31                                                be redrawn, in pixels.
32
33       int height (in)                          Height of region that needs to
34                                                be redrawn, in pixels.
35
36       int imageWidth (in)                      Current  width  of  image,  in
37                                                pixels.
38
39       int imageHeight (in)                     Current height  of  image,  in
40                                                pixels.
41______________________________________________________________________________
42

DESCRIPTION

44       An  image  manager calls Tk_ImageChanged for an image whenever anything
45       happens that requires the image to be redrawn.  As a result of  calling
46       Tk_ImageChanged,  any widgets using the image are notified so that they
47       can redisplay themselves appropriately.  The model argument  identifies
48       the  image,  and  x,  y, width, and height specify a rectangular region
49       within the image that needs to be redrawn.  imageWidth and  imageHeight
50       specify the image's (new) size.
51
52       Tk_ImageModel is synonym for Tk_ImageMaster                             │
53
54       An  image  manager should call Tk_ImageChanged during its createProc to
55       specify the image's initial size and to force redisplay  if  there  are
56       existing  instances  for  the image.  If any of the pixel values in the
57       image should change later on, Tk_ImageChanged should  be  called  again
58       with  x,  y,  width,  and  height values that cover all the pixels that
59       changed.  If the size of the image should change, then  Tk_ImageChanged
60       must  be  called to indicate the new size, even if no pixels need to be
61       redisplayed.
62

SEE ALSO

64       Tk_CreateImageType
65

KEYWORDS

67       images, redisplay, image size changes
68
69
70
71Tk                                    4.0                   Tk_ImageChanged(3)