make-image(n)                    STk procedure                   make-image(n)



NAME
       create-image, find-image, change-image, free-image  - an easier way to
       manipulate Tk images


PACKAGE
       Tk


SYNOPSIS
       (make-image key create image ?options?)
       (find-image key)
       (change-image key  create image options)
       (free-image key)


DESCRIPTION
       make-image is a STk procedure which simplifies Tk images creation by
       providing a homogeneous way to create an image, independently of its
       coding format.  The first argument of make-image is a string which
       identifies the image; if an image with this key has been already loaded
       in memory, it will not be loaded again and make-image will return it.
       If no option is given, the identifying image key is taken as a file
       name (the file is searched using the variable *image-path*, which must
       contain a set of prefix pathnames to prepend to the given filename).
       If options are passed to the make-image  procedure they must follow the
       convention of the options passed in image create just after the image
       format. If the image cannot be created, this procedure returns #f.

       Hereafter is a simple usage of this procedure:

       (require "image") (require "pixmap")

       (define img1 (make-image "a pixmap" :file "exit.xpm")) (define img2
       (make-image "a bitmap" :file "default.xbm")) (define img3 (make-image
       "a pixmap")) (define img4 (make-image "x.xpm")) In this case, img3 is
       identical to img1 since they use the same key.  Img4 is the image
       associated to the file "x.xpm" found according to the  *image-path*
       varaiable.


       find-image returns the image associated to the given key or #f if this
       image has not been loaded yet.


       change-image changes the content of an image previously created with
       make-image. Options are the identical to make-image options.

       Example: (button '.b1 :image img1) (button '.b2 :image img2) (button
       '.b3 :image img1) ; .b3 content is identical to .b1 (pack .b1 .b2 .b3)
       (change-image "a pixmap" :file "default.xbm") After the execution of
       change-image, both .b1 and .b3 graphical contents are changed.


       delete-image removes the image with the given key of the cache.  The
       memory used by this image is returned to the system. See the discussion
       about how this image is displayed in image delete.


SEE ALSO
       bitmap, image, jpeg, photo, pixmap



STk                                   3.2                        make-image(n)
