


bitmap(n)              Tk Built-In Commands             bitmap(n)


NAME
       bitmap - Images that display two colors

SYNOPSIS
       (image 'create 'bitmap ?name? ?options?)


DESCRIPTION
       A  bitmap  is an image whose pixels can display either of two colors or
       be transparent.  A bitmap image is defined by  four  things:   a  back-
       ground  color,  a  foreground color, and two bitmaps, called the source
       and the mask.  Each of the bitmaps specifies 0/1 values for a rectangu-
       lar array of pixels, and the two bitmaps must have the same dimensions.
       For pixels where the mask is zero, the image displays nothing,  produc-
       ing  a  transparent  effect.   For other pixels, the image displays the
       foreground color if the source data is one and the background color  if
       the source data is zero.


CREATING BITMAPS
       Like  all images, bitmaps are created using the image create procedure.
       Bitmaps support the following options:

       :background color
              Specifies a background color for the image in any of  the  stan-
              dard  ways  accepted  by  Tk.  If this option is set to an empty
              string then the background pixels  will  be  transparent.   This
              effect  is  achieved  by  using  the  source  bitmap as the mask
              bitmap, ignoring any :maskdata or :maskfile options.

       :data string
              Specifies the contents of the source bitmap as  a  string.   The
              string  must  adhere to X11 bitmap format (e.g., as generated by
              the bitmap program).  If both the :data and  :file  options  are
              specified, the :data option takes precedence.

       :file name
              name  gives  the name of a file whose contents define the source
              bitmap.  The file must adhere to X11  bitmap  format  (e.g.,  as
              generated by the bitmap program).

       :foreground color
              Specifies  a  foreground color for the image in any of the stan-
              dard ways accepted by Tk.

       :maskdata string
              Specifies the contents of the mask as a string.  The string must
              adhere  to  X11  bitmap format (e.g., as generated by the bitmap
              program).  If both the :maskdata and :maskfile options are spec-
              ified, the :maskdata option takes precedence.

       :maskfile name
              name  gives  the  name of a file whose contents define the mask.
              The file must adhere to X11 bitmap format (e.g., as generated by



STk                            3.1                              1





bitmap(n)              Tk Built-In Commands             bitmap(n)


              the bitmap program).


IMAGE PROCEDURE
       When  a  bitmap image is created, Tk also creates a new procedure whose
       name is the same as the image.  This procedure may be  used  to  invoke
       various  operations  on  the image.  It has the following general form:
       (imageName option ?arg arg ...?)  Option and  the  args  determine  the
       exact behavior of the procedure.  The following procedures are possible
       for bitmap images:

       (imageName cget option)
              Returns the current value of the configuration option  given  by
              option.  Option may have any of the values accepted by the image
              create bitmap procedure.

       (imageName configure ?option? ?value option value ...?)
              Query or modify the configuration options for the image.  If  no
              option is specified, returns a list describing all of the avail-
              able options for imageName (see Tk_ConfigureInfo for information
              on  the  format  of  this list).  If option is specified with no
              value, then the procedure returns  a  list  describing  the  one
              named  option  (this list will be identical to the corresponding
              sublist of the value returned if no option  is  specified).   If
              one or more option-value pairs are specified, then the procedure
              modifies the given option(s) to have  the  given  value(s);   in
              this  case  the  procedure  returns an empty string.  Option may
              have any of the values accepted by the image create bitmap  pro-
              cedure.


SEE ALSO
       make-image, image, jpeg, photo, pixmap
























STk                            3.1                              2


