Bitmap
Section: User Contributed Perl Documentation (3)
Updated: 2021-01-27
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NAME
Tk::Bitmap - Images that display two colors
SYNOPSIS
$image
=
$widget
->
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 background color,
a foreground color, and two bitmaps, called the
source
and the
mask.
Each of the bitmaps specifies 0/1 values for a rectangular
array of pixels, and the two bitmaps must have the same
dimensions.
For pixels where the mask is zero, the image displays nothing,
producing 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
Bitmaps are created using
$widget
->
Bitmap.
Bitmaps support the following
options:
- -background => color
-
Specifies a background color for the image in any of the standard
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 standard
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 specified,
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 the bitmap program).
IMAGE METHODS
When a bitmap image is created, Tk also creates a new object.
This object supports the
configure and
cget methods
described in Tk::options which can be used to enquire and
modify the options described above.
SEE ALSO
Tk::Image
Tk::Pixmap
Tk::Photo
KEYWORDS
bitmap, image