bitmap(n) Tk (4.0) bitmap(n)
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NAME
bitmap - Images that display two colors
SYNOPSIS
image create bitmap ?name? ?options?
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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
Like all images, bitmaps are created using the image create
command. 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
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bitmap(n) Tk (4.0) bitmap(n)
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 COMMAND
When a bitmap image is created, Tk also creates a new
command whose name is the same as the image. This command
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
command. The following commands 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 command.
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 available options for imageName
(see Tk_ConfigureInfo for information on the format of
this list). If option is specified with no value, then
the command 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 command modifies the
given option(s) to have the given value(s); in this
case the command returns an empty string. Option may
have any of the values accepted by the image create
bitmap command.
KEYWORDS
bitmap, image
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