Image::Base::Tk::Photo -- draw with Tk::Photo
my $image = Image::Base::Tk::Photo->new (-for_widget => $mw,
-width => 100,
-height => 100);
$image->rectangle (0,0, 99,99, 'white');
$image->xy (20,20, 'black');
$image->line (50,50, 70,70, '#FF00FF');
$image->line (50,70, 70,50, '#0000AAAA9999');
Image::Base::Tk::Photo is a subclass of Image::Base,
Image::Base::Tk::Photo extends Image::Base to create or update image files using the Tk::Photo module from Perl-Tk.
See Tk::Photo for the supported file formats. Perl-Tk 804 includes
PNG, JPEG, XPM, XBM, GIF, BMP, PPM/PGM
TIFF separate Tk::TIFF module
A Tk::Photo requires a Tk::MainWindow and so an X display (etc), though there's no need to actually display the MainWindow. Drawing operations use the Photo pixel/rectangle put().
For reference, to draw arbitrary graphics in Perl-Tk the choice is between a Tk::Canvas with arcs etc, or a Tk::Photo of pixels which is set as the -image of a Tk::Label or similar. Is that right? No drawing area widget as such?
Colour names are anything recognised by Tk_GetColor(3tk), plus "None",
X server names usually /etc/X11/rgb.txt
The hex forms end up going to Xlib which means the shorter ones are padded with zeros, so "#FFF" is "#F000F000F000" which is a light grey rather than white. See X(7) "COLOR NAMES".
"None" means a transparent pixel, as per $tkphoto->transparencySet().
See "FUNCTIONS" in Image::Base for the behaviour common to all Image-Base classes.
$image = Image::Base::Tk::Photo->new (key=>value,...)
Create and return a new image object. It can be given an existing Tk::Photo,
$image = Image::Base::Tk::Photo->new (-tkphoto => $tkphoto);
Or it can create a new Tk::Photo. The -for_widget option gives a widget hierarchy where the new Tk::Photo will be used. A toplevel Tk::MainWindow is suitable.
$image = Image::Base::Tk::Photo->new (-for_widget => $widget);
-width and -height size can be given. Zero or omitted gives the usual auto-sizing of Tk::Photo.
$image = Image::Base::Tk::Photo->new (-for_widget => $widget,
-width => 200,
-height => 100);
Or a file can be read,
$image = Image::Base::Tk::Photo->new
(-for_widget => $widget,
-file => '/some/filename.xpm');
A Tk::Photo must be explicitly destroyed with $tkphoto->delete() the same as all Tk::Image types (see Tk::Image). Image::Base::Tk::Photo doesn't currently do that in its own destruction. Should it do so when it created the photo? But probably don't want to destroy when merely set in as a -tkphoto.
$new_image = $image->new (key=>value,...)
This is supposed to clone the image object, but it's not implemented yet. How to clone a Tk::Photo?
Read the current -file, or set -file to $filename and then read.
The file format is recognised automatically by Tk::Photo from the formats registered. Some formats are builtin, but for PNG, JPEG and TIFF the corresponding format modules Tk::PNG, Tk::JPEG or Tk::TIFF must be used first. For example,
Save to -file, or with a $filename argument set -file then save to that.
The saved file format is taken from -file_format (see "ATTRIBUTES" below) if that was set, either from a load() or explicit set().
For convenience, when saving PNG, JPEG and TIFF the necessary Tk::PNG, Tk::JPEG or Tk::TIFF module is loaded automatically. Any other non-builtin formats will require their modules loaded before attempting a save().
Setting these changes the size of the image.
The underlying Tk::Photo object.
The file format as a string like "png" or "jpeg", or undef if unknown or never set.
After load the -file_format is the format read. Setting -file_format can change the format for a subsequent save().
There's no attempt to check or validate the -file_format value since it's possible to add new formats to Tk::Photo at run time. Expect save() to croak if the format is unknown.
Tk::Photo, Image::Base, Image::Base::Tk::Canvas
Image-Base-Tk is Copyright 2010, 2011, 2012 Kevin Ryde
Image-Base-Tk is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3, or (at your option) any later version.
Image-Base-Tk is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with Image-Base-Tk. If not, see <http://www.gnu.org/licenses/>.
To install Image::Base::Tk::Photo, copy and paste the appropriate command in to your terminal.
perl -MCPAN -e shell
For more information on module installation, please visit the detailed CPAN module installation guide.