Image::Button

Section: User Contributed Perl Documentation (3)
Updated: 2003-03-04
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NAME

Image::Button - Base class for building PNG buttons using GD.  

SYNOPSIS

  use Image::Button::Rect;

  my $b1 = new Image::Button::Rect(text     => 'text b1',
                                   font     => 'newsgotn.ttf',
                                   fontsize => 20,
                                   file     => 'b1.png');

  # $b2 is like $b1, but with different text and going to another file
  my $b2 = $b1->copy(text => 'text b2',
                     file => 'b2.png');

  $b1->print;
  $b2->print;

 

DESCRIPTION

Image::Button builds simple PNG buttons of the type you would use in an on-line application. It provides facilities to build several of them, possibly related (same width and/or height). Modules to create different types of buttons can be easily integrated. The buttons it can create so far would not cause a graphic designer to jump from his chair, drooling with excitement. But he wouldn't fall from his chair in disgust either (I hope).  

Fonts

Image::Button uses GD with TrueType support, which requires freetype (http://www.freetype.org). It also requires true type fonts. It's remarkably difficult to find free fonts out there that can be used to make decent buttons (clean, non-pretentious, ideally sans-serif). Let me know if you find any.

The TrueType fonts should be located either in the current directory or in the directory pointed at by the environment variable TTFONTS.  

Adding new button types

Image::Button is a base class intended to be derived by classes implementing different types of buttons. Available so far are:
Image::Button::Plain,
plain rectangular buttons with an optional border,
Image::Button::Rect,
rectangular three dimensional buttons.

If you want to implement a new type of button (say, oval) you can take advantage of the existing infrastructure by deriving from Image::Button, and overriding the print, getSize and textSize functions, as Image::Button::Plain does.  

FUNCTIONS

There is only OO interface to the packages, and all function calls require named parameters.  

Constructor

The way to construct the button will depend on the button type being constructed, but it will generally be of the form:

  my $b = new Image::Button::Rect(text     => 'text',
                                  font     => 'newsgotn.ttf',
                                  fontsize => 20,
                                  fgcolor  => [ 85, 85, 136 ], # text
                                  btcolor  => [ 238, 238, 204 ],
                                  bgcolor  => [ 255, 255, 255 ],
                                  file     => 'file.png');

See the man page of the button you are trying to construct for a description of the arguments.  

Print the button

    $b->print(file    => 'button.png',
              prefix  => '',
              postfix => '');

Prints the button to a file. If the file argument is not set it will print to the one specified in the button constructor. The prefix and postfix arguments are prepended and appended to the file name, respectively. They are useful when printing sets of buttons, where you might want to print them several times, with small modifications, to different file names (for example, changing the color).  

Copy the button

    $b2 = $b->copy(text     => 'new text',
                   file     => 'button2.png',
                   fontsize => 21);

Copy constructor. If no arguments are specified returns an exact copy of the original button. If called with any of the arguments of the original button constructor it will override the original button's values. Use it to build sets of related buttons; for example, same font and colors, but different texts and output files.  

Change the button

  $b->override(self => { btcolor  => [10, 10, 10],
                         fontsize => 12 });

Accepts a dictionary reference self with new parameters. Any parameter that the button's constructor understands can be reset here.  

SEE ALSO

Image::Button::Plain for specifics on plain rectangular buttons.

Image::Button::Rect for specifics on 3D rectangular buttons.

Image::Button::Set for building sets of related buttons.  

TODO

Add tests. Oval buttons. Triangular buttons (arrow type).  

AUTHOR

Juan M. García-Reyero <joanmg@twostones.org>  

COPYRIGHT

Copyright (C) 2003 Juan M. García-Reyero. All Rights Reserved.

This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself.


 

Index

NAME
SYNOPSIS
DESCRIPTION
Fonts
Adding new button types
FUNCTIONS
Constructor
Print the button
Copy the button
Change the button
SEE ALSO
TODO
AUTHOR
COPYRIGHT

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