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NAME

Image::BoxModel::Lowlevel - Lowlevel functions for Image::BoxModel

SYNOPSIS

  For an example and general information see Image::BoxModel.pm

DESCRIPTION

Image::BoxModel::Lowlevel implements some basic functionality.

It does so by using the methods from Image::BoxModel::Backend::[LIBRARY]

There are more backends planned and more functionality for each backend. (backends, patches, wishes are very welcome - in this order ;-)

Image::BoxModel::Lowlevel can be used directly, which is considered painful sometimes. You need to specify the size of a box before you can put text on it, for example, while 'Annotate' (inherited from ::Text) easily inserts a box and puts text on it. On the other hand, ::Lowlevel gives you full control.

Methods:

GetBoxSize

 ($width, $height) = $image -> GetBoxSize (box => "name_of_your_box");

Box

If you don't specify 'resize => $name_of_box_to_be_resized', the standard-box 'free' is chosen.

 $image -> Box (
        position =>[left|right|top|bottom], 
        width=> $x, 
        height => $y, 
        name => $name_of_new_box
 );

FloatBox

To position a free-floating box wherever you want. There is virtually no error-checking, so perhaps better keep your hands off. ;-)

 $image -> FloatBox(
        top =>$top, 
        bottom=>$bottom, 
        right=> $right, 
        left=> $top, 
        name=>"whatever_you_call_it", 
        background =>[color]
 );

GetTextSize

Get the boundig size of (rotated) text. Very useful to find out how big boxes need to be. ($width, $height) = $image -> GetTextSize( text => "Your Text", textsize => [number], rotate => [in degrees, may be negative as well] );

BoxSplit

 $image => BoxSplit (box => "name_of_parent", orientation=> "[vertical|horizontal]", count => $number_of_little_boxes);

Splits a box into "count" small boxes. This can be useful if you want to have spreadsheet-style segmentation.

Naming of little boxes: parent_[number, counting from 0]

In bitmap-land we only have integer-size-boxes. Therefore some boxes may be 1 pixel taller than others..

Example:

If the parent is "myBox", then the babies are named myBox_0, myBox_1, ...myBox_2635 (if you are crazy enough to have 2635 babies)

Text

For easy use: Better use 'Annotate' (inherited from ::Text) instead of 'Text'. Annotate reserves a box automatically while Text does not.

But of course, if you need / want full control, use 'Text'.

Put (rotated, antialized) text on a box. Takes a bunch of parameters, of which "text" and "textsize" are mandatory.

 $image -> Text(
        text =>         $text,
        textsize => [number],
        color=> "black",                                
        font => [font-file]
        rotate=>        [in degrees, may be negative as well],
        box =>  "free",
        align =>        [Left|Center|Right]",           #align is how multiline-text is aligned
        position =>[Center                              #position is how text will be positioned inside its box
                        NorthWest|
                        North|
                        NorthEast|
                        West|
                        SoutEast|
                        South|
                        SouthWest|
                        West],
        background=> [color]                            #rather for debugging
 );

Save

 $image -> Save($filename);

Save the image to file. There is no error-checking at the moment. You need to know yourself if your chosen library supports the desired file-type.

DrawRectangle

Rectangle without border:

 $image -> DrawRectangle (top => $top, bottom => $bottom, right => $right, left => $left, color => "color");

Rectangle with border:

 $image -> DrawRectangle (top => $top, bottom => $bottom, right => $right, left => $left, fill_color => "color", border_color => "color");

Draws a rectangle with the given sides. There are no rotated rectangles at the moment.

Internal methods:

(documentation for myself rather than the user)

rotation

To rotate a given point by any point. It takes the angle in degrees, which is very comfortable to me. If you want to rotate something, feel free to use it. :-)

 ($x, $y) = $image -> rotation($x, $y, $x_center, $y_center, $angle);

Checks if verbose is on and then prints messages. $image -> print_message("Text");

EXPORT

Nothing. Please use the object oriented interface.

SEE ALSO

Nowhere at the moment.

AUTHOR

Matthias Bloch, <lt>matthias at puffin ch<gt>

COPYRIGHT AND LICENSE

Copyright (C) 2008 by :m)

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.8.8 or, at your option, any later version of Perl 5 you may have available.