NAME
Math::FitRect - Resize one rect in to another while preserving aspect ratio.
SYNOPSIS
use Math::FitRect;
# This will return: {w=>40, h=>20, x=>0, y=>10}
my $rect = fit_rect( [80,40] => 40 );
# This will return: {w=>80, h=>40, x=>-19, y=>0}
my $rect = crop_rect( [80,40] => 40 );
DESCRIPTION
This module is very simple in its content but can save much time, much like other simplistic modules like Data::Pager. This module is useful for calculating what size you should resize images as for such things as thumbnails. If you find any other uses for "fitting rectangles in to each other" let the author know.
RECT TYPE
When a method needs a rectangle type it can be in one of the following forms:
1) $size
This is a single scalar holding an unsigned integer that specifys a square.
2) [ $w, $h ]
An array ref with the first entry being the width and the second the height.
3) { w=>$w, h=>$h }
Hash ref.
METHODS
The $rect1 and $rect2 in the proceding examples will use the following:
$rect1 = [20,10]; $rect2 = [40,8];
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fit_rect
my $new_rect1 = fit_rect( $rect1 => $rect2 );
Returns the following hash ref:
{ w=>16, h=>8, x=>12, y=>0 } = $new_rect1;
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Takes two rectangles and fits the first one inside the second one. The rectangle that will be returned will be a hash ref with a 'w' and 'h' parameter as well as 'x' and 'y' parameters which will specify any offset.
crop_rect
my $new_rect1 = crop_rect( $rect1 => $rect2 );
Returns the following hash ref:
{ w=>40, h=>20, x=>0, y=>-6 } = $new_rect1;
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Like the fit_rect function, crop_rect takes two rectangles as a parameter and it makes $rect1 completely fill $rect2. This can mean that the top and bottom (as in the diagram above) or the left and right get "chopped" off, or cropped as it is usually called. This method returns a has just like fit_rect.
PRIVATE METHODS
Do not use these methods directly as there is no garauntee that they work as documented or that they will work the same in future versions.
_calc_rect
_calc_rect( $type, $from_rect, $to_rect );
_normalize
$rect = _normalize( $rect );
Take in a rect in any of the supported formats and returns a hash ref with the following keys:
w - Width.
h - Height.
r - Aspect ratio. (w/h)
AUTHOR
Copyright (C) 2005 Aran Clary Deltac (CPAN: BLUEFEET)
This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.
Address bug reports and comments to: <aran@arandeltac.com>. When sending bug reports, please provide the version of Geo::Distance, the version of Perl, and the name and version of the operating system you are using. Patches are welcome if you are brave!