INHERITANCE
Math::Polygon::Transform is a Exporter
SYNOPSIS
my @poly = ( [1,2], [2,4], [5,7], [1, 2] );
my $area = polygon_transform resize => 3.14, @poly;
DESCRIPTION
This package contains polygon transformation algorithms.FUNCTIONS
 polygon_grid(%options, LISTof$points)

Snap the polygon points to grid points, where artifacts are removed.
OptionDefault raster 1.0

 raster => FLOAT
 The raster size, which determines the points to round to. The origin "[0,0]" is always on a gridpoint. When the raster value is zero, no transformation will take place.

 polygon_mirror(%options, LISTof$points)

Mirror the polygon in a line. Only one of the options can be provided.
Some programs call this ``flip'' or ``flop''.
OptionDefault b 0 line <undef> rc undef x undef y undef

 b => FLOAT
 Only used in combination with option "rc" to describe a line.
 line => [POINT, POINT]
 Alternative way to specify the mirror line. The "rc" and "b" are computed from the two points of the line.
 rc => FLOAT
 Description of the line which is used to mirror in. The line is "y= rc*x+b". The "rc" equals "dy/dx", the firing angle. If "undef" is explicitly specified then "b" is used as constant x: it's a vertical mirror.
 x => FLOAT
 Mirror in the line "x=value", which means that "y" stays unchanged.
 y => FLOAT
 Mirror in the line "y=value", which means that "x" stays unchanged.

 polygon_move(%options, LISTof$points)

Returns a list of points which are moved over the indicated distance
OptionDefault dx 0 dy 0

 dx => FLOAT
 Displacement in the horizontal direction.
 dy => FLOAT
 Displacement in the vertical direction.

 polygon_resize(%options, LISTof$points)

OptionDefault center [0,0] scale 1.0 xscale <scale> yscale <scale>

 center => POINT
 scale => FLOAT
 Resize the polygon with the indicated factor. When the factor is larger than 1, the resulting polygon with grow, when small it will be reduced in size. The scale will be respective from the center.
 xscale => FLOAT
 Specific scaling factor in the horizontal direction.
 yscale => FLOAT
 Specific scaling factor in the vertical direction.

 polygon_rotate(%options, LISTof$points)

Option Default center [0,0] degrees 0 radians 0

 center => POINT
 degrees => FLOAT
 specify rotation angle in degrees (between 180 and 360).
 radians => FLOAT
 specify rotation angle in rads (between pi and 2*pi)

 polygon_simplify(%options, LISTof$points)

Option Default max_points undef same 0.0001 slope undef

 max_points => INTEGER
 First, "same" and "slope" reduce the number of points. Then, if there are still more than the specified number of points left, the points with the widest angles will be removed until the specified maximum number is reached.
 same => FLOAT
 The distance between two points to be considered ``the same'' point. The value is used as radius of the circle.
 slope => FLOAT

With three points X(n),X(n+1),X(n+2), the point X(n+1) will be removed if
the length of the path over all three points is less than "slope" longer
than the direct path between X(n) and X(n+2).
The slope will not be removed around the starting point of the polygon. Removing points will change the area of the polygon.

DIAGNOSTICS
 Error: you need to specify 'x', 'y', 'rc', or 'line'
LICENSE
Copyrights 2004,20062014 by [Mark Overmeer]. For other contributors see ChangeLog.This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. See http://www.perl.com/perl/misc/Artistic.html