Math::Polygon::Transform  Polygon transformation
Math::Polygon::Transform
is a Exporter
my @poly = ( [1,2], [2,4], [5,7], [1, 2] );
my $area = polygon_transform resize => 3.14, @poly;
This package contains polygon transformation algorithms.
 polygon_grid(%options, @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, @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, @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, @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, @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, @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.
 Error: you need to specify 'x', 'y', 'rc', or 'line'
This module is part of MathPolygon distribution version 1.10, built on January
03, 2018. Website:
http://perl.overmeer.net/CPAN/
Copyrights 20042018 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://dev.perl.org/licenses/