NAME
Transform::Canvas - Perl extension for blah blah blah
SYNOPSIS
use Transform::Canvas;
$t = Transform::Canvas->new(canvas=>[10,10,100,100],data=>[-100,-100,100,100]);
$r_x = [-100,-10, 0, 20, 40, 60, 80, 100];
$r_y = [-100,-10, 0, 20, 40, 60, 80, 100];
($pr_x,$pr_y) = $t->map($r_x,$r_y);DESCRIPTION
Stub documentation for Transform::Canvas, created by h2xs. It looks like the author of the extension was negligent enough to leave the stub unedited.
Blah blah blah.
EXPORT
None by default.
sub new (canvas => [x0 y0 x1 y1], data=>[x0 y0 x1 y1])
generate the conversion object through which all data points will be passed. NB: svg drawings use the painter's model and use a coordinate system which starts at the top, left corner of the document and has x-axis increasing to the right and y-axis increasing down.
The y-axis is inverted compared to mathematical representation systems which prefer y to increase up.
canvas:
x0 = paper-space minimum x value
y0 = paper-space maximum x value
x1 = paper-space minimum y value
y1 = paper-space maximum y value
data:
x0 = data-space minimum x value
y0 = data--space maximum x value
x1 = data-space minimum y value
y1 = data-space maximum y valuesub initialize
nothing to see. it's all over. move along.
prepareMap
prepare the transformation space for the conversions; Currently only handles linear transformations, but this is a perfect candidate for non-spacial transforms... Maybe Kake or Jo have ideas...
i wish i had my math texts with me and i was not on a train for this...
map($x,$y)
Map an array or a value of the x,y data axes to the x,y canvas axes
mapX
Map an array or a value of the x data axis to the x canvas axis
mapY
Map an array or a value of the y data axis to the y canvas axis
SEE ALSO
SVG SVG::Parser SVG::DOM SVG::Element SVG::Graph SVG::Extension
AUTHOR
Ronan Oger, <ronan@roasp.com<gt>
COPYRIGHT AND LICENSE
Copyright (C) 2004 by Ronan Oger
This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.8.3 or, at your option, any later version of Perl 5 you may have available.