Re: optical encoder

Something like this should work (though I haven't tested it) with the current Rakudo Star release:

use v6;
use SVG;

my $r = 150 / 2;

my @parts = :circle[
    cx      => $r,
    cy      => $r,
    r       => $r,
    stlye   => 'fill:none; stroke: black; stroke-width: 1',
];

for 0, 2 ...^ 360 -> $degrees {
    my $rad = $degrees / 360 * 2 * pi;
    @parts.push: 'line' => [
        x1  => $r,
        y1  => $r,
        x2  => $r + $r * cos($rad),
        y2  => $r + $r * sin($rad),
    ];
}

say SVG.serialize:
    'svg' => [
        width  => 2 * $r,
        height => 2 * $r,
        @parts,
    ];
[download]

Run it as

perl6 circle.pl > circle.svg
[download]

and scale to your desired size.

Perl 6 - second systems done right

Comment on Re: optical encoder Select or Download Code

Replies are listed 'Best First'.
Re^2: optical encoder by jffry (Hermit) on Mar 16, 2012 at 17:07 UTC
The SVG module seems to misspell the `style` attribute as "stlye". From the output: `<svg xmlns="http://www.w3.org/2000/svg" xmlns:svg="http://www.w3.org/2 +000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" width="150 " height="150"><circle cx="75" cy="75" r="75" stlye="fill:none; stroke +: black; stroke-width: 1" />` [download] Visio 2007 also doesn't recognize the `xmlns:svg` attribute, but I'm going to assume that is Visio's fault.	[reply] [d/l]
Re^3: optical encoder by moritz (Cardinal) on Mar 16, 2012 at 17:23 UTC
The misspelling is right in the code I've posted, not in the module. In fact SVG.pm doesn't handle `style` specially in any way (though I've pondered it should). I've now actually tested the code, and this seems to work (the resulting SVG displays fine in firefox and inkscape). `use v6; use SVG; my $r = 150 / 2; my @parts = :circle[ cx => $r, cy => $r, r => $r, style => 'fill:none; stroke: black; stroke-width: 1', ]; for 0, 2 ...^ 360 -> $degrees { my $rad = $degrees / 360 * 2 * pi; @parts.push: 'line' => [ x1 => $r, y1 => $r, x2 => $r + $r * cos($rad), y2 => $r + $r * sin($rad), style => 'stroke: black; stroke-width: 1', ]; } say SVG.serialize: 'svg' => [ width => 2 * $r, height => 2 * $r, @parts, ];` [download] As for the `xmlns:svg` declaration, that just means that the `svg` XML namespace is set up as being interpreted as SVG. This allows you (in theory) to do fun stuff like embedding `<svg:rect ...>` elements straight into XHTML. But even for browsers that support it, it is only supported if the document is delivered as `application/xml+xhtml`, which is generally no fun, because most IE versions don't render such documents, but offer them for download. </rant> Perl 6 - second systems done right	[reply] [d/l] [select]