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NAME

SVG - perl extention for generating SVG (scalable-vector-graphics)

METHODS

attrib animate cdata circle defs desc ellipse fe get_path group image line mouseaction new path polygon rectangle script style SVG text title use xmlify

SYNOPSIS

  use SVG;
  use strict;
  use CGI ':new :header';
  my $p = CGI->new;
  $| = 1;

  my $svg= SVG->new(width=>200,height=>200); 

  my $y=$svg->group( id     =>  'group_y',
                     style  =>  {stroke=>'red', fill=>'green'} );

  my $z=$svg->tag('g',  id=>'group_z',
                        style=>{ stroke=>'rgb(100,200,50)', 
                                 fill=>'rgb(10,100,150)'} );

 
  $y->circle(cx=>100,
             cy=>100,
             r=>50, 
             id=>'circle_y',);

  $z->tag('circle',cx=>50,
             cy=>50,
             r=>100, 
             id=>'circle_z',);
  
  # an anchor with a rectangle within group within group z

  my $k = $z -> anchor(
                     -href   => 'http://test.hackmare.com/',
                     -target => 'new_window_0') -> 
                      rectangle ( x=>20,
                                      y=>50,
                                      width=>20,
                                      height=>30,
                                      rx=>10,
                                      ry=>5,
                                      id=>'rect_z',);
  

  print $p->header('image/svg-xml');
  print $svg->xmlify;

DESCRIPTION

SVG is a 100% perl module which generates a nested data structure which contains the DOM representation of an SVG image. Using SV, You can generate SVG objects, embed other SVG instances within it, access the DOM object, create and access javascript, and generate SMIL animation content.

EXPORT

None

AUTHOR

Ronan Oger, ronan@roasp.com

SEE ALSO

perl(1) SVG::Utils http://roasp.com/

SVG

$svg = SVG->new %properties

Creates a new svg object.

$xmlstring = $svg->xmlify %attributes

Returns xml representation of svg document.

XML Declaration

 Name       Default Value
 version         '1.0'
 encoding        'UTF-8'
 standalone      'yes'
 namespace       'svg' 
 -inline         '0'         If '1', then this is an inline document
                             and is intended for use inside an XML document.

 identifier      '-//W3C//DTD SVG 1.0//EN';
 dtd             'http://www.w3.org/TR/2001/REC-SVG-20010904/DTD/svg10.dtd'  
$tag = $svg->tag $name, %properties

Creates element $name with %properties.

Example:

        $tag = $svg->tag('g', transform=>'rotate(-45)');
$tag = $svg->anchor %properties

create a url anchor tag. requires a child drawn object or group element.

Example: # a complete anchor with a child tag $tag = $svg->anchor( -href=>'http://here.com/some/simpler/svg.svg' ); $tag->circle(cx=>10,cy=>10,r=>1);

        # alternate tag definitions
        $tag = $svg->anchor(
                -href   => 'http://somewhere.org/some/other/page.html',
                -target => 'new_window'
        );

        $tag = $svg->anchor(
                -href   => 'http://someotherwhere.net',
                -target => '_top'
        );
$tag = $svg->circle %properties

draw a circle at cx,xy with radius r

Example:

        $tag = $svg->circle(    cx=>4
                                cy=>2
                                r=>1,);
$tag = $svg->ellipse %properties

draw an ellipse at cx,cy with radii rx,ry

Example:

        $tag = $svg->ellipse(cx=>10
                      cy=>10
                      rx=>5
                      ry=>7
                      id=>'ellipse',
                      style=>{'stroke'=>'red',
                              'fill'=>'green'
                              'stroke-width'=>'4'
                              'stroke-opacity'=>'0.5',
                              'fill-opacity'=>'0.2'});
$tag = $svg->rectangle %properties

draw a rectangle at (x,y) with width 'width' and height 'height' and side radii 'rx' and 'ry'

Example:

        $tag = $svg->rectangle( x=>10,
                                y=>20,
                                width=>4,
                                height=>5,
                                rx=>5.2,
                                ry=>2.4,
                                id=>'rect_1',);
$tag = $svg->image %properties

draw an image at (x,y) with width 'width' and height 'height' linked to image resource '-href'.

Example:

        $tag = $svg->image(     x=>100,
                                y=>100,
                                width=>300,
                                height=>200,
                          '-href'=>"image.png"
                                id=>'image_1',);

        $tag = $svg->image(     x=>100,
                      y=>100,
                      width=>300,
                      height=>200,
                      '-href'=>"image.svg"
                      id=>'image_1',);

Outputs:

 <image xlink:href="image.png" x="100" y="100" width="300" height="200"/>
$tag = $svg->use %properties

Retrieve the content from an entity within an SVG document and apply it at (x,y) with width 'width' and height 'height' linked to image resource '-href'.

Example:

        $tag = $svg->use(       x=>100,
                    y=>100,
                    width=>300,
                    height=>200,
                    '-href'=>"image.svg#image_1"
                    id=>'image_1',);

Outputs:

   <use xlink:href="image.svg#image_1"  x="100" y="100" width="300" height="200"/>

According to the SVG specification, the 'use' element in SVG can point to a single element within an external SVG file.

SEE ALSO:

anchor.

$tag = $svg->polygon %properties

draw an n-sided polygon with vertices at points defined by string 'x1 y1,x2 y2,x3 y3,...xy yn'. use method get_path to generate the string.

Example:

  # a five-sided polygon

  my $xv = [0,2,4,5,1];

  my $yv = [0,0,2,7,5];

  $points = $a->get_path(x=>$xv,
                          y=>$yv,
                        -type=>'polygon',);

  $c = $a->polygon (%$points,
                    id=>'pgon1',
                    style=>\%polygon_style);

SEE ALSO:

polyline.

path.

get_path.

$tag = $svg->polyline %properties

draw an n-point polyline with points defined by string 'x1 y1,x2 y2,...xn yn'. use method get_path to generate the vertices from two array references.

Example:

  # a 10-pointsaw-tooth pattern

  my $xv = [0,1,2,3,4,5,6,7,8,9];

  my $yv = [0,1,0,1,0,1,0,1,0,1];

  $points = $a->get_path(x=>$xv,
                          y=>$yv,
                        -type=>'polyline',
                        -closed=>'true'); #specify that the polyline is closed.

  my $tag = $a->polyline (%$points,
                    id=>'pline_1',
                    style=>{'fill-opacity'=>0,
                            'stroke-color'=>'rgb(250,123,23)'}
                    );

SEE ALSO:

get_path.

$tag = $svg->line %properties

draw a straight line between two points (x1,y1),(x2,y2).

Example:

  my $tag = $svg->line( id=>'l1',
                        x1=>0,
                        y1=>0,
                        x2=>10,
                        y2=>10,);

SEE ALSO:

polyline.

$text = $svg->text %properties

define the container for a text string to be drawn in the image.

Example:

  my $text = $svg->text( id=>'l1',x=>10
                        y=>10,) -> cdata('hello, world');

SEE ALSO:

desc.

cdata.

$tag = $svg->title %properties

generate the description of the image.

Example:

  my $tag = $svg->title( id=>'root-title')->cdata('hello this is the title');
$tag = $svg->desc %properties

generate the description of the image.

Example:

  my $tag = $svg->desc( id=>'root-desc')->cdata('hello this is a description');
$tag = $svg->script %properties

Example:

  my $tag = $svg->script(type=>"text/ecmascript");

  # populate the script tag with cdata
  # be careful to manage the javascript line ends.
  # qq|text| or qq§text§ where text is the script 
  # works well for this.

  $tag->cdata(qq|function d(){//simple display function
        for(cnt = 0; cnt < d.length; cnt++)
          document.write(d[cnt]);//end for loop
        document.write("<BR>");//write a line break
      }//end function|);
$tag = $svg->path %properties

Example:

  # a 10-pointsaw-tooth pattern drawn with a path definition

  my $xv = [0,1,2,3,4,5,6,7,8,9];

  my $yv = [0,1,0,1,0,1,0,1,0,1];

  $points = $a->get_path(x=>$xv,
                          y=>$yv,
                        -type=>'path',
                        -closed=>'true'); #specify that the polyline is closed.

  $tag = $svg->path (%$points,
                    id=>'pline_1',
                    style=>{'fill-opacity'=>0,
                            'fill-color'=>'green',
                            'stroke-color'=>'rgb(250,123,23)'}
                    );

SEE ALSO:

get_path.

$path = $svg->get_path %properties

A method which returns the text string of points correctly formatted to be incorporated into the multi-point SVG drawing object definitions (path, polyline, polygon)

 input:

 output: a hash reference consisting of the following key-value pair:
 points = the appropriate points-definition string
 type = path|polygon|polyline
 -relative = 1 (points define relative position rather than absolute position)
 -closed = 1 (close the curve - path and polygon only)

Example:

 #generate an open path definition for a path.
 my ($points,$p);
 $points = $svg->get_path(x=>\@x,y=>\@y,-relative=>1,type=>'path');
 
 #add the path to the SVG document 
 my $p = $svg->path( %$path,
                  style=>\%style_definition); 

 #generate an closed path definition for a a polyline.
 $points = $svg->get_path( x=>\@x,
                        y=>\@y,
                        -relative=>1,
                        -type=>'polyline',
                        -closed=>1); # generate a closed path definition for a polyline

 # add the polyline to the SVG document
 $p = $svg->polyline (%$points,
                    id=>'pline1',);
animate(\%params)

Generate an SMIL animation tag. This is allowed within any of the nonempty tags. Refer to the W3C for detailed information on the subtleties of the animate SMIL commands.

 inputs: -method = Transform | Motion | Color
$tag = $svg->group %properties

define a group of objects with common properties. groups can have style, animation, filters, transformations, and mouse actions assigned to them.

Example:

        $tag = $svg->group(
                id        => 'xvs000248',
                style     => {
                        'font'      => [ qw( Arial Helvetica sans ) ],
                        'font-size' => 10,
                        'fill'      => 'red',
                },
                transform => 'rotate(-45)'
        );
$tag = $svg->defs %properties

define a definition segment. A Defs requires children

Example:

        $tag = $svg->defs(id  =>  'def_con_one',);
$svg->style %styledef

Sets/Adds style-definition for the following objects being created.

Style definitions apply to an object and all its children for all properties for which the value of the property is not redefined by the child.

$svg->mouseaction %styledef

Sets/Adds mouse action definitions for tag

$svg->mouseaction %styledef

Sets/Adds mouse action definitions.

$svg->attrib $name, $val
$svg->attrib $name, \@val
$svg->attrib $name, \%val

Sets attribute to val for a tag. }

$svg->cdata $text

Sets cdata to $text.

Example:

        $svg->text(style=>{'font'=>'Arial','font-size'=>20})->cdata('SVG.pm is a perl module on CPAN!');

  my $text = $svg->text(style=>{'font'=>'Arial','font-size'=>20});
  $text->cdata('SVG.pm is a perl module on CPAN!');

Result:

        E<lt>text style="font: Arial; font-size: 20" E<gt>SVG.pm is a perl module on CPAN!E<lt>/text E<gt>

  SEE ALSO:

  L<desc>.

  L<text>.

  L<script>.
$tag = $svg->fe %properties

Generate a filter element

Example:

        $tag = $svg->fe(-TYPE => 
                              id        => 'filter_1',
                              style     => {'font'      => [ qw( Arial Helvetica sans ) ],
                                'font-size' => 10,
                                'fill'      => 'red',},
                        transform => 'rotate(-45)' );

h1<The following elements have not yet been implemented as of this release:>

Although these elements do not have an explicit constructor, they can be constructed using the $svg->tag(%attra) generic element.

not-yet implemented elements:

              altGlyph 
              altGlyphDef 
              altGlyphItem 
              clipPath 
              color-profile 
              cursor 
              definition-src 
              defs 
              feBlend 
              feColorMatrix 
              feComponentTransfer 
              feComposite 
              feConvolveMatrix 
              feDiffuseLighting 
              feDisplacementMap 
              feDistantLight 
              feFlood 
              feFuncA 
              feFuncB 
              feFuncG 
              feFuncR 
              feGaussianBlur 
              feImage 
              feMerge 
              feMergeNode 
              feMorphology 
              feOffset 
              fePointLight 
              feSpecularLighting 
              feSpotLight 
              feTile 
              feTurbulence 
              font-face-format 
              font-face-name 
              font-face-src 
              font-face-uri 
              foreignObject 
              glyph 
              glyphRef 
              hkern 
              marker 
              mask 
              metadata 
              missing-glyph 
              mpath 
              pattern 
              radialGradient 
              set 
              stop 
              switch 
              symbol 
              textPath 
              tref 
              tspan 
              view 
              vkern 

2 POD Errors

The following errors were encountered while parsing the POD:

Around line 101:

'=item' outside of any '=over'

=over without closing =back

Around line 589:

Non-ASCII character seen before =encoding in 'qq§text§'. Assuming CP1252