Programming Web Graphics with Perl and GNU Softwar

Name

addArc( ) — add an arc to the object

Synopsis

$e->addArc( points => [ $x, $y, $r, $startangle, $endangle],
               linewidth => $linewidth,
               linetint => $linetint,
               filltint => $filltint )

The addArc( ) method will add an arc segment to the Elements object. It takes up to four parameters, of which only the points parameter is required:

points

A points parameter is required, consisting of a reference to a list specifying the center coordinate, the radius of the arc, and two numbers specifying the starting angle and the ending angle describing the sweep of the arc. For example:

addArc(points=>[50,50,25,0,360])

would add a complete circle centered at 50, 50 with a radius of 25. Note that the list of points is in the same form as the PostScript arc function.

linewidth

The linewidth attribute can be used to specify the point size of the line with which the arc is to be stroked. If no value is given, the default line width is 1 point.

linetint

The linetint attribute should be a number between and 1 representing a percentage of gray, with 1 as black and as white. Therefore, .8 would be the equivalent of a 20% gray screen. If no value is given, the line will be stroked in black (linetint=1).

filltint

The filltint attribute should be either -1 or a number between and 1 representing a percentage of gray, with 1 as black and as white. If the value is -1, the shape will not be filled in; it will be transparent. Otherwise, the shape will be opaque. The default value is -1.