Perl Graphics Programming

Name

Draw( )

Synopsis

$image->Draw(primitive=>string,
             points=>string,
             method=>{Point, Replace, Floodfill, FillToBorder, Reset},
             stroke=>colorname,
             fill=>colorname,
             tile=>image_object,
             strokewidth=>float,
             antialias=>boolean,
             bordercolor=>colorname,
             affine=>float_array,
             x=>float, y=>float,
             translate=>geometry,
             scale=>geometry, rotate=>float,
             skewX=>float, skewY=>float)

The Draw( ) method allows you to draw anywhere on an image with one of many graphics primitives. The points parameter indicates the position to start drawing and must be a string of one or more coordinates, depending on the primitive being used. A coordinate string can look like any of these:

"3,5"                       # a single point
"10,10 20,20"               # two coordinates for a line, rectangle or circle
"40,40 80,80 50,80 90,40"   # four points for a polygon

Choose one of the following primitive types:

Bezier

This draws a curved line whose points are written as a cubic Bezier curve, where each curved segment is defined by two points and a single control point. For example:

$image->Draw(primitive=>'Bezier',
             points=> "350,475 250,475 250,400 ".
                      "250,350 325,350 325,400",
             stroke=>'red',
             antialias=>1,
             linewidth=>1
);

Circle

The Circle primitive uses the first coordinate to define its center and the second coordinate to define a point on the edge. For example, to draw a circle centered at (100,100) that extends to (150,150), use:

# draw a fat circle of radius 50 centered at 100,100
$image->Draw(primitive=>'Circle',
             points=>'100,100 150,150',
             linewidth=>10);