Programming Web Graphics with Perl and GNU Softwar

Name

setBrush( ) — assign a brush to an image

Synopsis

GD::Image::setBrush(image)

The drawing commands available through GD can be called with either a solid color or with a special brush that is accessed via the gdBrushed constant. This brush is simply another image that must be created or read in from another GIF file. The setBrush( ) method assigns a particular image as the current brush for drawing within another image. To draw with a brush follow these five steps:

1. Create a new image object for the brush, or read the brush from a GIF file. Here we will create a new square 20 × 20 pixel brush:

   my $brush = new GD::Image(20, 20);

2. If you are creating a new brush with the GD drawing commands, allocate a color for the brush and draw the brush shape. In this case, the brush is a red circle:

   my $red = $brush->allocateColor(255, 0, 0);
   $brush->arc(10, 10, 20, 20, 0, 360, $red);

3. If you are creating an irregularly shaped brush, set the background color of the brush with the transparent( ) method so that the brush does not overwrite its own path:

   my $white = $brush->allocateColor(255, 255, 255);
   $brush->transparent($white);

4. Assign the brush to the image you want to draw on:

   $image->setBrush($brush);

5. Call a drawing command with gdBrushed as the color parameter to use the brush:

   $image->line(0, 0, 50, 50, gdBrushed);