Imager - Draw Graphical Elements

Perl Tutorials - Herong's Tutorial Examples

∟Imager - Draw Graphical Elements

This section provides a tutorial example on how to draw graphical elements using line(), box(), circle() functions of the Perl Imager module.

With the Imager module, you can add graphical elements to an image using drawing functions like: line(), box(), circle(), etc..

1. Write a Perl script to create an image with some graphical elements added and save it to Imager-Graphics.bmp:

#- Imager-Draw-Graphics.pl
#- Copyright (c) HerongYang.com. All Rights Reserved.

use Imager;
$img = Imager->new(xsize=>400, ysize=>400);

print "Drawing a box...\n";
$img->box(xmin=>50,ymin=>50, xmax=>350,ymax=>350, color=>'#0000ff',
      filled=>1);

print "Drawing a circle...\n";
$img->circle(x=>200,y=>200,r=>100, color=>'#00ff00', filled=>1);

print "Drawing 2 lines...\n";
$img->line(x1=>0,y1=>0, x2=>400,y2=>400, color=>'#ff0000');
$img->line(x1=>400,y1=>0, x2=>0,y2=>400, color=>'#ff0000');

$file = "Imager-Graphics.bmp";
$img->write(file=>$file) or
      die $img->errstr;
print "Image saved:\n";
print "   File: $file\n";

2. Run the above script:

herong$ perl Imager-Draw-Graphics.pl

Drawing a box...
Drawing a circle...
Drawing 2 lines...
Image saved:
   File: Imager-Graphics.bmp

3. View Imager-Graphics.bmp. You see a nice image.

Table of Contents

About This Book

Perl on Linux Systems

ActivePerl on Windows Systems

Data Types: Values and Variables

Expressions, Operations and Simple Statements

User Defined Subroutines

Perl Built-in Debugger

Name Spaces and Perl Module Files

Symbolic (or Soft) References

Hard References - Addresses of Memory Objects

Objects (or References) and Classes (or Packages)

Typeglob and Importing Identifiers from Other Packages

String Built-in Functions and Performance

File Handles and Data Input/Output

Open Files in Binary Mode

Open Directories and Read File Names

File System Functions and Operations

►Image and Picture Processing

Imager - Create and Save Image

►Imager - Draw Graphical Elements

Imager - Convert Image File Format

Imager::File::PNG - PNG File Format

Install LIBPNG from Source Code

Install Imager::File::PNG Manually

Install PerlMagick from Source Code

Using DBM Database Files

Using MySQL Database Server

Socket Communication Over the Internet

XML::Simple Module - XML Parser and Generator

XML Communication Model

SOAP::Lite - SOAP Server-Client Communication Module

Perl Programs as IIS Server CGI Scripts

CGI (Common Gateway Interface)

XML-RPC - Remote Procedure Call with XML and HTTP

RPC::XML - Perl Implementation of XML-RPC

Integrating Perl with Apache Web Server

CGI.pm Module for Building Web Pages

LWP::UserAgent and Web Site Testing

Converting Perl Script to Executable Binary

Managing Perl Engine and Modules on macOS

Archived Tutorials

References

Full Version in PDF/EPUB