Free and Open Source 2D Animation Software for Linux

After featuring some of the best Free and Open Source 3D animation software, it's time to take a look at some 2D computer graphics program for Linux users who are into creating two-dimensional models. These free 2D animation software is as capable as those that are commercially available so do take time to try them first before emptying your wallet.

Here are a few Free and Open Source 2D animation software for Linux that you may like:

Synfig
Synfig is a 2D vector graphics and timeline-based computer animation program that was originally the custom animation platform for the now discontinued Voria Studios. The main goal of the project is to create a program that is capable of producing "feature-film quality animation with fewer people and resources." The program offers an alternative to manual tweening so that the animator doesn't have to draw each and every frame. Synfig is capable of simulating soft-shading using curved gradients within an area so that the animator doesn't have to draw shading into every single frame.

Learn more about Synfig HERE

KToon
KToon is a 2D Animation Toolkit designed by Toonka Films animators for aspiring animators. It is designed to function in a similar way to popular proprietary animation packages, like Macromedia Flash. It currently lacks a scripting language like Macromedia's ActionScript, but it can export movies as AVI files and Flash animations. KToon uses OpenGL and Qt toolkit as programming resources.

Learn more about KToon HERE

Pencil
Pencil is a drawing and 2D animation software that is written in C++ and is based on QT. It uses a unique bitmap/vector drawing interface to produce simple 2D graphics as well as animation. Pencil is also available for Windows, Mac, and BSD.

Learn more about Pencil HERE

If you know of other free and open source 2D animation software that I failed to include here, please share them with us via comment.

8 of the Best Online Backup Services for Linux

A remote or online backup service has become quite an important tool for those of us who travel a lot and require some of our files on the cloud for easy access anytime and any place with Internet connection. It can also be useful for users who need to sync some of their data across two or more computer machines most of the time.

An online backup system is usually built around client software that runs on a schedule, but some can work continuously, backing up files as they are changed. It collects, compresses, encrypts, and transfers the files to the remote backup service provider's servers.

I have here a list of some of the best online or remote backup services for Linux. Most of these tools/services can backup and synchronize files across different operating system platforms, which should be really handy if you are using more than one OS.


Dropbox
At the moment, Dropbox is my favorite online backup service for its simplicity and ease of use. It is cross-platform and has desktop clients for Linux, Mac, and Windows, but it can also be used through its web-based client. Dropbox also has native applications for popular handheld devices such as Android, BlackBerry, iPhone, iPad, and a few others. With Dropbox, you can just drop or copy any file into a designated folder that is then synced to the cloud and to any other of the user's computers and devices with the Dropbox app. You may also upload files manually through a web browser. Dropbox provides 2 GB of free online storage but a paid option is available for bigger storage size and for other premium services.


ZumoDrive
ZumoDrive is a file synchronization and storage service that enables users to store and sync files online and between computers using their HybridCloud storage solution. Like Dropbox, it has cross-platform clients for Windows, Mac, Linux, iPhone, and Android, and also has a web browser interface. Files in the ZumoDrive virtual disk can be shared with other ZumoDrive users. The ZumoDrive service is unique when compared to other file sync and storage services in the sense that it appears local to the filesystem and can be streamed from the cloud on demand. Users can have 2 GB of free storage space and may upgrade to paid plans ranging from 10 GB to 500 GB for a monthly subscription fee.


ADrive
ADrive is an online backup, file sharing, and data storage service that provides an amazing 50 GB of free storage (largest amount of free storage and backup on the Internet) for its Basic Account holders. Paid subscribers can have additional storage and services like multiple connections, FTP with timestamp support, WebDAV, and file history recovery. ADrive has an easy-to-use browser-based file manage that is compatible with Windows, Linux, and Mac.


Ubuntu One
Ubuntu One is Ubuntu's very own storage application and service with a client application available only for Ubuntu 9.04 and newer. The client side is written in Python and uses Twisted for its low-level networking and Protocol Buffers for protocol description. What makes Ubuntu One different from other similar service providers are additional features like its integration with other applications such as Evolution and Tomboy. Ubuntu One offers 2 GB of free storage but users may upgrade to 50 GB for $10 per month.


SpiderOak
SpiderOak is a cross-platform online backup and sharing tool that provides users with off-site server for data management. It differentiates itself from competition in administration of encryption and in automatic de-duplication of data. While some services can only backup a specified folder like in DropBox, SpiderOak allows you to backup any given folder from your computer. It also features a Fault-Tolerant Design, hence no file is ever removed from a user account before he manually does it through the client. SpiderOak offers a free 2 GB account, as well as a paid subscription for premium services.


Wuala
Wuala is a social distributed file-system-like online storage service that allows users to have as much online storage as they give to other Wuala users. Its interface is comparable to a file manager but afar from the common file operations, it allows the user to easily share files with friends, in groups or with the rest of the world. Every user starts with 1GB of online storage but can get more space either by trading local disk space, by buying additional storage, by referring it to their friends or by using the promotion codes.


Jungle Disk
Jungle Disk is an online backup service that was highlighted by Amazon as one of the earliest S3 clients. It has the capability to periodically back up selected files or folders, and provides a local webdav server and a local web interface that synchronize to the user's S3 account, alternatively encrypting backed up data on the client side. The basic Jungle Disk software is sold as a monthly subscription model. It provides a hosted web interface and more advanced backup functionality for a monthly fee.


CrashPlan
CrashPlan is a a cross-platform backup software that allows users to back up their data to an offsite data center, desktop computers belonging to friends and family, as well as to shared folders. For personal use, a free version is available that offers basic functionality. For enterprise, CrashPlan Pro is available with a bunch of powerful features. Data are encrypted using 128-bit encryption for the personal CrashPlan, while 448-bit Blowfish encryption is used for CrashPlan Pro.


There are probably other good online backup services for Linux, so it's up to you our dear readers to share them with us via comment.

You may also check out our list of backup software for Linux, and our other collection of Linux backup software.

7 (More) Best Free/Open-source Backup Software for Linux

Before, we have featured here some of the best Free and Open Soure backup software for Linux. As I've already explained, a backup software is essential for recovering important files when disaster happens. Since there are still several excellent free and open source backup software that I failed to mention the last time, I decided to once again gather another list of some of the best backup software that are available for Linux.

BackupPC
BackupPC is a Disk-to-disk backup software suite that is considered as one of the most popular free and open-source backup software. It has a web-based frontend with no need for client as the server is itself a client for several protocols, which are handled by other services native to the client OS. BackupPC is using a combination of hard links to reduce the total disk space utilized for files. During the first full backup, each and every file is transferred to the backend, optionally compressed, and then compared. All similar files are hard linked and use only one additional directory entry.



Areca Backup
Areca Backup is a personal file backup software written in Java. It includes a backup engine, along with a graphical user interface and a command-line interface. It has been designed to be as simple as possible to set up with no complex configuration files to edit. It is also flexible since it can use advanced backup modes (like "delta backup") or simply produce a "basic" copy of your source files as a standard directory or zip archive (readable by WinZip or other archivers). Areca Backup will also allow you to interact with your archives and the files they contain. You can track different versions of a specific file, browse your archives, recover or view specific files, and merge a set of archives.



DirSync Pro
DirSync Pro (Directory Synchronize Pro) as described from its project website is a small, but powerful utility for file and folder synchronization. It can be used to synchronize the content of one or many folders recursively. DirSync Pro offers a graphical user interface from which the user can manage and run multiple synchronization tasks, and you can also use it via the command line that makes it very flexible for running in batches. It supports local folder to folder synchronization, but does not allow synchronization via FTP. DirSync Pro is self-contained within its own directory, and is therefore fully portable.

luckyBackup

luckyBackup is a fast and reliable free backup application that has a graphical user interface (GUI) based on the cross platform Qt libraries and is not fundamentally console based or web based as many of the clients from the list of backup software are. Its GUI is already translated in many languages and is notable for its availability directly from the repositories of all major Linux distributions including Debian, Ubuntu, openSuse, Fedora, Mandriva, Arch, Slackware, and Gentoo. luckyBackup shares the data differencing and copying tool, rsync, with BackupPC, rdiff-backup, and several others.

Partimage
Partimage is a free and open-source disk backup software. It can save partitions in many formats to a disk image. Using Partimage, partitions can be saved across the network using the Partimage network support, or using Samba / NFS (Network File Systems). This provides the capability to perform a hard disk partition recovery after a disk crash. Aside from running as part of your normal system, Partimage can be loaded as a stand-alone from the live SystemRescueCd, which is helpful when the operating system cannot be started. SystemRescueCd is packed with data recovery software for Linux that you may need.

Mondo Rescue
Mondo Rescue is a reliable free disaster recovery solution. It backs up your Linux server or workstation to tape, CD-R, CD-RW, DVD-R(W), DVD+R(W), NFS or hard disk partition. Mondo Rescue supports several filesystems including LVM 1/2, RAID, ext2, ext3, ext4, JFS, XFS, ReiserFS, VFAT, and can support additional filesystems easily. It also offers support for software raid as well as most hardware raid controllers. Mondo runs on all major Linux distributions such as Ubuntu, RedHat, SuSE, Mandriva, Debian, and Gentoo. However, you can use it to backup non-Linux partitions like NTFS if needed.

tar
tar is a file archiver that is designed to store and extract files from an archive file known as a tarfile. A tarfile may be made on a tape drive; however, it is also common to write a tarfile to a normal file. Originally created to be written directly to sequential I/O devices for tape backup purposes, it is now primarily used to collect many files into one larger file for distribution or archiving, while preserving file system information such as user and group permissions, dates, and directory structures.

7 Best Free and Open Source Content Management Systems (CMS)

A content management system (CMS) is a software used to simplify the management and publication of HTML content such as documents and images. It provides authoring and other tools designed to allow users with little technical knowledge of programming languages or markup languages to create and manage content with relative ease. Most web CMS use a database to store content, metadata, or artifacts that might be needed by the system. Content is commonly stored as XML, to facilitate, reuse, and enable flexible presentation options.

For those of you who are interested, I have here a list of some of the most well-known and perhaps the best free and open source content management systems (CMS) available:


WordPress
WordPress is widely considered as the most popular blog publishing application, and is used by over 2% of the 10,000 biggest websites. It is powered by PHP and MySQL and offers many features including a plugin architecture and a templating system. The templating system includes widgets that can be rearranged without editing PHP or HTML code, as well as themes that can be installed and switched between. WordPress features integrated link management; a search engine-friendly, clean permalink structure; the ability to assign nested, multiple categories to articles; and support for tagging of posts and articles. Automatic filters that provide for proper formatting and styling of text in articles are also included. WordPress has a rich plugin architecture that allows users and developers to extend its functionality beyond the features that come as part of the base install.


Drupal
Drupal is a free and open source content management system (CMS) written in PHP. It is utilized as a back-end system for at least 1% of all websites worldwide, which ranges from small personal blogs to large corporate and political sites that includes whitehouse.gov and data.gov.uk. Although Drupal offers a sophisticated programming interface for developers, no programming skills are required for basic website installation and administration. Its standard release, known as Drupal core, contains basic features common to most CMSs. These include the ability to register and maintain individual user accounts within a role-based permission/privilege system, create and manage menus, RSS-feeds, customize page layout, perform logging, and administer the system. Drupal was also designed to allow new features and custom behavior to be added to extend Drupal's core capabilities via installation of plug-in modules.


Joomla!
Joomla! is an open source content management system (CMS) platform for publishing content on the internet along with a Model–view–controller (MVC) Web application framework. It is written in PHP, stores data in MySQL, and contains features such as page caching, RSS feeds, printable versions of pages, news flashes, blogs, polls, search, and support for language internationalization. Inside its first year of release, Joomla was downloaded 2.5 million times. As of today, over 4,000 free and commercial plug-ins are available for Joomla.


Movable Type
Movable Type is a weblog publishing system written in Perl. It supports storage of the weblog's content and associated data within MySQL, PostgreSQL, and SQLite. Movable Type optionally supports LDAP for user and group management and automatic blog provisioning. Features: Multiple weblogs; Standalone content pages; Asset and File Manager; User and user role management; Customizable templates; Tags; Categories, sub-categories and multiple categories for articles; TrackBack; Bookmarklets.


Plone
Plone is a content management system built on top of the Zope application server. Plone can be used for in principle any kind of website, including blogs, webshops, and internal websites. It is also well positioned to be used as a document publishing system and groupware collaboration tool. The strengths of Plone are its flexible and adaptable workflow, very good security, extensibility, high usability and flexibility. It excels when compared to other content-management systems in standards conformance, access control, internationalization, aggregation, user-generated content, micro-applications, active user groups and value. All of Plone's features are customizable, and free add-ons are available from the Plone website.


PHP-Fusion
PHP-Fusion is a light-weight open-source content management system (CMS) written in PHP. It uses a MySQL database to store a web site's content and comes with a simple but comprehensive administration system. PHP-Fusion includes features common in many other CMS packages such as easy integration of articles, forums, photogallery, web links, downloads, polls, shoutbox, search, and themes. It also offers users the opportunity to expand the standard packages with so-called "infusions". These infusions can be easily uploaded, installed, and managed.


XOOPS
XOOPS (eXtensible Object Oriented Portal System) is a CMS written in PHP that uses a modular architecture allowing users to customize, update and theme their websites. It aims to serve as a web framework for use by small, medium and large sites, through the installation of modules. For example, a small XOOPS installation can be used as a personal weblog or journal, but this can be expanded upon and customized, for example users might add the appropriate modules to store content in news, forums, downloads, and more.

If you have other favorite web content management systems that I failed to mention above, you can share them with us via comment.

12 of the Best Media Players for Linux

One of the many perks of being a Linux user is that you have plenty of excellent software to choose from. This is especially true if you are in search for an essential application like a media player because there are definitely loads of options. However, this could sometimes be a disadvantage particularly to new-to-Linux users for the reason that they could get overwhelmed with the many choices they have.

To somehow guide those who are still looking for a media player that will suit their needs, I have put together a list that I hope will help. Take your pick from 12 of the best and certified quality media players for Linux.

Banshee
Banshee is a free audio player for GNU/Linux operating systems that is built upon Mono and Gtk#. It uses the GStreamer multimedia platform for encoding, and decoding various music formats, including Ogg Vorbis, MP3 and FLAC. Banshee can play, import and burn audio CDs, but it can not synchronize music with any portable media players, including Apple's iPod and Creative Zen players, in the current version. Music stored on the iPod can be played without synchronization, and album art stored in the Banshee library is transferred to the iPod. Support for MTP and PlaysForSure devices, as well as the Rio Karma player is planned for the near future.


Rhythmbox
Rhythmbox is an audio player that plays and helps organize digital music. Originally inspired by Apple's iTunes, it is free software, designed to work well under the GNOME Desktop using the GStreamer media framework. It is currently under active development.

Playback from a variety of digital music sources is supported, excluding MIDI. The most common playback is music stored locally as files on the computer (the 'Library'). Rhythmbox supports playing streamed Internet radio and podcasts as well. The Replay Gain standard is supported.


Totem
Totem is a free software media player (audio and video) for the GNOME computer desktop environment that runs on Linux, Solaris, BSD and other Unix and Unix-like systems. It is officially included in GNOME starting from version 2.10 (released in March 2005), but de facto it was already included in most GNOME environments. The default backend is GStreamer framework but Totem can also use xine libraries. Totem is included as the default media player in many desktop Linux distributions, including Ubuntu, Mandriva Linux and others.

Thanks to a large number of plugins developed for GStreamer, Totem is able to play all mainstream media formats, both open and proprietary ones. It also understands numerous playlist formats, including SHOUTcast, M3U, XML Shareable Playlist Format (XSPF), SMIL, Windows Media Player playlists and RealAudio playlists. Playlists are easily manageable using drag-and-drop features.


Amarok
Amarok is a free software music player for Linux or other varieties of Unix. It makes use of core components from the K Desktop Environment, but is released independently of the central KDE release cycle.

Amarok serves many functions rather than just playing music files. For example, Amarok can be used to organize a library of music into folders according to genre, artist, and album, can edit tags attached to most music formats, associate album art, attach lyrics, and automatically "score" music as it is played.

Here are the primary functions or uses for Amarok:
* Playing media files in various formats including but not limited to (depending on the setup) FLAC, Ogg, MP3, AAC, WAV, Windows Media Audio, Apple Lossless, WavPack, TTA and Musepack. Amarok does not play digital music files embedded with DRM.
* Tagging digital music files (currently FLAC, Ogg, WMA, AAC, MP3, and RealMedia).
* Associating cover art with a particular album, and retrieving the cover art from Amazon
* Creating and editing playlists, including smart and dynamic playlists. The dynamic playlists can use such information as the "score" given to a song by an Amarok script, and the playcount which is stored with the song.
* Synchronizing, retrieving, playing, or uploading music to the following digital music players: iPod, iriver iFP, Creative NOMAD, Creative ZEN, MTP, Rio Karma and USB devices with VFAT (generic MP3 players) support.
* Displaying artist information from Wikipedia and retrieving song lyrics.
* Last.fm support, including submitting played tracks (including those played on some digital music players) to Last.fm, retrieving similar artists, and playing Last.fm streams.
* Podcast


xine
xine is a multimedia playback engine for Unix-like operating systems released under the GNU General Public License. xine is built around a shared library (xine-lib) that supports different frontend player applications. Another important feature of xine is the ability to manually correct the synchronization of audio and video streams. xine uses libraries from other projects such as liba52, libmpeg2, FFmpeg, libmad, FAAD2, and Ogle. xine can also use binary Windows codecs through a wrapper, bundled as the w32codecs, for playback of some media formats that are not handled natively.


Exaile
Exaile is a music player aiming to be similar to KDE's Amarok, but for GTK+ and written in Python. It incorporates many of the cool things from Amarok (and other media players) like automatic fetching of album art, handling of large libraries, lyrics fetching, artist/album information via Wikipedia, Last.fm submission support, and optional iPod support via a plugin.

In addition, Exaile also includes a built-in SHOUTcast directory browser, tabbed playlists (so you can have more than one playlist open at a time), blacklisting of tracks (so they don't get scanned into your library), downloading of guitar tablature from fretplay.com, and submitting played tracks on your iPod to Last.fm.


KPlayer
KPlayer is a multimedia player for the KDE desktop environment. KPlayer uses MPlayer as the backend for playing multimedia files and provides a variety of additional features.

Features include:
* video, audio and subtitle playback from file, URL, DVD, Video CD, Audio CD, TV, DVB, and KIO Slaves;
* volume, contrast, brightness, hue and saturation controls;
* zooming, full screen and fixed aspect options;
* status and progress display and seeking;
* multimedia library to organize your media files and streams;
* configuration dialog;
* file properties for setting file specific options.


Kaffeine
Kaffeine is a media player for Unix-like operating systems running KDE.

By default it uses xine-lib media framework but also supports GStreamer. It also supports the use of MPlayer project's binary codecs for proprietary formats. Kaffeine developers have also produced a Mozilla plugin to start the player for streaming content over the web.

Features include streaming, DVB, DVD, Video CD and CD audio.


Audacious
Audacious is a GUI-based free software media player for POSIX systems, such as Linux.

It is a fork of Beep Media Player 0.9.7.1, which is itself a fork of XMMS. William "nenolod" Pitcock decided to fork Beep Media Player after the original development team announced that they were stopping development, in order to create a next-gen version, BMPx.

The reasons for the fork were purely technical. There were some quirks in Beep Media Player that had annoyed users, such as the ID3v2 tag handling, which had been reported as buggy by some users. The developers also had their own ideas about how a player should be designed, which they wanted to try in a production environment. Besides, Beep Media Player allegedly lacked functionalities that were considered useful for people who did streaming, such as support for an XMMS-like "songchange plugin".


XMMS2
XMMS2 (X-platform Music Multiplexing System 2) is a new generation of the XMMS audio player. It is a new design, written from scratch, separate from the XMMS codebase. While Peter Alm, one of the original authors of XMMS, was responsible for the initial design and coding of XMMS2 (late 2002 to early 2003), he has since passed on the responsibility of furthering the project to Tobias Rundström and Anders Gustafsson.


MPlayer
MPlayer is a free and open source media player distributed under the GNU General Public License. The program is available for all major operating systems, including Linux and other Unix-like systems; Microsoft Windows and Mac OS X. Versions for OS/2, AmigaOS and MorphOS are also available. The Windows versions work with some minor problems, and also in DOS using HX DOS Extender. A port for DOS using DJGPP is also available.

MPlayer supports a wide variety of media formats. In addition to its wide range of supported formats MPlayer can also save all streamed content to a file.

MPlayer is a command line application that has different optional GUIs for each of its supported operating systems. Commonly used GUIs are gmplayer (the default GUI for GNU/Linux and other Unix-like systems, and Microsoft Windows), MPlayer OS X (for Mac OS X), MPUI (for Windows) and WinMPLauncher (also for Windows). Several other GUI frontends are also available for each platform.


VLC
VLC media player is a portable multimedia player, encoder, and streamer supporting many audio and video codecs and file formats as well as DVDs, VCDs, and various streaming protocols. It is able to stream over networks and to transcode multimedia files and save them into various different formats. VLC used to stand for VideoLAN Client, but that meaning is now deprecated.

VLC uses a large number of free decoding and encoding libraries. Many of its codecs are provided by the libavcodec codec library from the FFmpeg project, but it uses mainly its own muxer and demuxers. It also gained distinction as the first player to support playback of encrypted DVDs on Linux by using the libdvdcss DVD decryption library.

Version 0.8.6, which adds support for WMV version 9 and enhances support for H.264, was released on 10 December 2006.

Free and Open Source 3D Graphics Software for Linux

Free and Open Source 3D Graphics Software: 3D computer graphics software refers to programs used to create 3D computer-generated imagery.

There are usually many stages in the "pipeline" that studios use to create 3D objects for film and games, and this article only covers some of the software used. Note that most of the 3D packages have a very plugin-oriented architecture, and high-end plugins costing tens or hundreds of thousands of dollars are typically used by studios. Larger studios commonly create vast amounts of proprietary software to run alongside these programs. But thankfully, there are always Free and Open Source software alternatives that can help produce highly commendable 3D animations like they did in the short film entitled “Elephants Dream”.

Here are some of the 3D graphics software applications that will allow those with artistic touch create beauty out of freedom:

*Blender is a free software 3D animation program. It can be used for modeling, UV unwrapping, texturing, rigging, skinning, animating, rendering, particle and other simulating, non-linear editing, compositing, and creating interactive 3D applications. Blender is available for several operating systems, including Microsoft Windows, Mac OS X, Linux, IRIX, Solaris, FreeBSD, OpenBSD with unofficial ports for SkyOS, MorphOS and Pocket PC. Blender has a robust feature set similar in scope and depth to other high-end 3D software such as Softimage|XSI, Cinema 4D, 3ds Max and Maya. These features include advanced simulation tools such as rigid body, fluid, and softbody dynamics, modifier based modeling tools, powerful character animation tools, and a node based material and compositing system and Python for embedded scripting.

Blender rendering

*Aqsis is a high quality, photorealistic, 3D rendering solution. It complies with the RenderMan® interface standard defined by Pixar.

The RenderMan® standard has been used in film and television visual effects since its introduction in 1989. Pixar has used their own implementation for their entire award winning CG features, and provided their implementation for use in the visual effects of most major blockbuster films over the last 2 decades. The Aqsis project offers a way for individuals and organistaions alike to gain experience with the RenderMan® interface without the cost of commercial software licenses.

Aqsis comprises a command line rendering tool, a tool for compiling shaders in the RSL language, a tool for preparing textures for optimal use, and various developer libraries to enable integration with third party tools.

image made using Aqsis

*Art of Illusion is a software package used for 3D modeling, texturing, ray tracing, and otherwise rendering computer generated imagery stills or animations (movies).

The goal of Art of Illusion is to provide powerful 3D modeling tools with a user interface that improves on those found in other 3D software packages. Though its interface is simple, Art of Illusion contains many features found in high-end commercial graphics software. Some of its features, like the use of online repositories and a built-in downloading tool for installing extensions, are not found in similar commercial software.

The primary creator and maintainer of the software is Peter Eastman. Peter can be contacted via the project web site.

Art of Illusion is written in the Java programming language. Distributed under the GNU General Public License, it is free software.

Art of Illusion application window

*GtkRadiant is a level design program developed by id Software and Loki Software. It is used to create maps for a number of computer games. It is maintained by id Software together with a number of volunteers.

GtkRadiant's roots lie in id Software's in-house tools. Some of the early UI design decisions influencing it could be seen in QuakeEd, the original Quake mapping tool for NextStep. Code-wise, GtkRadiant is a descendant of Q3Radiant, the Quake III Arena level design tool, which in turn is a descendant of QERadiant. QERadiant was developed by Robert Duffy using the source code for QE4, the in house Quake II level editor id Software used to build Quake II levels and is available with the Quake 2 SDK. All three are Windows-only applications. Two major things are different in GtkRadiant: it is based on the GTK+ toolkit, so it also works in Linux and Mac OS X, and it's also game engine-independent, with functionality for new games added as game packs.

GtkRadiant application window

*MeshLab, started in late 2005, is an open-source general-purpose mesh processing software program; the system is aimed to help the processing of the typical not-so-small unstructured models that arise in the pipeline of processing of the data coming form 3D scanning. MeshLab is oriented to the management and processing of single large meshes and provides a set of tools for editing, cleaning, healing, inspecting, rendering and converting this kind of meshes.
The automatic mesh cleaning filters includes removal of duplicated, unreferenced vertices, non manifold edges and null faces. Remeshing tools support high quality simplification based on quadric error measure, various kind of subdivision surfaces and a surface reconstruction algorithm from point clouds based on the ball pivoting technique. For the removal of noise, usually present in acquired surfaces, MeshLab supports various kind of smoothing filters and tools for curvature analysis and visualization.
MeshLab support also an interactive direct paint-on-mesh system that allows to interactively change color of a mesh, to define selections and to directly smooth out noise and small features.
MeshLab is available for most platforms, including Windows, Linux and Mac OS X. The system support input/output in the following formats: PLY, STL, OFF, OBJ, 3DS and COLLADA.

MeshLab application window

*OpenFX is an Open-Source, free modeling and animation studio, distributed under the GNU General Public License, created by Dr. Stuart Ferguson. He made the decision to release the source code to the public in the middle of 1999 and released a stable version a year and a half later. The product, formerly named SoftF/X, was renamed to OpenFX.
The OpenFX featureset includes a full renderer and raytracing engine, NURBS support, kinematics-based animation, morphing, and an extensive plugin API. Plugin capabilities include image post processor effects such as lens flare, fog and depth of field. Animation effects such as explosions, waves and dissolves add to the flexibility of the program. Version 2.0 also features support for modern graphics cards with hardware GPU acceleration.
OpenFX supports the Win32 platform, including Windows 95, NT, 98, ME, 2000 and XP. It can run under UNIX-based platforms by using the Wine compatibility layer.

OpenFX application window

*OGRE (Object-Oriented Graphics Rendering Engine) is a scene-oriented, flexible 3D rendering engine (as opposed to a game engine) written in C++ designed to make it easier and intuitive for developers to produce applications utilising hardware-accelerated 3D graphics. The class library abstracts the details of using the underlying system libraries like Direct3D and OpenGL and provides an interface based on world objects and other high level classes.
The engine is free software, licensed under the LGPL and has a very active community. It has been used in some commercial games. It was Sourceforge's project of the month in March 2005.

3D image made with OGRE

*Pixie is a free, photorealistic raytracing renderer for generating photorealistic images, developed by Okan Arikan in the Department of Computer Science at The University of Texas At Austin. It is RenderMan-compliant (meaning it reads conformant RIB, and supports full SL shading language shaders) and is based on the Reyes rendering architecture, but also support raytracing for hidden surface determination.
Like the proprietary BMRT, Pixie is popular with students learning the RenderMan Interface, and is a suitable replacement for it. Contributions to Pixie are facilitated by SourceForge and the internet where it can also be downloaded free of charge as source code or precompiled. It compiles for Windows (using Visual Studio 2005), Linux and on Mac OS X (using Xcode or Unix-style configure script).

image made with Pixie

Let me know if there are other great Free and Open Source 3D Graphics software applications that I failed to include in the list.

For those of you who are into creating two-dimensional models, you can check out our list of 2D animation software for Linux.

8 Best Linux Terminal Emulators You May Have Never Heard Of

8 Best Linux Terminal Emulators You May Have Never Heard Of: For some Linux users, the terminal or command line shell is a useful and powerful tool that can help accomplish tasks (from simple to complex) in a more efficient and often quicker way. Although it is not a necessity anymore, I think it would still be handy to have some basic command line skills. To those of you who are afraid to use the Linux terminal, perhaps you should get or download some Linux/UNIX command cheat sheets.

Since majority of popular Linux distributions utilizes either KDE or GNOME desktop environment, you may have only used terminal emulators such as Konsole, GNOME Terminal, and xterm. But did you know that there are capable and unique terminal emulators for Linux other than those I've mentioned?

Here is a list of some of the best Linux terminal emulators you may have never heard of (in no particular order):


Terminator
Terminator is currently my favorite Linux terminal emulator. It allows me to easily organize multiple command line sessions into resizable split panes within the same window. This way, I can do some command-line multitasking in a more efficient manner, minus the desktop clutter. Terminator is written in Python, and it will work on any modern POSIX system with Java 5 or later, which means it can also run on other operating system platforms aside from Linux such as Windows and Mac OS X.



Guake
Guake is a top-down terminal emulator for GNOME Desktop Environment that has a design inspired by consoles in computer games such as Quake and Doom. It can quickly slide down from the top of the screen using a single keystroke, and can be hidden by pressing the same key. The advantage of using Guake when compared to the standard terminal is that it is faster to open since the program is already loaded into the computer memory.



Yakuake
Yakuake (Yet Another Kuake) is a drop-down KDE terminal emulator with features almost similar to that of Guake. Its design was also inspired by consoles in computer games. Like Kate, Konqueror, and other KDE applications, Yakuake depends on Konsole for its terminal functionality.



rxvt
rxvt is a simple and lightweight terminal emulator that is aimed to be a slimmed-down replacement for the already slim xterm, removing several of its little-used features, like Tektronix 4014 emulation and toolkit-style configurability. Apart from features like those controlled by resource files, the terminal emulation of rxvt differs from xterm in a few important ways.



Tilda
Tilda is a slide-down GTK+ terminal emulator similar to that of Guake and Yakuake. The program also runs invisibly in the background allowing it to quickly slide up and down once a hotkey is pressed.



mrxvt
mrxvt is a multi-tabbed terminal emulator based on rxvt that provides DEC VT102 compatible terminals. Like rxvt, it is fast, lightweight, and flexible without depending on desktop environments such as GNOME or KDE. The main features of mrxvt include multiple tabs, dynamically changeable tab titles, customizable command for each tab, input broadcasting, fast pseudo-transparency with tinting, user supplied background images, multi-language support, Freetype font, logging, and more.



Wterm
Wterm is a fork rxvt that is also very fast and lightweight. Its look was designed for NeXTSTEP style window managers like Window Maker. It has terminal support for Latin, Chinese, and Greek characters and features customizable background images, background color tinting, and zero overhead pseudo-transparent background.



aterm
aterm is the AfterStep terminal emulator for the X Window System that is based (again) on rxvt. As described from its project webpage, aterm is designed to provide pleasing visual effects, while performing such a mundane function as terminal emulation under X.

If you know of other capable terminal emulators for Linux that I fail to include on the above list, please share them with us via comment.