Auran Jet is produced by Auran (funnily enough), an Australian games developer. You may know Auran from their first game, an RTS called Dark Reign, which did pretty well when it was released. Dark Reign was a 2D game though, and since everything is 3D these days Auran needed a new engine to power their latest projects. Thus Auran Jet was born.

Jet is the only engine I know of which is available to the general public, and which has also been used to produce a commercial game, Trainz. If you want to see Jet in action, go and grab the Trainz demo.

Although Jet is referred to as a 3D engine, in reality it is more of a 3D/Multimedia foundation. Think of Jet as being a higher level than OpenGL/DirectX, but still lower than a 3D engine. One of Jet's stated aims is not to produce an engine for one or two specific purposes, but to provide a general purpose, platform independent (eventually) environment in which to create 3D applications. While it's quite possible to create a game using Jet (just look at Trainz), bear in mind that you are expected to provide your own code for any specific aspects of your game.

If Jet could be summed up in one statement, it would be "jack of all trades and master of none". What Jet does, it does well. If you are a professional who doesn't want to be tied down to a limited set of paradigms, Jet is for you. However there is no clear path for novices or the time impaired to start from scratch and create something playable. You can't just build a level, as there is no level format. You can't just place entities and then load their position at a later date without creating your own load/save routines. I think you get the idea. Basically Jet takes what OpenGL/DirectX does, and gives you a better way to do it. It does not give you an engine to create a game in.

That being said though, there is a lot going for Jet. I think the best thing about Jet is the documentation. Documentation is probably the most boring thing for a developer to write. Who here would rather describe how a game was created as compared to actually creating a game? Not many, and as a result documentation is often ignored. Jet, however, provides the best documentation I have seen with a 3D engine. It's not complete yet, but it is being updated all the time, and even as it stands now most of the engine has been covered in some way.

Jet also provides a very complete set of examples which isolate and demonstrate a number of the engines functions. These examples, combined with the documentation, provide an excellent place to start learning the engine. This is a good thing too, because Jet is actually quite a complicated engine, offering skeletal animation, particles, LOD, a complete GUI system, networking and path finding among other things.

One of the features I would like to draw attention too is Jet's GUI system. I found this to be invaluable, as it's not common to have a GUI system this complete with other engines.

Jet's toolset is limited by Jet's unspecific nature. You get a program called JIVE, which is pretty useless unless you extend it yourself, and some Studio Max 3 and 4 mesh exporters.

Licensing is going to be a problem for some people. A non-commercial license will set you back $100 US, and if you want to sell your work you had better have a handy $30,000 US. Fortunately for those on a tight budget Auran has left RC1 as a free download, but you still can't sell any work based on RC1.

If you are looking for a place to start 3D programming, Jet is definitely a good option thanks to its documentation and examples. If you are a programming god who dreams about BSP/PVS compilers, Jet is for you thanks to its generalized nature. If you are already familiar with 3D programming concepts and just want to create a something playable, it will take you longer to realise your game with Jet than it would using a more specific engine. And if cost is an issue there are other engines that don't cost a cent.