So as of 5/11/10, Aquaria, Gish, Lugaru HD, and Penumbra Overture pledge to go open source
Note, that this doesn't mean the art and other assets are free, but the source code powering the engines is. (So you have even less of a need to write your own now
Penumbra Overture's engine is now free and has some nifty features (taken from Frictional Games' announcement
* Physics sound system. This is all the code that is used to play and tweak the sounds heard during physics interactions (bumping, sliding, etc). A lot of work has gone into the system and is the result of a combined effort between me and Jens (who does all sounds) for several years.
* Stencil shadow volumes. The shadow system in the engine is quite robust and can work on pretty much any mesh, something that shadow volumes usually don't. It is far from state of the art these days (when shadow maps rules), but should provide nice info for the curious.
* Serialize Class system. This is code used to easily save and load classes to disk. It is very useful when creating a save system for games.
The engine contains tons of more stuff (almost 100k lines of code), but these are the most interesting stuff I could think of right now. I am sure there is more for awaiting to those brave enough to explore its dark depths!
Finally, it is also worth noting that this is the latest and final version of the HPL1 engine. It is the beast that powers all games of the Penumbra series.
OALWrapper: This library is made almost entirely by our tool programmer Luis, who actually started out doing work for us on the OpenAL sound implementation. This library is simple and easy way of accessing the OpenAL functionality and was made since there is a strange lack of free sound libraries. This is also the only part of the open source release that we will continue to update and we hope that others will find it useful and contribute themselves!
Pretty cool. Can't wait to see what the other game's engines will feature and support.
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