Larry Niven´s Ringworld for Celestia

This is a Celestia Add-On scenario that lets the user visit and examine the Ringworld in full 3-D (all images on this site are actual screenshots from the scenario).

Celestia itself is a free, open-source space simulator available for both Windows and OS X as well as for Linux. See the Downloads page for details.

The source files are also freely available (see the Cookbook) to make it easier for other Add-On artists to modify or enhance the scenario to their liking.

Disclaimer: Larry Niven´s book has inspired this work, but Mr. Niven is not responsible for anything in the scenario. Any problems, errors, bugs or other issues is not in any way connected to him.


I read Larry Niven´s Ringworld more than twenty-five years ago, and can´t honestly say i remember much of the story. But i do remember the scenery... It is probably the most iconic of all sci-fi megastructures: an artificial habitat that completely encircles its star - with a surface area about three million times that of the Earth.

In the book, a small group of explorers - both alien and human - arrives at the Ringworld, and proceeds to explore a small part of it - along the way discovering the ruined cities of a fallen civilisation that supposedly built the Ring several million years earlier (we later learn this isn´t exactly so, but that is a different story).

What stands out from all this is the Ring itself. It was a truly enigmatic, magnificent structure, and Niven managed somehow to paint it so vividly the imagery still sticks after so many years. Of course, something like that will never be built - anyone with the resources to do it will most surely come up with better ideas for living space. But that does not change the beauty of it at all.

So, here it is for Celestia. I have limited the scenario to a few key scenes from the first book, to keep it light enough to be within the rendering abilities of most modern computers. One can visit the Ring from all angles, dive beneath the clouds and see the Great Oval Ocean, the Fist-Of-God mountain and the Maps of Known Space. Or lock on to the Lying Bastard for a flight through the star system, or to any of the four protagonists for a trip through the RIngworld´s skies...

Note that your will find both a High-resolution and a Low-Resolution version on the Downloads page. The Lo-Res version is limited to just a couple of locations, the models are simplified, and all texture-mapping is scaled down considerably, as it is optimized for a low-end computer system.


- Runar Thorvaldsen (rthorvald), jan. 21, 2009.

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