Overgrowth takes place in the savage world of Lugaru where rabbits, wolves and other animals are forced to use paws, claws and medieval weaponry to engage each other in battle. Combining 3rd person adventure platforming with intricate melee combat, Overgrowth achieves a unique feel. Overgrowth also benefits from Wolfire's brand new Phoenix Engine which has been built from the ground up to allow the use of cutting edge graphics, animation, and physics. Add to these exciting features Overgrowth’s realistic artificial intelligence and streamlined control system and the result is an astoundingly immersive experience.
We recently dramatically improved our terrain detail while optimizing the game at the same time. Here's how it works!
Posted by jeffr on Jun 3rd, 2009
OffTheGrid is a terrain technology we developed to bring detailed terrain data to in-game resolution without losing much detail. Below you can see a comparison between heightmap terrain (left), and OTG terrain (right). The OTG terrain is actually using fewer polygons.
We start with a high-polygon terrain, and iteratively discard the least important polygon edge (as defined by Dr. Michael Garland's quadric-based polygonal surface simplification algorithm) until we get down to our in-game polygon count target. We then apply the normals and color map from our high-polygon terrain onto our simplified mesh. Here is a wireframe image showing how OTG terrain uses less polygons by choosing them more carefully.
With traditional heightmap terrain, it is only possible to accurately represent soft, rolling hills - small details like rivers, sand dunes, and cliff faces are all smoothed away by the grid. Using OffTheGrid terrain will allow us to portray a much wider variety of environments than we could with heightmap terrain. Here is an example of a small mountain detail that is destroyed by the grid (left). Please keep in mind this is just our base terrain mesh -- we are going to add vegetation, detail maps, and other environmental detail on top of this.
Now that we have an effective technique to create an efficient base mesh, do you have any other ideas for how we can improve our terrain? I have a few ideas, but I'm not sure which is the most important.(permalink)