Friday, July 27, 2007

Sculpting MMO Landscapes

Techniques of Sculpting MMO Landscapes

Firstly let’s start off with looking at how MMO landscapes are presented within the world of massive multiplayer online games.

Many developers when creating a zone/persistent based MMO use a variety of tools. Using the zoning based method can save a lot of loading time and allow the developer to pack a bit more detail on the poly count rather then on a persistent terrain were a lot needs to be carefully done to prevent lag. Although using persistent based method can give the player sense of depth and freedom with the MMO.

The actual terrain with any MMO game is usually made within a modelling package such as Maya, 3ds max or Z-brush. However some developers prefer to use there own In-house world editors which can be an advantage and disadvantage.

Using a modelling package can give its advantages and disadvantages, advantages are you have complete control on how the terrain is shaped, the detail of the terrain and easy modification to the terrain. As well as being able to cut holes in the terrain to allow caves and tunnels to be placed. However disadvantages of this are using a modelling package can sometimes give you a very high poly mesh. Advantages of using a world editor is that the mesh presented for the terrain is ready for in game use. All you have to do is add some elevation to the mesh and hit build. Disadvantages are that the editor’s mesh is limited on the amount of polygons, so you couldn’t add extra detail on cliff sides or huge crevices in the ground. However there’s a way around both methods. Combine them.

Combining both methods seems to give of a greater benefit for the developer and can produce excellent in-game results. The technique myself uses a-lot, is to create your terrain in your preferred package, I use Z-Brush 3. Then export the terrain to World Machine, World machine is a complex world generator which can produce highly detailed height maps which is perfect for MMO landscapes. Once world machine has done its work and the height map is produced, you can then use the in-house world editor to create the detailed terrain by using the editor’s in-game ready mesh. Some editors even allow the developer to create bigger meshes to add more polygons for this technique.

Once you’re happy with the mesh poly-count, apply the height map that is generated from world machine to the mesh in the editor. With luck you should see a highly detailed landscape but with a low poly count.

Just a little note, world machine was just an example program I use. There are others out there. Terragen, Geoscape and L3DT are all excellent programs which can produce some excellent height maps for your landscapes.

No comments: