teaching machines

Terrain Toolkit Tutorial 2: Generating Maps with Terrain Toolkit

December 2, 2012 by . Filed under fall 2012, honors 304.503, postmortems.

While L3DT is a great mapper for anyone who wants a lot of control over how their map looks, sometimes you just want a random, hilly terrain to walk around on. In this case, you can achieve your goal by using the built-in terrain generator in the Terrain Toolkit.

Make sure you have Terrain Toolkit installed, as instructed in the last tutorial, create a new terrain, and attach the TerrainToolkit script to it.

In the inspector, go to Terrain Toolkit’s create tab. Here, you will see a few different generators you can use. The Voronoi Generator creates odd-looking, pyramidal features:

The Fractal Generator creates natural-looking, rough land:

and the Perlin Generator creates, well, perlin noise:

Pick whichever generator you wish to use, and use the scales on it’s tab to define the types of features you want it to generate (these scales vary between the three generators, try a few different settings to see what gives you the terrain you want).

The last two tabs in the create window are the smooth and normalize windows. The smooth window can be used to remove the fractal look from your terrain:

(all examples from now on will use the perlin heightmap from the last screenshot)

And the normalize window can be used to scale down and blend the terrain together:

You can use one of the noise generators, as well as both the smooth and normalize tools on one terrain. Unfortunately, you cannot use two noise generators for the same terrain.

The next section of the terrain generator is the erode window. Any number of erosion tools can be used on the same terrain, and each produce a slightly different effect. Thermal erosion acts on the entire heightmap, smoothing jagged areas and adding texture to smooth slopes:

Hydraulic erosion simulates rainfall effects to give a weathered look:

Tidal erosion also simulates water erosion, but only over a small vertical area, where tides would be.

Wind erosion also simulates weathering, but will give a very jagged look on noisy terrains:

You can combine these tools any way you like to get very different terrain looks. For example, if you want a strange, jagged terrain, you can use the Voronoi generator, and thermal and wind erosion to get this type of terrain:

and you can use the fractal generator, smoothing, and hydraulic erosion to get a hilly effect:

Add some texturing, water, and lighting, and you’re good to go.

Have fun!