Landscape LOD

What is landscape LOD? LOD is an abbreviation of Level Of Detail. This is a really cool performance trick. What does it do? Well, imagine having a scene with a lot of detailed objects. It’ll probably render slow, because it’ll have to always render everything that’s visible. But why would you care if there’s just a really small bump on a stone that’s like 100 or 200 meters away from you, you won’t be able to see it anyway. What if you could tell the engine that if an object is a certain distance away, it can make the object have less polygons, so it’ll render faster? That’s where LOD comes into play. It’ll give our landscape less polygons in the distance.

What do we need?

- We need nothing more than the objects we used in the previous tutorial.

How do we set this up?

- Landscape LOD is easy to set up:

The first parameter states if the LOD is on or off (true being on).
Second parameter is the distance at which the objects should have a low poly count.
Third parameter defines the minimum precision of the landscape.
Fourth parameter is the distance at which the objects should start getting a lower poly count (just reduced a little bit).
The last parameter defines if the altitude could be discarded when removing the polygons.

- To notice the difference, we’ll need two more things:
We want to have a high precision for our landscape at first, so there’s more difference.
We can’t see polygons when rendering, so we need to tell the engine we just want to see wire frame images. We do this by calling:

How do we render it?

- It’s exactly the same as the previous example.

Things you can add/change yourself

- You can try fiddling with the precision of the landscape. Bear in mind that the LOD works per chunk, not per polygon, so you can’t make the landscape go from ultra quality to ultra low quality smoothly.