How to make landscapes with lush, low lag vegetation

Vegetation is always a problem in Second Life and on opensim. Either we don't have nearly enough of it or we have sims so laggy you can barely move. Many people will tell you that can't be avoided but they are wrong! All you have to do is use the right kind of plants in the right place. Here are some tips. This page is under constant update so there's more to come!


Three overlapping sculpt grass fields, two groups of 87 spruces and two small groups of bushes in the background and a single bush up front, that's all. Even with the sculpt fields there's hardly any lag and it looks so good you can almost believe it's Real Life. This was supposed to be a promo picture for the bush up front but everything blend together so well we can't really highlight that particular plant. So let's jsut use it as an example how good even out fairly low poly plants can work when used intelligently. (Click on the image for a full size view.)

1. Think layers!

2. Consider the whole picture!

3. Fill up with big groups!

One of our specialities is large groups with multiple plants - anything from two to more than a thousand. These save a lot of both land impact/prims and lag compared to individual plants so the more you can fill up with them, the better.

4. Reuse assets!

5. Avoid alpha blending!

Good plants will always have some transparent bits since we can't model each and every leaf and petal as mesh - not if we want low lag anyway. But there are two kinds of texture transparency:

Alpha masking: Each pixel in the texture is either fully transparent or fully opaque, nothing in between.
Alpha blending: Pixels can be semi transparent.

Alpha masking is much, much easier for your computer to render and it also avoids the infamous "alpha bleeding" you so often see. Unfortunately we can't always use aplha masking, it can give a rather "blocky" look, the shadows can be very harsh under some windlight settings and some plant textures have details so fine they just can't be presented properly without soft transitions between the transparent and non-transparent parts.

That means we sometimes have to resort to alpha blending but try your best to avoid it. You coputer (and your visitors') will thank you for it.

Most OPQ plants use alpha masking as default but since they are modifiable, it is possible to switch to blending if you need to.

OPQ - Quality content for Second Life and other virtual worlds

Thursday, 24 September 2020