GPU trees optimization

You have probably noticed that the video I make can be quite slow. It is because with Unity trees, I get 10 FPS on my I7 / Nvidia 950M laptop. I have a very good procedural Jungle, but Unity show its limits. Who is going to play a game that is running at 5 FPS?

Another problem is the low quality of the billboard from the Unity trees system, reminiscent to the 8 bit times it seems. They are using a single atlas for all the trees, but the texture is very small (512×512 ?) so the result with 20 Unity Trees at the screen is totally awful.

Seriously Unity, how can you continue in 2017 to sell that technology?

What choice do I have now?

1) do not use Unity Tree. Then why using Unity in the first place? SpeedTree are flawed too, with their 10,000 poly per desktop tree quality!
2) Use less type of trees, and have a game made with a couple trees that will look like what Unity’s game are looking => crap.
3) Do a proper optimization and get the things to run like Ubisoft can run a game with their engine, that mean fast.

I choose 3. And you know that the more billboard you display, the more speed you have. So the quality of the billboards have to be top notch in order to not be visible. They need to catch shadow, to support Global Illumination, and show up only where the camera is looking and if they use an anti-aliasing shader that will be perfect.

Introducing Alt Tree. assetstore.unity3d.com/en/#!/content/76657

This cheap asset is the kind of product that is not looking exciting. No fancy advertising, the author is not good in English.
It took me 3 days to be really be comfortable with it, after fixing some bugs I have to say, but the Author has been really motivated and upgraded right away.

Alt Tree is a solid product, stable that I use all the time now, without a crash. It supports everything, meshes, SpeedTrees, Unity Trees… and uses its own shaders, that are super fast, powerful (the wind is top notch) and supports GPU Instancing.

What you see in this picture is now  running at 35 FPS in ‘fantastic’ quality with full post effect pushed at the max. With lower quality it runs at 50 FPS. Before, it was running at 5-10 FPS.

These are without Post Effect and with a higher distance, up to 8000 trees on the screen max distance on grass, shadows on billboards: 25 FPS average on my $800 Laptop.

This asset is a game changer. No one will buy a game that is too slow, with Unity only, you can give up your project or better work on a “ball falling game”. If Alt Tree was not existing, I would have to write something similar myself. So this time the Asset Store saved me a lot of time and this asset is really not expensive: thanks to the author !

Now I have plenty of power to add characters, particles, buildings!

Some notes for the ones who are starting with Alt tree.

1) read the doc and use the tool to import all the Wind first. This way you will not have to manually assign the wind to each of your trees, it will be done automatically.
2) drag and drop World Creator terrain in the Alt Tree Import Terrain Slot. Do not touch the basic options.
3) import!

You will have to import all your trees one by one, but you only need to do it one time.
Next time, Alt Tree will see that you have already imported your trees, and will only place the trees using the Alt Tree corresponding trees, it takes 1 min to re-import trees.

Now you are running with +300% speed increase.

Author TheWolf
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