Recently I have opted into the Unity 5 beta and have started playing around with some of its features, one of them being SpeedTree. Don’t get me wrong, the trees look great, except the draw call count is through the roof. I’m using unity’s terrain engine for tree placement and when I make a dense forest of maybe 5000 trees my draw call count is way higher than before it was with basic tree engine trees. I’m seeing about 6-7k draw calls with a forest this density as opposed to about 500 with basic unity trees. If you have any advice or help that would be greatly appreciated! Thanks for your time.
I spent some time testing this tonight with Terrain Trees. Like others have reported too, vert/draw call shoots up, FPS tanks. There seem to be a few factors with these Speed Tree trees and Unity, not sure who has the ball: Terrain settings like Max Mesh (force billboard), Tree Distance (cull), and Billboard distance do nothing.
I set up a pure flat 128x128 terrain, put an FPS in a corner looking inward, mass placed 250 trees, 5.6Million tris.
Now depending on your requirements and use-cases, you can bring this down by forcing lower LOD. I created a prefab from the Broadleaf, removed 11 of the 12 colliders, removed LOD 0 and 1, set the Renderer for those in LOD slider to use LOD2, pushed up the Billboard and Cull % in slider.
Repainted that new prefab on terrrain 250 and down to a little over one million. There are obviously trade-offs in the quality, tree “Snap” visibility as LOD shifts to Billboard but at least I have a very dense wooded area again (and culling works). You might find an acceptable tree v performance point without resorting to removing LOD 0 and 1 by just shifting around those LOD sliders.
By comparison, same test with the older “Alder” tree that used to be part of Unity standard Assets, 250 mass placed with Terrain settings working - 168k Tris.
EDIT: There is no Slider in the typical sense (sorry); in the Tree Panel showing the % of the LOD breakouts, you can click and slide the borders and slide them around.
SpeedTree currently has some issues. One of them is batching, you have to disable SmoothLOD on your trees so batching works fine. This should reduce your drawcalls by a significant amount.
twobob
4
1000 draw calls for these trees at distance…
I did note that a WIND ZONE can prevent batching it would seem
