SpeedTree: Wind + Tesselation + Instancing = SM5 Error?

Hello everyone,

This is my very first question, so please forgive me if I do something wrong. I have searched before posting and did not find anything similar so far. I have bought SpeedTree the day before and have to say it is amazing, but I have come across one problem that I could not get rid of so far.

It seems like when using the “SpeedTree” node for wind and LOD transition plus tesselation together on instanced meshes, the material breaks. I would like to have my trees being paintable as instanced foliage, where the LOD0 is using tesselation on some areas of the trunk to higher the detail when viewed close range. However, this results in the following compiler errors:


Error [SM5] FlatTessellation.usf(129,2-33): warning X3554: unknown attribute partitioning, or attribute invalid for this statement, valid attributes are: domain

Error [SM5] FlatTessellation.usf(129,34-64): warning X3554: unknown attribute outputtopology, or attribute invalid for this statement, valid attributes are: domain

Error [SM5] DebugviewModeVertexShader.usf(68,26-56): error X3504: array index out of bounds


Here is a simplified material where I have removed everything that is not needed:

http://puu.sh/sXHyu/23e6cca627.png

As soon as I remove the SpeedTree node or take away the tesselation and/or displacement, the material compiles. Well, there is not much left then anyways :slight_smile:

One important thing to mention here is that the exact same material works on static mesh actors. However, as soon as “Use with instanced static meshes” is ticked, it errors out.

Could it be that the VertexNormalWS somehow collides with the SpeedTree node, which is responsible for vertex transformation? Did anyone encounter a similar problem?

Thank you very much for your help!

Yep, got the same problem. I think you can not have tesselation and ST on foliage at once. Don`t know if that was the case before because I am using it for a couple of weeks now.