Speedtrees re-compiles shaders every load

Assets imported from Speedtree seem to require re-compiling every time the UE editor is launched. This means that I’m sitting watching 5000+ shaders compile for over an hour. Any idea what’s going on here? Can I resolve this from my end, or is it a bug?

In addition the auto-save feature kicks in every so often. I like auto-save, but I don’t like how it wants to wait for the shaders to finish compiling. That means I get about 15 minutes of editing time then up to an hour of a frozen editor. If the editor isn’t actually going to preserve the compiled shaders between reloads, can we please not lock up the editor during saving? At the very least, can the UI not lock up so there’s some kind of indication of progress? For example, my editor has frozen on “Compiling Shaders (3,660)” for about 30 minutes, because of the save attempt. I know it’s made progress but I have no idea how long it has to go.

I suppose while I’m at it I’ll mention that this process seems slow. The tutorial videos I’ve watched seem to compile much faster. I’m running on an Intel i5-3450 quad core CPU with 16GB of ram. Surely it should run better than it does.

Edit: additional comments. Once my shaders finished compiling, I packaged my game and shut down the editor. The packaged game shows half the tree instances as grey placeholders. When I reloaded the editor, the exact same trees had lost their compiled shaders. Then without any interaction all the tree instances dumped their compiled shaders and started compiling all over again. I’m pretty sure this is a bug.

I have the same problem. My own made grass in the speedtree modeler does not need to compile shader every time and it work perfectly in a standalone build but the broadleaf tree, which comes as an example, has to compile on every start of the editor. This tree also has the grey placeholder material in an standalone build.

I have a hunch that if you do “re-import asset” from the mesh window this problem starts occurring. I re-imported my trees from scratch into new folders and the fully new imports don’t have a problem with constant re-compiling. Give it a try and let me know how you go.

By the way, how did you do the grass? Mind showing a coupld of screenshots of how you used it in UE and how it’s set up in Speedtree? :slight_smile:

That looks nice. I found some serious slowdown with a lot of bushes too, spacing your objects correctly so there’s no unnecessary overlap in UE is really worth the time and effort. Then you know you’re using them efficiently.

I made it with this tutorials:
part1: How to make Speedtree grass in UDK Part01 - YouTube
part2: How to make Speedtree grass into UDK Part02 - YouTube

It looked good but the performance was realy bad. Make sure you keep the polycount down.

I updated to the modeler version 7.07 and I also downloaded a newer verion of the assets. It works now properly.