Performance cost is really high, and the sad thing is that when using LODs sss tends to look different as the geometry gets simplified, for that reason i made the shader that fades sss strength with distance so when viewing LOD2/LOD3 there is almost no sss, so far it does descent job.
I’m kinda amazed people like the work so far. Pretty much all the people on this forum seem to be working on something pretty incredible and nooby old me is stuck trying to figure out how trees work.
Happy New years everyone! Here’s to an amazing year!
@RayJones: You are a genius sir. I did not know those were a thing in Unreal, will get right on it. That’s perfect for a lot of the background trees.
@Piroman: If it’s not too much to ask, can I see the part of the shader where the sss fades out? I can’t figure out how to do that properly and it’s an issue.
I wasn’t able to get much done over the Chrissy break for obvious reasons, but here’s little screenies from some of the fixing I did on one of the leafy tree models, not too much of a change in polycount, but a very significant change in structure, and some more control points added to the master material. Also worked on the lighting and fixed up some broken settings with the dynamic GI, and I really, really, love the wind riffling through the leaves on these trees. MMMMMmmmmm. Gonna have to fix those branches, look at those hard edges. Ouch.
Bravo!
Great work!
My game shall have the day and cycle too, may I ask how did you integrate it? Via blueprints? I am going to switch to dynamic GI as soon as possible. Did you use this tutorial? https://wiki.unrealengine.com/Light_Propagation_Volumes_GI
Cheers! 
That’s no problem at all! Always happy to help. 
The day night cycle is done in blueprint with a few custom classes done by the coder I believe, to differentiate time. However I think the basic level layout already has a distinction between day night as it can transition between starry and night time stuff. We just hitched it up a bit more to the dynamic lighting system so it worked properly.
That tutorial will give you the answers, and so will the UE4 core documentation:
This tutorial here should give you some pointers on day/night stuff to start with:
Eventually you’ll want to call different parts of the level to change over time, for instance changing the fog volume values, atmospheric scattering and light colour over time will help give you a much prettier effect as the core UE4 atmospherics shader is very basic. It does the job, but you’ll need to work to make it really spectacular.
For the most part though, most of our day/night and weather stuff will be directly in blueprints as it’s easier to implement and also involves a lot of particle and modular changes at runtime, which are easier to test without having to rewrite code all the time.
Are these SpeedTree trees?
They are indeed made with SpeedTree. Despite being terribly unstable and having some annoying limitations, it’s still one of the simpler ways to handle things as complex as a tree efficiently.
What kind of instability issues are you experiencing? I have had fewer crashes than I can count on one hand while using Speedtree for months, which lead me to believe there might be some issue with your installation, rather than the software itself. It might be fixable.
I can guarantee a crash at least once or twice a session. The fastest way of course being to hit randomise too many times in a row, which seems to produce a fairly straightforward ‘too much happening at once! Hrk~’ crash.
Then there’s the random 3D space rotation crashes. Crashes on save are pretty regular, I switched off autosave for this reason. It seems to happen more frequently once the leaf cards have textures, tested with high texture resolution and low texture resolution, seems to be no difference. Same with polycount. The program can handle million polys and low polys. Though higher polycounts seem to lead to crashes more regularly. Using spruce branches on a standard trunk seems to cause more regular crashes, as do broadleaf structures, even after cutting down. I’ve tried reinstalling, no dice. At this point, given that the the company hasn’t updated in a while, I’ve decided to just push through till we’re done with it. I reported the issues, and gave some useability suggestions, but there’s really not much that can be done without a way to easily replicate the bugs. Using the leaf culling calculation can also cause a crash.
That rough man. I’m guessing you’ve tried the latest v7.0.7 version? I had some issued before with v7.0.6 (I think) that froze about 50% of the time when I saved and a few other crashes, but haven’t had any issues what so ever in v7.0.7.
Not that I think it’d make a big difference, but what OS (and version of it) are you using? How much RAM do you have? Did you try simply starting it as administrator?
It should be fixable, since I’m not experiencing any issues but it’s hard to pin point without much information. : )
Yeah, I’m using 7.07, that was the first thing I checked. I haven’t tried starting as admin, though mostly because that’s a pain to do every time. Information wise, I can’t help much either, coz even though I’m very well versed in troubleshooting, this is a straight up CTD without a message. Speedtree either hangs infinitely or just quits. I’m using win7 ultimate, 12gigs of RAM, GTX 580, core i7 980X, it’s installed onto an SSD. So performance shouldn’t be the issue. Don’t worry about it. I’m kinda an old generation 3D artist, so I’m used to working with instability. 
Starting it as admin probably won’t help but if it does you can set Speedtree to always start as admin: Configure Applications to Always Run as an Administrator | Microsoft Learn
I used Win 7 back when I had issues with Speedtree but I’m pretty sure those were resolved by 7.07 and not by switching to win 8.1 which I did around the same time.
I agree that your hardware shouldn’t be the problem, it ran fine for me on 12gb RAM, Radeon 7970 and i7 930 earlier this year before I upgraded.
Years of unstable softwares have given me Ctrl + S Tourettes, my left hand does it every few minutes or before any major task automatically.
Hello,
You can always report problems with the SpeedTree Modeler to the SpeedTree or to our support address. We’ll try to get to the bottom of it.
I noticed that you did your own wind in your material instead of using the SpeedTree node. Could I ask what you didn’t like about SpeedTree wind?
@Sitrec: I’ll give it a go. We’ll see what happens. Ahhhh man, the incremental save folder. It sure fills up!
P.S. Switch to Windows 10 alpha. It’s Windows 8.1 Fixed. But still offers no compelling reason to upgrade from win 7. **** you metroooooo. Shakes fist
Already reported about five months ago I think. Everyone was very nice and hemmed and hawwed but without an log files and a completely random trigger, even example files provided little help.
I actually really like the wind! Only problem is that it creates issues with the LOD’s. The simple wind shader is there to give me some control in unreal, but also acted as a safeguard for when the speedtree wind broke. And when I say broke, I mean models disappear and flicker in and out of existence. I identified LOD’s as the culprit after a lot of trial and error. The current trees have better LOD’s and are more efficiently setup so I’m hoping my latest changes won’t break everything as I’ve added wind to the game and the master materials now can blend between storm settings and calm gusty settings. So far it’s working though.
Sorry to bring this corpse back to life, but how many tris do you use per tree? I model mine manually using reference images, but it is hard to get a decent polycount at times and now that I am extra careful by trying to stay at around 1-2k tris without leaves, I have a feeling that they look edgy and stuff.
Thanks
I’ve done a lot of work on optimisation since this thread started so I do actually have an answer for that. As a general rule, if you have a lot of trees on screen, you want to keep each tree under 8k tris including leaves, you’ll start getting larger and larger drops in performance after that point. I LOD hard at the moment because the tree density masks the ones in the distance.
Fortunately for you, your trees probably don’t have to be massive and climbeable, so you can take shortcuts with rendering, like replacing entire branches with a single plane and using normals to trick the lighting. Generally speaking, so long as you stay under the 8k mark, you should be fine for increasing the branch polycount. Also use and test the adaptive polys per branch, depending on how much we’ll see it, for instance, extra tris for main branches would be fine, but low tries for the trunk (which sees little benefit from higher polycounts, being mostly round and straight) and twigs. Can I see some of your trees, I’d have a better idea of where to point you.
My material won’t show up texures, Unless I hook up albedo texture directly to Base Color output. But then all of the subsurface scattering is gone.
I don’t know if this will work sharing a material this way, but here is the link. For some reason it’s not texured. As in the leaves on the tree are only green. The material itself works as intended, (subsurface scattering looks really good), but it’s only green, no texture.
This is my result. The trees have no texture.. But If I connect the Albedo alpha masked texure to the Base color output, All of my subsurface scattering on the leaves material is lost.
Could I get my hands on the material? I re-created it in unreal engine 4 but it won’t work