Landscape is disappearing on 4.15

This landscape worked in 4.14, but disappears a couple of frames after loading on 4.15 (I think 4.16 also).

Getting a warning about shaders that I think is new, not sure if it’s related:

LogMaterial:Warning: Update reflection captures only works with an active feature level of SM4 or greater.
2017-05-05 15:42:36.234561-0700 MM_04[13601:1145429] [2017.05.05-22.42.36:234][ 51]LogMaterial:Warning: Update reflection captures only works with an active feature level of SM4 or greater.

I dropped the landscape material down to the something very simple and have verified that other objects render when it is applied.

Perhaps some of the recent shader optimizations might cause issues if set incorrectly? Not sure what else to look at.

Working on a sample project to try and demo the problem.

TestProject

I’ve found that the problem happens when you stream in the level on the iPhone. Tested against 4.15.2.

The test project delays load 5 seconds then loads the landscape. I see the attached spline road, but not the landscape mesh.

If the project is packaged with the main level being that containing the landscape it shows up as expected. Also it shows as expected on PC and MAC builds.

Interesting that it streams in, then disappears. As if on iOS there’s a visibility toggle that is happening on load completion.

Also I tested and it works as expected on a packaged build on Mac.

Not sure what I can do beyond removing landscapes. Any idea if this is a known bug or not (this wasn’t a problem in 4.14) and if so if there’s a fix on the horizon? Perhaps that fix is in 16 preview 3…

Hey theonecalledtom,

So I found a bug entered for Landscapes failing to render on mobile devices when used in conjunction with lighting scenarios. Based on your description, it sounds like it is only occurring on mobile and when you toggle the visiblity of a level or dealing with level loading, which is most likely related to the same issue due to how we handle Map build data and level streaming now.

UE-45015

It is set to be fixed for 4.17, but that is not always set in stone. Thank you for taking the time to investigate and report this issue.

H.

Hi Andrew - thanks for looking at this.

It’s difficult to tell from the bug if it is the same thing from the bug description. In my test case the landscape works on mobile unless streamed in.

Might be worth adding that to the bug.

4.17 might be too late for me - I got the feeling that non-metal iOS devices are going to be dropped on this release and need to look at the device market penetration before making a decision on whether to follow this at this time.