I’m working on some very large douglas fir trees, and using the Nanite Assembly Pipeline. I’ve written an exporter that takes my trees from Blender into UE, with full instancing etc.
I am seeing that when the camera is close to the bottom or top of the tree, the tree will appear/disappear from view. Anyone know a fix for this? (Using Voxelization for shape preservation)
Hello there @mattyinthesun!
From your footage, considering the way foliage dissapears is tied to angle and distance, it looks like Nanite is culling the tree. So, the first test that comes to mind, is to ensure your foliage is set to preserve it’s area.
To check that, open your mesh in the Editor, go to the Details Panel and look for Nanite Settings. There, check the “Preserve Area” box, hit apply below, then save the changes. This will force Nanite to maintain the surface of the original mesh visible at all times. A practical example of the change can be seen here:
Alternatively, if the issue still happens even, it’s possible that the tree’s bounding box is falling short, and when the camera moves, UE stops rendering it. To adjust that, select your tree, go to the Details Panel again, and look for “Bounds Scale”. Test by smal increases, from 1 to 1.2, and so forth. This will ensure the tree remains “in frame”, and stop it from being culled.
I actually solved this - This tree didn’t have correct bone assignments on the trunk/branches - the skeleton was there, but the trunk/branches weren’t bound to it. Once I fixed that, the flickering went away.