I created a super small test project with a single grass mesh on a landscape in order to reproduce the grasstypes/raytracing issue.
Open the project in 4.25:
Great performance, and notice that the Grass has no raytraced shadows (someone must have realized it was stupidly expensive)
4.26:
massive performance drop, Raytracing is enabled on all grass meshes by default and even seems to ignore any culling distance values I enter into the grasstypes files. You can even visualize the problem perfectly by going into the grass type and turning cull distance down.
This is with Cull distance at 2000, the red line is the Real Cull distance… but raytracing completely ignores it and renders shadows for grass that isn’t even visible.
Same exact project, only change is opening in a different engine version.
This test project is 3MB and can be downloaded here:
https://www.dropbox.com/s/l0jqbscivg…ng425.zip?dl=0
To reproduce you can right click the Uproject file and choose Switch Unreal Engine version and that should be it.
This wouldn’t be such a terrible issue, but there doesn’t seem to be any way to disable raytracing specifically on the grass. There are not options for this in either the static mesh editor or the grass types file. There is also no Grasstypes specific CVAR.
Cheers
Joe