I have some ivy which has the WPO and wind grass shader, and the shadows look so choppy and strange, i cannot figure out how to fix this issue.
Please help!
raytraced shadows do not have wpo compatibility. the bvh is static. so you trace a moving object against static shadow mesh data. leads to inaccurate shadow depth testing and this kinda wobbly rng shadow.
Even in the latest versions ? We still can’t use raytrace shadows with vegetation ? Are there some workarounds ? Some cvars ?
use the classic shadow map cascade. or vsm. that is for directional lighting. the latter seems to have improved the memory footprint. so… you should need raytraced shadows only for very specific shadow scenarios (like overcast lighting. still gotta deal with shadow flicker in that case tho. or find alternative ways to move the foliage and update the bvh. like skeletal mesh trees and procedural animation. this is a lil expensive, tho. : )
for regular instanced static meshes you should have the…
r.RayTracing.Geometry.InstancedStaticMeshes.EvaluateWPO 1
…cvar. it does not work for explicitly painted foliage, tho. i don’t have a test case for this and hism right now. sry.
I wanted to build a special plugin for this case, a plugin using as a base the VSM, but I was relieved to find out I don’t have to anymore because with some quick tests it seemed raytraced shadows could achieve a result similar to this. Soft shadows are not just for overcast, as you can see here we have a sunny day - so directional light, but also very soft and also sharp shadows in the same scene. As far as I know you can not achieve this with the shadow maps included in unreal.
RT shadows could, but since they are trees, they would need to be animated.
