I have a question on (volumetric) lighting and light bleeding through landscape/heightmesh.
In the following pic, the directional-light that is used as the Sun in Ultra Dynamic Sky (I’ve tested with a regular light as well, pic after), shadows the world, grass, etc, but the heightmesh I am using doesn’t seem to be properly casting a shadow… I might have missed something but modified-settings I’ve played with shown:
Unreal 5.3, using Lumen in these screenshots, but tried with no global-GI. Using Virtual Shadow maps as well as nanite for the foliage. Not much else in the world as you can see. Mesh/material are both set to two-sided.
Unsure if I have to enable static lighting somehow, or another setting. I feel a bit stupid/stumped I’m stuck on this; what good is an open-world if I break it in such a way as to break-realism??
Alas, as it-itself is derived from a Runtime Virtual Texture, it cannot itself have such characteristics; there is no section to have the heightmesh render to a virtual texture, hence no such setting…
The landscape itself is set not to render, cast shadows as you generally don’t see it (vis-a-vis the heightfield mesh). Otherwise, turning it on seems to yield no relief. It does have those settings, but alas…
Onto something with Hidden shadow, but a ton of artifacts, playing around…
If the landscape is set to show, it will be this ugly-double-thing where it shows through. Since one has height,normal-information, and mesh-deformation lighting typically comes-through in the height-field mesh, but global GI seems an issue.
Letting the landscape show through somehow seems a path to relief, but again, artifacts:
I feel dumb only having noticed this once I started mucking with foliage…
So i never thought Nanite on the landscape would do much since it’s effectively-hidden behind the RVT; I always looked at it as a glorified render-target which it is.
However, since Nanite renders into the virtual shadow-maps automagically, I thought I might help. SEEMS to, so far, but still muking, there’s odd stuff at a distance, but looks good up close.
Not Resolved! The far shadows were caused by the LODing of the virtual heightfield mesh. This caused it to LOD below/behind the landscape, so it was leaking through.
The workaround is to increase the LOD Distribution value such that the distance heightfield mesh has enough tessellation to still ‘stretch’ over the landscape.
In fact, I turned off ‘Cast Shadow’ on the heightfield mesh entirely…
Also note that the issue only presents as resolved in the play in a standalone session (which y’all should be doing anyways…). In the editor it’s all FUBAR…
I think the bug is the heightfield mesh just doesn’t seem to show a shadow. I’ll have to throw a sample project together, but it’s only got normal-lighting.
Yeah, so the hidden-in-game on the landscape kills the grass (duh!) and whilst you can squeeze a shadow out of it all, suboptimal, and the heightfield mesh just doesn’t seem to cast any kind of shadow, lumen or otherwise.
I’ll test, but I’m going to actually call this one a bug. The mesh is clearly given the option to cast shadows, etc but nothing one toggles makes any visual difference.
