Unreal 5.3.1 Ray Tracing and Translucent Shadows

Development Rendering
1

I’m trying to understand what I’m missing when it comes to translucent shadows and ray tracing. I recently tried enabled ray tracing in my project, and it looks great, but particles that used to cast nice shadows are no longer working as expected - with ray traced shadows, the whole sprite is creating a solid square shadow. I’ve attached a before and after pic.

I’ve looked through every light, material, and project setting I can think of. Anyone know what I might be missing, or is this just a problem with ray tracing in unreal 5?

noraytracing
noraytracing717×592 334 KB

raytraced
raytraced808×666 412 KB

2

Yikes, looks like this is a known issue? This youtube video shows an extremely janky workaround for 5.2, which sounds very clumsy (but not impossible) to pull off with particles.

3

Translucent shadows aren’t supported by hardware raytracing, see the docs: Hardware Ray Tracing in Unreal Engine | Unreal Engine 5.3 Documentation