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3D Volumetric Ribbon Emitter?

Is it possible for a ribbon emitter to wrap into a cylindrical shape? Basically I have a ribbon emitter trail that I would like to be more of a ‘tube’ than a flat ribbon. I assumed that would be to do with the material, but after an unsuccessful night of trial an error, I’m not sure it’s even possible.

Plan B: If that’s not possible, what’s the best way to deal with the hideous artifacts created by overlapping transparent sprites in a ribbon? Where they overlap (esp. on tightly curved segments) the translucency builds up and creates all these hideous, opaque triangles; can this be avoided?

it is not possible to have actual tubes with the ribbon emitter.
if you need it to appear to be tube-like shading wise you can possibly use the splinethicken node in the material editor.
if you need an actual tube geometry your other option would be to do it via blueprints and splines. bill kladis has made spline-based mesh trails, but you’d have to ask him directly to share it.

for the overlapping part - the only “easy” solution i can think of would be if you can have the ribbon render to the custom depth buffer and cull based on that.
http://www.tomlooman.com/the-many-uses-of-custom-depth-in-unreal-4/ under “culling inner triangles”

@divi - Thanks! That spline thicken works perfectly! I wish I hadn’t spent a whole day trying to get sphere gradient 3d to do that job…:rolleyes:

If I could get one more tip on this subject…I got this all working pretty nicely now, but the trails come off the ship at sharp angles when turning quickly. I need some way to give the ribbon more “rigidity” at the source, then falling off to what the natural curves are doing already.

In other words, can I cause the ribbon to be completely straight for a short distance, right where it starts, before gradually allowing the ribbon curvature?

bump…can anyone point me in the right direction for the question above?