Switching ribbon trails emission glitches transparent materials

Hello, I’ve encountered a weird problem lately.

I’ve been struggling with this for a few hours.

If I spawn a few objects that use any of material that has transparency, (or material that has ALPHAMASK psdefine)
and then I spawn some ribbon trails and after a short amount of time I destroy them and spawn again very quickly, I can see some glitching, the materials with transparency are weirdly flickering, which you can see there:

flickering cat boxes (not virus)

It also happens when I’m quickly switching their emitting by SetEmitting() function. In the video I spawned like 100 of ribbon trails, but this glitch seems to appear independently of their count.

For ribbon trail I use default SlashTrail.xml material, but If I change its technique to non-alpha, the flickering disappears.

I encountered this problem when working in my game where I switch ribbon trails often, and manipulate their’s lifetime to give them better look, but I can’t stand this flickering.

I’m using Urho 1.7

Do your transparent materials provide all the textures they should be (e.g. you actually have an normal map for DiffNormalAlpha), and were all of them successfully loaded? I sometimes slightly similar effects when a texture wasn’t found where a model will flicker between multiple different patterns based on model happened to be rendered before it.

Also, I would recommend switching to the master branch. There is a chance that you’re encountering a bug that has since been fixed. Maybe something like this:

I’m pretty sure it’s not about textures since I know this bug and checking it was one of first things I’ve done.
I will test if it happens on never version though.
Thanks for tip.

I checked and it still happens on newest Urho. :frowning_with_open_mouth:

Is anyone able to reproduce this?

Can you produce a minimal example that exhibits the behavior for people to test?

Yes, thanks for reply
sorry for late response, haven’t had much time lately, here’s example: example

I placed there code and assets, example has only CatCube material, Cat texture and DiffAlphaMask technique added to standard Urho assets, I also modified EP_RESOURCE_PREFIX_PATHS in Setup method but forgot to change that, so set it to your project name.

Anyone getting similar results?