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Cascade Shadow Maps Flickering!!! (Mobile)

Hey guys I’m working on a mobile game. I have a huge problem and I don’t know if it is a bug! I’m using a directional light, stationary but it’s not working at all. In some points of the map the shadows starts flashing on and off like something’s broken (yes, like a disco if you’re asking haha). I tried to change some parameters but I can’t find a solution. Any idea? I really hope some of you have an answer for this. I’m using UE 4.25 Thanks guyssss

What materials are used in the areas with the flashing / flickering? What are the CSM settings?

simple materials with roughness, color and normal

It could be something other than CSM. The distance is a bit short at 2000, so viewing from the camera while moving it around could produce a bit of sharp transition at approximately 2000 units away from the affected areas. But I don’t think this is the case because it’s a stationary light, and the Transition Fraction is 200, which means it would have to be moving super fast to get such a fast transition that it appears to be flashing on and off.

Is ray tracing on for the scene? what are the reflections settings? There’s often flickering and flashing with ray traced reflections in certain things, and it can also happen without RT enabled. Try a few visualizers, such as lightmap density and Unlit, and do a stat GPU by typing ` to bring up the console and type in “stat GPU”. Look for any large increases in memory use when viewing the flashing / flickering effect in the viewport. I’m not sure what else to suggest, currently.

I have no RT on the scene. I thought about the culling on the back of the camera…may be this the problem???

Just wondering is this the same problem that you were seeing? This happens for me on ES31 rendering preview (and on devices), it is very weird, the shadow render perfectly on the same map with SM5. If I decrease my CSM distance the problem goes away, the symptoms happen when the distance is set at 30000 but dropping it to 20000 completely stops it from happening.