Question by SGT_Smith · Feb 11, 2017 at 06:06 AM · camera rendering shadows bug-perhaps

Using multiple cameras for different render distances causes weird shadow effect?

I'm using multiple cameras to render certain things at different distances (ie: grass). I tried doing this with a depth only camera seeing only grass, but that allowed me to see the grass over everything, so i opted for the far camera to start at Near Clip 15, and the near camera to stop at Far Clip 15 and both render everything except only the near cam renders grass.

However on doing this im getting very strange shadow behavior: https://i.gyazo.com/7535e46a4b59be784fc07f1752ede773.mp4

Its most noticeable on the left and right but does it on the center as well in some spots.

Far Cam: https://i.gyazo.com/2b2f44161e4ead6475df88e344ce31d3.png Near Cam: https://i.gyazo.com/baafecfea74095ba2622f5b3c55dfd53.png

Any ideas for a fix for this?

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hexagonius · Feb 11, 2017 at 08:59 AM 0

the same behaviour of rendering things at certain distances can be achieved using LODs. check it out. the problem is that both cameras have different information about shadow casters they see (near only up to 15, missing the rear wall ), and on top try to render the same data on top of each other.I'm not sure about this one, but it could cause z-Fighting, the same effect as putting the same object in the same place twice, where the camera can not disgusting between them anymore and the surface flickers.