What is causing "shadow banding"

[Core]

Hi!

I have noticed this here and there every once in a while, but now that I'm finally building a map with aesthetics in mind, I think it is time to dig deeper into this. So what is causing this banding with shadows, and how I'm able to prevent it from happening? I understand that it must be some kind of limitation with the engine, but just knowing how to avoid it would be awesome! Thanks again for any tips.

Edit. Oh, numerous times I've been asked to send a map for an example. I would, but noobish question... How? What files I should include? Is there an easy way "create" a file that includes everything you need to run a map on another computer? Thanks again.

[Core]

Jesus, I got it! First of all, it only happens with spotlights and if you have more than one on the same area. Point lights cause no banding/stripes. With spotlights, you can greatly reduce or even get rid of it by randomly rotating them around Y-axis to make sure they are not "lined up" with each other.

 First image shows situation where banding occurs:

And here all four spots are rotated randomly around Y axis, and banding is gone:

[reepblue]

This is a side effect of the real time lighting system. All modern engines have this issue and ways they try to mute it; most commonly baking the lighting.

A while back, Josh was experimenting on filtering out but this resulted in everything looking grainy. The code is still in the shaders commented out if you want to experiment with it.

[Josh]

If you set the lighting quality to a higher value it minimizes this effect. You can also mess around with the near and far range in the light settings.

[Core]

Ok, good to know! Since Leadwerks is actually THE only modern engine I have ever used, there is so much basic stuff I need to learn... But nice to know there are ways to overcome this.