Decal issue

FEMTO · Jan 2015

I noticed something strange when standing from a distance a shadow/black outline appears on my decals which I don't want. When I approach the decal it disappears. Anyone have any ideas what is causing this issue?

Cast shadow is unchecked in the properties of the decal.

Vailias · Jan 2015

Sounds like a mipmapping issue.
Do your decals have black as a background color in the texture?

FEMTO · Jan 2015

No they do not

Vailias · Jan 2015

huh.
Could you post a screenshot or two? Might help.

FEMTO · Jan 2015

See attached file - so what you can see is a dirt decal applied to the bottom edge of the wall and there is a black shadow appearing when viewed at from a distance.

FEMTO · Jan 2015

Another thing I've noticed is that if you look at the decal dead straight the shadow disappears but when viewing at an angle it appears.

FEMTO · Jan 2015

Ok I have found a solution of some sort which is that I adjusted the depth bias parameter from -0.00060 (default setting when decal is applied to a surface) to -0.00010, which seems to work especially from the distance that I wish to view the decal at.

Having said that, if I were to fly up and move even further back the black outline reappears. If I were to set it to a value of -0.00000 or higher than the Decal will as you'd expect disappear entirely. Therefore the problem has not really been resolved.

Still would like to figure out a proper solution to this problem

Cay · Jan 2015

that's the biggest image i've seen in a while..

Vailias · Jan 2015

I haven't tried to replicate this yet, but just to be sure, your material shading type is set to decal and not surface, yes?

FEMTO · Jan 2015

Sorry can you clarify what you mean. Not sure where I should look to see if this is the case or not. thanks

FEMTO · Jan 2015

Ok, I figured out a permanent solution. I decreased the Far Plane value from 300 to 10 and that has now resolved the issue. Thanks for your help anyway!

Vailias · Jan 2015

Glad you solved it.
What I was talking about is in the material properties:
https://docs.unrealengine.com/latest/INT/Engine/Rendering/Materials/MaterialProperties/index.html#material

See where it lists "domain"?
That's where I was talking about if it was set to decal or not.

FEMTO · Jan 2015

Oh I should have pointed out that I am using unreal 3

Ramseus · Jan 2015

I know exactly the issue, I ran into that myself mainly on instances where I put a decal down to try to blend a static mesh and landscape. It's like the sorting gets messed up and the shadowed mesh gets rendered on top some how. I never figured out how to actually fix it, but if you're able to get away with an unlit decal, that'll be seamless if you get the color right (only works in full light/shadow, of course). Meh.

Unreal, y u sort so bad?

Decal issue

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