[SOLVED] Omni lighting artifacts on close objects when a large shadow map size is set

[mathias.poupard]

Hello,

 

I've got a question about an issue we met with "omni" lights: as we increase the size of the shadow map, very noticeable artifacts appear on illuminated objects that are close to the light source.

 

On both screenshots attached, using the "cool materials" demo, the radius of the light is 10 and the shadow mask is 0x3f. On the screenshot where the artifact is not visible, the shadow map size is 512, and it is 4096 on the other one where the issue arises.

 

Is it to be expected? Do we have to check object proximity before increasing the size of shadow maps?

 

Thanks in advance.

[frustum]

What value of the light shadow bias/slope parameters?

Try to increase them.

[mathias.poupard]

Hello Frustum, thanks for the quick answer.

 

Shadow Bias and Slope values were both at 4, which is their default value I guess. Increasing them to 8 to 16 give good results in our scene.

 

We will experiment to see what ranges of values are best for us according to the current size of the shadow map.

 

Thank you.