Something wrong with VrayDirt ?

[pixela]

Hi,
The radius parameter is behaving strange.

Here are the renders to show the problem.


Did something change with VrayDirt or am I doing something wrong?
PS: All the meshes are reset Xform and scaled to 100%.

[Neilg]

your object is shelled, i presume? probably about 2.5cm thick?

[pixela]

Thanks for the reply.
No it is not shelled. It is editable poly without shell. Only UVW modifiers on top and nothing else.

[Morne]

I think what cubiclegangster meant was that your object is too thin for a radius of 3cm

For a test, increase the thickness of your objects and see on a radius of 3cm if you still get the darker version.
A workaround would be to use edgestex in diffuse maybe?

[Neilg]

No it is not shelled.

it doesn't have a thickness?

[alexyork]

The thickness (or lack thereof) shouldn't make any difference, since the occlusion is calculated across each face independently, no? This looks like a bug or something else strange happening to me.

[Macker]

Thickness sadly does make a difference. A while back I put in a request that vray dirt have an exclude self option, but nothing has come of it yet.

[alexyork]

Thickness sadly does make a difference. A while back I put in a request that vray dirt have an exclude self option, but nothing has come of it yet.

Really... first I've heard of that. Will look into it. Never had any issues like this myself.

[Macker]

http://forums.chaosgroup.com/showthr...t-Exclude-self

[pixela]

The thickness (or lack thereof) shouldn't make any difference, since the occlusion is calculated across each face independently, no? This looks like a bug or something else strange happening to me.

I thought the same that each face is calculated independently.


The object has 2cm thickness.
So probably that is why 2cm radius is doing fine, while 3cm radius is being calculated strange.
But was this always how vraydirt behaved?
What happens on a plane without a thickness? I must test.

[pixela]

The same material is applied to all the 3 objects in the render.
VrayDirt Texture settings are in the image - with a radius of 15 cm

Test shows that thickness is taken into consideration and is not calculated for each face.

[Neilg]

it's always been like this, it's because you're inverting the normals. you don't see it when the dirt is set up with that off because it's looking in the opposite direction.