displacement changes the look of specular materials

[bartolos]

Hi,
As soon as I enable displacement on a specular material, the refraction starts looking very different, even if the displacement is negligible.
The effects are as if the refraction index was boosted highly, and a ring of total reflection appears beyond a certain camera angle.

No displacement:

Displacement set a 0.01 magnitude:

Cheers,

[bepeg4d]

Hi bartolos,
what kind of displacement texture are you using?
What about uv and scale?
Could you share a screenshot of your material?
ciao beppe

[atome451]

Hi all,

Just an idea. I think you don't have overlaping for the water inside your pool. Polygons of the water are exactly adjusted to the polygons of the pool. Maybe a copy of the box for the water before modeling the pool?

When you activate the displacement, the mesh of the pool is a little bit smaller and is overlaping the mesh of the water. The result you obtain is in fact the right simulation of the index.

The water needs to overlap the pool for a good result with Octane (the same for a glass with liquid, a cup of coffee,...). If i'm right, you should work on the index of the water material to have the right effect and overlap a little bit the water to be sure it overlaps everywhere.

I hope this will usefull.

[bartolos]

Hi,
Thanks for the replies guys.
It seems the problem was scene specific... I don't know why when I deleted and created the pool surface again the problem disappeared ... weird.

My scene is very simple - the swimming pool is just a pit (side walls and bottom only), while the water surface is just a plane. It is not a closed volume by itself. But it consitutes a closed volume with the swimming pool bottom and walls. As you can see it works as expected when there is no displacement involved. As soon as i enable displacement on the water surface it breaks the refraction.

Anyways ... nevermind.
Cheers