Same Material, Different Shading

[Anonymous]

I noticed that when rendering a façade in AC10 the materials of the walls and the slabs are shaded slightly different. I checked several times that the materials selected are exactly the same. Even with another material the effect remains the same. What am I overlooking?

This difference in materials is not visible in OpenGL, only after rendering in LIghtWorks.

Any assistance is appreciated.

Florian Techel

[stefan]

Are they actually modeled like that? Can you show a section through that facade? This might come from overlapping surfaces.

[Anonymous]

stefan wrote:
Are they actually modeled like that? Can you show a section through that facade? This might come from overlapping surfaces.

Yup! Wall, slab lays on top of wall, upper wall stands on slab, and so on. The material allocation around the perimeter of the slab is exactly the same as that of the walls.

And I did check meticulously that the objects (walls and slabs) do not intersect each other.

Florian

[Thomas Holm]

Don't know the reason for this, might be that Lightworks interpretes a direction in the material, and the direction differs.

The cure is obvious though: Model it as it will be built, that is shrink the slab a little and fill the gap with a thin wall with the same material as the rest of the walls.

[Anonymous]

Thomas,

You are correct. It must have something to do with the orientation of the objects, because a wall, once mirrored or rotated 180 deg, changes its shade slightly (that tonal difference).

That means, yes, one has to design it with that slim sliver of a wall outside of the slab, which is, of course, more work.

Still, I don't get it. I thought that these textures are infinitely thin and that therefore the orientation towards the light should not really matter.

Thanks,

Florian

[Anonymous]

Rather than add all those little scraps of walls you can also shrink the slab to the inside face and extend the lower walls to the top of the slab.

[Laura Yanoviak]

...and there's always SEOs...