Displacement on Create Polygon Tool

#1

I have a material wich I render with Mental Ray with a displacement.
When I create an plane and uv map my material it renders perfectly.
When I create a plane with more subdivisions and move some vertices it still renders perfectly.

But when I create a freeform face with the create polygon tool and map uv map is, i does not render perfectly. I looks like i does something with the displacement, but i can hardly see it.
I freezed the transformations, but is did not have any effect.
It also happens when I make a simple rectangular face with the create polygon tool.

Can someone help me ?

#2

I’m not able to recreate any kind of problem. :shrug:

Displacement relates to object size, so maybe that’s it? Even if the transform is frozen.

#3

Tnx for your answer.
I tried it serveral times in Maya 2015.

In the attached image you can see the models.
The plane in the middle is the one created with the create polygon tool.

#4

I test the following: i scaled the object by 0.01
Then i freezed the transformation and scaled the object bij 100
When I render it look okay.

Does it not base the displacement completely on the UV’s ?

#5

That’s very strange!

The layout is based on the UVs, but the displacement amount is not. If you use a 32bit displacement map from ZBrush for example, the pixel values are literally representing scene units. So a pixel value of 4 will push out the surface by 4 Maya units. If your object is tiny, 4 units is a lot, if it’s a huge building it will seem hardly noticeable.

It looks like you may have found a bug though in Maya 2015! I’m not sure why scaling it up/down fixes it.

#6

I found out that when i scale the object by 0.004 and than by 250 i have almost the same result as with the planes. So it looks more like a inch centimeters difference…

I tested it in Maya 2016 as well. I had the same problem.