question

José Varela avatar image
José Varela asked ·

How can I invert a normal map in a symmetrical part of an object?

I have an object with an unwrapped normal map, to which I apply a symmetry modifier in 3ds Max. The problem is that the normal map gets inverted on the symmetrical part of the object. Is there an easy way to fix this problem, without having to create a new material with the tangents flipped for the symmetrical part of the object?

Tank you.

10 |600 characters needed characters left characters exceeded

Up to 5 attachments (including images) can be used with a maximum of 2.0 MiB each and 9.8 MiB total.

José Varela avatar image
José Varela answered ·

I think there are some 3d rendering engines (such as Mental Ray or ART renderer) that identify automatically when a symmetry was created and would invert automatically the normal map. Do you know if Arnold also capable of doing this?

Thank you.
Share
10 |600 characters needed characters left characters exceeded

Up to 5 attachments (including images) can be used with a maximum of 2.0 MiB each and 9.8 MiB total.

José Varela avatar image
José Varela answered ·

Thank for your answer Lee.

The problem of applying the Invert XYZ to the material is that it will correct the symmetrical part of the object, but at the same time it will also invert the original part of the object. Then the symmetrical part will be ok, but the original part will be inverted, since both parts belong to the same object, to which a single material is applied. Maybe the only solution is to create two materials, one with the original XYZ, and the other with the inverted XYZ, and apply the to the original and inverted parts of the object respectively. However, this looks like an old fashion solution for the renderer the is supposed to be a modern, state of the art tool.

Share
10 |600 characters needed characters left characters exceeded

Up to 5 attachments (including images) can be used with a maximum of 2.0 MiB each and 9.8 MiB total.

Lee Griggs avatar image
Lee Griggs answered ·

Have you tried Invert XYZ?

Share
10 |600 characters needed characters left characters exceeded

Up to 5 attachments (including images) can be used with a maximum of 2.0 MiB each and 9.8 MiB total.

José Varela avatar image
José Varela answered ·

This is what I get when showing the normal map:

And this is what I get when rendering the image:

The lighting on the symmetric part of the object is not according to the normal map.

Does any6one knows how to solve this problem?

Thank you.


image1.png (106.7 KiB)
image2.png (578.6 KiB)
Share
10 |600 characters needed characters left characters exceeded

Up to 5 attachments (including images) can be used with a maximum of 2.0 MiB each and 9.8 MiB total.

Write an Answer

Hint: Notify or tag a user in this post by typing @username.

Up to 5 attachments (including images) can be used with a maximum of 2.0 MiB each and 9.8 MiB total.

Welcome to the Arnold Answers community.

This is the place for Arnold renderer users everywhere to ask and answer rendering questions, and share knowledge about using Arnold, Arnold plugins, workflows and developing tools with Arnold.

If you are a new user to Arnold Answers, please first check out our FAQ and User Guide for more information.

When posting questions, please be sure to select the appropriate Space for your Arnold plugin and include the plugin version you are using.

Please include images, scene and log files whenever possible as this helps the community answer your questions.

Instructions for generating full verbosity log files are available for MtoA, MaxtoA, C4DtoA, HtoA, KtoA, and Kick.

If you are looking for Arnold Documentation and Support please visit the Arnold Support site.

To try Arnold please visit the Arnold Trial page.

Bottom No panel present for this section.