Two Material issues with AO

One: There is a material within a group that AO hates. It will not render it. I can get it to render if I go in an reapply it before I render (after I have tried once) or sometimes if I change its name but that does not consistently work. I have tried to make a exception for this material in the material editor but that did not change anything. Is there some way to stop this from happening?

Two: This one has changed in the last 2 months (not sure when the last time I used this texture was). A few months ago the material rendered as it should. Today It is scaling it from 12’ to approximately 1’ scale when it renders. I have tried doubling the scale, nothing changed. I tried changing the scale while it was rendering hoping it would recognize the change, still no change. (so instead of looking like a nice texture it looks like a bunch of tiles…)

Can you please send us a simple model reproducing the problem, so we can take a look?

It is a work model so no. I can link a couple pictures.

How it is being rendered. Tiled material is suppose to stretch the whole bed spread. The pillows are rendering shiny.

Second is how it is suppose to look but the pillows are stil shiny.

After changing to a different material.

What the materials are suppose to look like.

After copying the group in the photo above to another file changing the color and bringing it back.

I have noticed that it is fine when it it first brought in but after I change the color of the material it became tiled. It only is doing it in the work model I can not replicate the bug new file. This file is very large 703,7775 edges, 312,961 Faces, 335 materials and 1087 groups. I nest groups in groups.

If I copy the whole model over to a new file it will still do it. If I copy it in pieces it does not. If it starts doing tileing have to get a new version of that group. It will not fix it to make the material default and then replace the material.

The red pillows is the original color of the material. If I re- place the material on the pillows and change the color again they should go back to the way they should be.

It seems to be something going on with groups and how the program is getting information on how to display the material.

I have spent 45 min trouble shooting for you to get these pictures and trying to get it to replicate the problem in a file that does not have our full model in it. I can not spend any more time on this problem you guys will have to do your own trouble shooting from here. I am happy to answer questions to try to clear things up. I would suggest maybe downloading full models off the warehouse and testing the renders and look for changes in the materials.

Some more examples of material issues. The first one is an auto for the rock material. It is scaled up a bit and I have a similar issue with concrete with the auto material.


The second is an issue with water as a thin dielectric, looking through the thick dielectric of the window. When I change the index the water goes black (like when you have the index at 1) and no matter how far I turn it up it will remain like that. I am also having a hard time getting the water a more transparent. For this model I had to just go to a higher bump and have choppy water.


Sorry I cant upload models but they are for work and they do not want them uploaded anywhere. Also my last post was not suppose to be snippy, but I did not want to use more of my employers time to troubleshoot bugs.

I would like any assistance on these issues. Here is another one. The ceiling is made glass on the back side and default on the front. In the picture you can see it is rendering the glass and the roof shingles which are on the outside of the next material…

Also it would be nice to be able to switch the background through windows. No matter the background I choose this is what I get. but only looking through the windows…

AmbientOcclusion always uses the material assigned to the front face for both the front and the back material. Please make sure to assign the proper material to the front face.

Thanks for the response. I am aware of that which is why I mentioned it. The back side (with glass) is above so that when you look at the house with the roof off you can see how the ceiling works but when you are inside you have the white front face for the ceiling. The Roofing material was also on the outside but I resolved that by re applying the default material and adding thickness to the roof.

I love what this renderer can do fast. I am rooting for it but there are some definite frustrations when working with it. I suspect it is something to do with groups that are nested in groups and how that interacts with how it chooses it’s materials. Because a lot of my disappearing and wrong color problems are with groups that are within other groups.