Textures invisible through reflective material

09 December 2014 19:05
Hello again guys, sorry to bother with another question.
I am getting unintended culling in textured materials when seen through an object with reflections enabled, disabling the reflections makes it render correctly again.
This is a new project I am working on, the image below shows what I mean.

As you can see the interior of the model has a wood material with an image texture, but it doesn't render when seen through glass panes with reflections enabled. You can see it correctly through the left-most door and the second window from the left.
The other ones (first and third window from the left) clip the material as if the normals were facing away (and they aren't, I have checked), the white material which has no textures renders correctly.

Is this a bug, an unsupported feature (rendering textured objects over reflections), or am I doing something wrong?
09 December 2014 20:03
Hi Duarte,

We got a reflection test here (attached) - please check your and our settings. BTW, we currently support plane reflections only. If you need window reflection you may probably want to use cubemaps instead of dynamic reflections (e.g. like on the sports car windows).

Looking at your screenshot - does the yellow material have alpha blend setting enabled too? The conflicting alpha blend surfaces could be a likely reason for this disappearing.

Edit: the transparency should not have any effect on reflectivity, e.g. water in this demo perfectly reflects things.
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10 December 2014 04:52
Hello, thanks for the reply, I checked my reflection settings and everything appears to be in check according to your example.
The yellow material is a simple yellow diffuse material, no reflections or transparency to cause alpha conflicts (it looks up transparent in the screenshot because from that viewpoint with the wood missing we are watching it's backface).

It's probably what you mentioned, since reflections are only supported on planar objects there must be some sort of glitch at work here, the windows are mostly planar but there is a slight slope on the lower panes. It is probably best to simulate the reflections with cube maps anyway, like the car example which looks very very good.

Thanks for the help
10 December 2014 21:18
Okay, let us know about any problems you meet. Still the issue you encountered feels like being a bit buggy or strange at least. If you think it's worth seeing it you might provide us with a small test scene.
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11 December 2014 01:53
Ok, so I've been testing it further and have not been able to recreate the problem in a different blend file, even importing exactly the same objects with the same materials. Maybe it's something bugged in the blendfile it'self, or I screwed up something along the way, because it as already rendered correctly in the past.

Anyway the problematic file is attached, maybe you can find out what is wrong with it (if anything at all) and so is the resulting HTML. If zoom in close enough to enter the tram you can see the interior has the wooden material, which is not visible through the windows.
In the meantime I'll probably try importing everything to a new scene since that seems to solve it for now, and maybe look into using cubemaps.
Hope the attachment helps, thanks for the suggestions
11 December 2014 10:14
I made your "Wood" material opaque and it is now shown correctly through the windows.

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11 December 2014 10:14
Nice model by the way
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11 December 2014 21:23
Wow that was it?? Must have inadvertently changed it by mistake instead of the glass material.
I would have never found out about it thanks a lot for the fix.

Thanks glad you like it. It's a Lisbon tram, I plan on posting it in the projects section later with full info when it's finished

Thanks again for the help
06 May 2015 15:15
Very good. I also did the same tram in the past:
06 May 2015 15:22
Wow cool model, render looks fantastic.
I haven't been able to get back to this, it's been on hold ever since, but I still plan on finishing it.
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