[gtalarico]

I have been experiencing disapearing components when "Use instances" is turned on.
It randomly "hides from camera" chunks of components in my model (shadows are present).
Disabling it fixes, but export time increases by a lot... Is there a fix?

Normals are ok...
When I export to studio, it looks ok.
What is weird too, is that if I copy and paste the components into a fresh file, it looks ok... Could it be a memory due to model size?

I am using 2.6.1

http://i.imgur.com/Kr5tC.jpg
http://i.imgur.com/73yr7.jpg

PS: among the selected components seen in the screenshots, there are 4 types of components randomly scattered, but somehow they always disappear in perfect rectangles!

[gtalarico]

This might explain what I attempted to explain in the "PS":

http://i.imgur.com/TQGbb.jpg

[JDHill]

First, when you write "hides from camera" do you mean that, checking in Studio, the Hide from Camera property is actually set, or do you just mean that the objects look as though they are hidden from the camera? Second, if you delete everything out of the model, except for several of these floor tiles, are you still able to observe the issue? If so, could you send me a simplified copy of the model (with unnecessary stuff purged out)?

I suspect that it has to do with an obscure bug in the engine, and that if you rotated these components by even a tenth of a degree, the issue would disappear. Not saying you should be required to do that, but just that this should be the case if it is indeed what I suspect (which is: issues with axis-aligned faces in axis-aligned instances).

[gtalarico]

the objects look as though they are hidden from the camera

Exactly. When I export to studio, the render ok. They are invisible, but cast shadows.

I haven't tried deleting stuff, but I did try pasting all the tiles in a new file, and they rendered ok.
(I tried to isolate them to send it to you, but they rendered ok when isolated in a new file...)

I thought about the rotation as well, and I used Chris Fullmer's "Mass rotate" to rotate every component 180 degrees. Didn't work. (Perhaps because I rotate the component, but not the geometry inside?) Or does the rotation needs to be non-orthagonal...?

What is strange is that if I delete the missing tiles, and I copy new fresh ones in, they still don't render... (sometimes it works, but 90% of the time it doesn't.)

As I mentioned before, in any of these cases, turning off instances solves it.

[JDHill]

Yes, if I am correct, then a) it could be seen on faces of an instance or its mesh, and b) faces involved would be axis-aligned. If so, as you guess, a 180° rotation would not help. Unfortunately, it is something in the engine, and that is all I can tell you about it. I have never been able to reproduce it deliberately from scratch, but I have a file I got from a customer where it was consistently reproducible using a very clear set of steps, and the core engine developers have been looking at that. The only viable workaround for the time being appears to be turning affected components into groups, to prevent them from being instanced.