LuxCoreRender Forums

Sharlybg wrote: ↑Wed Oct 23, 2019 1:43 pm Just why it doesn't work if the "Cube" volume object totally surround the camera ?

Because it never worked that way.
Camera volume will work for you if you have no more than one volume in you scene.

Also the idea of "external volume" seems a bit funny to me. Because if I have a dusty room with a table, on which glass is stading with liquid in it and a straw half in liquid, half in air, I am a bit confused – what's external volume for what? Is it all air? For straw too?

wasd wrote: ↑Thu Oct 24, 2019 9:48 am Because if I have a dusty room with a table, on which glass is standing with liquid in it and a straw half in liquid, half in air, I am a bit confused – what's external volume for what? Is it all air? For straw too?

Thanks to the priority of volumes, indeed, the best way is to define air as external volume for all of them (assuming air has the lowest priority).

Sharlybg wrote: ↑Wed Oct 23, 2019 3:36 pm

You have to set the camera or world volume.

Set as same as my cube volume or a new volume ("air") ? anyway i've done both and it doesn't work.

You delete the NULL material box and set the world volume to your air volume. Scene attached to this message.

In a new scene, you have to:

1) set the world volume to your air volume.

Nothing else.

Dade wrote: ↑Thu Oct 24, 2019 1:39 pm In a new scene, you have to:

1) set the world volume to your air volume.

Nothing else.

Technically correct, but if you do that, all infinitely far light sources (like the sun) become more or less unusable because their light is scattered all the way from the scene bounding box to the camera (as far as I know).

If you want to limit the extent of the fog, you can use a fog box, but you have to set the camera volume to "fog" (if the camera is inside the box) so the rays start in the correct volume.
If that does not work, it might be a bug.

If that does not work, it might be a bug.

so it is.

I'm getting some pretty weird behaviour in a test scene I set up (mismatches between viewport and final render, foggy scene despite fog volume not being used) and I suspect that there are some bugs in BlendLuxCore in this regard.

B.Y.O.B. wrote: ↑Thu Oct 24, 2019 1:57 pm
If you want to limit the extent of the fog, you can use a fog box, but you have to set the camera volume to "fog" (if the camera is inside the box) so the rays start in the correct volume.

Setting camera volume never worked right if you have at least 3 volumes in your scene.

https://github.com/LuxCoreRender/LuxCore/issues/220