Vray Camera Clipping and GI solutions

[tricky]

Not sure if this is a problem or a wishlist - make up your own mind.

We are working on an image where we need to use the clipping plane of the vray camera. Its a slightly stylised perspective cutting through a multi-storey atrium.

I've yet to check this out, but is the GI calculation affected or unaffected by the clipping camera. Ideally, I need it to be unaffected.

We are using Vray 1.5 and Max 2009 x64.

[DanielBrew]

It depends what you mean by unaffected. If you mean will will the interior be overexposed then the answer is no, the lighting inside the atrium will be exactly the same. But the IR map is view dependent so GI won't be calculated for objects behind the clipping plane. So in that respect the GI will be affected.

[tricky]

Bugger.

I had hoped clipping would only come into effect at render time and not during the calc of the IR map.

Would an alternative GI calculation method be more suitable in this case?

<EDIT: how about saving the solution with an unclipped camera and then using that with the clipped camera? Would this enable me to use IR Maps?>

[DanielBrew]

You should be able to animate your cut plane from 0 to the final position over about 25 frames. Then render your GI with multiframe incremental. You should then have a saved GI solution that has samples on everything you need.

What exactly are you trying to do?

[tricky]

You should be able to animate your cut plane from 0 to the final position over about 25 frames. Then render your GI with multiframe incremental. You should then have a saved GI solution that has samples on everything you need.

What exactly are you trying to do?

Basically, its going to be a composite image showing a cut through of an atrium. The reason for the cut/clip is that the view is impossible without it: effectively it is a sectional perspective.

Note this is a static image only, not an animated 'cut through' - I may have mislead you.

[DanielBrew]

As long as you have lights inside the atrium or enough glass to let light in you should be ok with irradiance map + LC.

What meant in my first post was using a camera with a clipping plane to see through a wall is not the same as removing the wall. Environment light won't flood into the interior.