Subdivision based on camera distance

[Maximus]

Hey, i was wondering how is it possible to control the subdivision of an object based on camera distance.
I have an heavy scene with lots of objects, many in the background, is there a quick way to tell MR to render them at another Subdivision level since some of them gonna even be blurred by DOF?

[Mathaeus]

You can write an expression in geo approx ppg, I think that's all. Last time I've tried this, around XSI 6 or so, it causes crashes with motion blur. BTW SI does subdivs, not MR. In short, I think answer is no.

P.S. anyway expression could be something like:
cond ( ctr_dist ( Camera. , this. ) > 55, 0, 1)
which means, if distance from Camera, called exactly "Camera" is higher than 55 units, geoapprox switches to zero, otherwise is 1. Might work with static scene.

[Saturn]

As Mathaeus said XSI does the subdiv before to send it to MR. XSI doesn't use the subdiv of MR which support view dependant tesselation.

A silly trick that may work ( or not ) is to have a displacement shader ( a scalar_save_state set to 0.001 ) in the object. Make sure that you set your geo approx to view. Dependant on your mesh, but you may have the curvature to look different.

[iamVFX]

Don't know why nobody has suggested ICE. Every parameter from a scene can be dragged into an ICE tree, then copy the path of the parameter to Set Data node.