Frustum VDBs in Karma

   3627   6   1
User Avatar
Member
61 posts
Joined: April 2017
Offline
Hi!

Will it be possible to support camera frustum VDBs in Karma? They are essential for water fx work when rendering whitewater, it'd be great to be able to render them.

Thanks!

Miguel
Edited by Megalis - Jan. 31, 2021 06:25:18
User Avatar
Member
164 posts
Joined: Nov. 2012
Offline
I think this is a critical feature for Karma to have. It enables many great techniques to get high quality volumes rendered in a fast and efficient manner!
Edited by MattPuchala - Feb. 2, 2021 14:50:23
Matt Puchala
www.mattpuchala.com
User Avatar
Member
8041 posts
Joined: Sept. 2011
Offline
I never thought to try this with karma. Are they currently broken? I haven't used frustum vdbs in a few years.
User Avatar
Member
61 posts
Joined: April 2017
Offline
Yes, right now trying to render one gives a black frame.

In our case, we always render whitewater as a frustum VDB, and many fire/smoke sims get rendered the same to do operations that push the detail and for the great speed up in rendering you can get, so it is a big feature needed if we want Karma to render fx elements.
User Avatar
Member
167 posts
Joined: Jan. 2019
Offline
Just out of interest, 'camera frustum VDBs' Is this culling the VDB by the camera's frustum at render time, or something more complex?
User Avatar
Member
8041 posts
Joined: Sept. 2011
Offline
daviddeacon
Just out of interest, 'camera frustum VDBs' Is this culling the VDB by the camera's frustum at render time, or something more complex?

Not specifically, no. However, they will not contain anything outside the frustum by their nature. A frustum volume is a volume grid that is frustum-shaped, instead of box-shaped, and hence all the voxels are frustum shaped. This has the property where voxels closer to the camera are smaller than those far away, leading to the volume containing just the right amount of information for maximum detail.
User Avatar
Member
2 posts
Joined: May 2014
Offline
Does someone know how to use : "VDB Rasterize Frustum geometry node" ? What are differences with other vbd nodes ?
Thank you.
  • Quick Links