No no, I explicitly said "ahead of time". It's easy to determine what's on screen when you're about to render the frame, but you have to load every single object in memory because every single object is a "candidate" that may end up on the screen, you just don't know ahead of time. You can't cull the voxel tree, even though 99% of the voxel tree won't be used when rending a frame. So the memory overhead is immense.

Voxel trees don't make it easy to discard things that are far away at all, because there aren't any low-resolution objects that you can use for far-away objects. You have to load many objects in memory even when you use them to render just a pixel or two.

The polygon-based worlds we have today use various low-resolution models for when you view at a distance, and as you get closer the higher resolution models "pop in". This tech advertises that you have infinite detail and that there's no need for objects with different level of detail. This means that the complete point cloud of every object has to be loaded in memory and that's a very real problem and it's in complete contradiction to the claims made by the company that artists can create infinitely detailed worlds without having to worry about vertex counts or whatever. Artists have to compose their world out of re-usable high-detail objects or the sparse voxel octree will be way too large. This means the artists will be much more constrained than they are today, not less.