Vray Displacement with viewport functionality / preview

[Dmerc]

Especially working with terrain displacement maps, that would be handy. Using just use one Vray-Displacement modifier on top of a plane. In the viewport it would basically work like a regular native displacement, while during rendertime it works as usual includung the subdivisions.

Benefits would be:
1. Better viewport representation
2. Scattering in Viewport is closer to the final result.

On a second level, there could also be a simplified (viewdependent) subdivision. Something lighter than the phoenix ocean tool. I really like the convenience of the Unreal Terrain Tool and wonder why nothing similar is available for 3ds Max.

If there is a good workaround I am all ears . Currently I use a hidden plane for scattering and a second plane for surface details. Or I use a regular displacement underneath and turn it off during rendertimes (but that does not work for scattering).

Thanks, Peter
xoio

[^Lele^]

fPro has a tool to simulate the perfect displaced mesh for scattering, without actually creating the triangles.
The thing is that to display it in a viewport, you need the triangles.
So, the "off in render" max displacement approach is the commonly used one: at least one controls the level of detail in viewport better.
Using automated, not "perfect" modes invariably leads to precision issues (trees on a road, etc.), hence hte manual approach is preferred.
If the fPro representation approach would work for you, then perhaps it could perhaps be added to our own scatter tool.

Displacement in v-ray has various modes, but by default the edge lenght is expressed in pixels, and that ofc is view-related.
It automatically takes care of reducing displacement detail outside of the camera frustum, as well as filling in details that are smaller than the edge lenght via the equivalent of implicit normal mapping.
Were you referring to this, or something else entirely?
For viewports, Max's are *most definitely not* as capable as UE's.
There is geometric caching on GPU going on which would likely make max crawl to a halt should the geo dynamically adjust.

As an alternative, you could export the displaced terrain as proxy, lose the view-dependancy, but you can possibly use it as a more faithful preview in viewports and if you load the whole proxy (watch the RAM!), also for scattering.
You wouldn't want the full mesh preview active at all times, but it should be easy to bake a scatter to instances and turn the preview off or delete the proxy later.

[Dmerc]

Thank you for your consideration. Scattering is only one part of the issue. Mostly it is actually really about working flexibly - placing objects on terrains as faithfull as possible - using (Gaea) Heightmaps . And the "Off in render" Option is good in theory, but I continuously bump into cases where this is not recognized and results in double displacement (Using VrayGPU or Vantage) for example. My thought was why not combine this into one tool?

About the viewport subdivision - I am not a programmer - but that could be done in a simplified version or capped so the viewport performance does not suffer too drastically. But true, I forgot about the Forest Pack Option to reflect VrayDisplacement - that would be very handy in the chaos scatter, too!