Rendering Large amounts of Trees and Plants in Vray

Rendering V-Ray
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1

Hi there,

Im wanting to learn Vray for rhino to render grass and plants for large landscapes. The landscape intends to have up to thousands of plants, trees, and fur grass.

I am wondering if anyone can give advice on how to setup LOD or other ways to enable this to work? Perhaps, I can buy a plant pack, and lower the mesh resolution..

Any more experienced thoughts would be greatly appreciated.

-Jeremy

2

Hi @jdelavaulx

Vray is an awesome program. If you want a free alternative that works with rhino and has a huge library of free assets than you could try Epic games Twinmotion it has a direct link to Rhino.

Twinmotion has megascan libraries of trees and plants you will need an rtx video card but I think Vray is also hardware intense and also has hardware requirements. Twinmotion sets up lods automatically and now supports Nanite. You can also convert Megascans 3D assets and 3D plants to Nanite, as well as Sketchfab assets. Got an existing project that’s feeling a bit heavy and sluggish? Give Nanite a try and check out the difference.

https://www.twinmotion.com/en-US

RM

3

yeh you probably want to look at Twinmotion

4

Hi,

If I understand correctly you don’t have the vegetations assets already. In that case you can take a look at Chaos Cosmos. This is the Chaos asset library that comes with V-Ray for Rhino and is free to use. It has considerable vegetation assets set of ~2400 assets, and new assets are added frequently.
Cosmos assets are proxies - meaning their geometry and materials are represented a simplified way in the viewport but rendered in high fidelity manner. Typically you want low or medium polygon count in the viewport and high poly in the renderer.
V-Ray for Rhino can show 5 different representations of each asset in the viewport:

image
image420Ă—176 3.37 KB

so no matter how intensive your scene is you can always switch to “point” representation which does not put much load on the CPU if any.

Furthermore there is a several ways to scatter the assets unless you plan to place them manually. The Scatter modifier can generate millions of instances with variations for each asset, group and cluster them, or distribute along UV grid or texture… you get the idea. All of that is render-time and will not pollute your viewport with tons of geometry, only displaying subsets of the instances or represent them as points or bounding boxes

Furthermore in V-Ray for Grasshopper, that also comes with the Rhino plugin, you can have even finer-tuned scattering via the Scatter or Instancer nodes.

All of that renders on CPU or GPU, or both combined. You just need a CUDA-enabled graphics card. If RTX card is available, V-Ray will take advantage of it.

Another product would be Rhino Nature, which is scatterer only, that comes with vast asset library. It is supported by various renderer, including V-Ray

If you don’t already have them you can get a trial for both products and give them a try

5

Vray and other renderers generally use instancing, which they can translate from blocks in Rhino, to do massive quantities of foliage.

6

My advice to optimize this kind of situation would be:

  • Never use fur grass. Instead, use the Scatter command together with the grass patches available in Chaos Cosmos.
  • For the trees, I usually use the ones available in Chaos Cosmos (they’re low-poly), except for those visible in the foreground - in that case, I recommend using high-quality models from Maxtree or 3Dsky (they’re paid, but definitely worth it).
  • For trees that are very far away, I suggest using PNG backplates.

These suggestions work well when producing images with the camera set at eye level. If you’re creating aerial views, just follow the first two recommendations.

7

Really appreciate the words of wisdom :slight_smile:

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What would you suggest if one wanted to produce video fly-throughs where you render each frame whilst the camera is moving?

-Jeremy

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Grasshopper

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Hi a2rc, thanks so much for your advice.

  • What if the scene had like 80-90 thousand total plants; trees, shrubs, grasses etc., and someone wanted to produce both stills and a series of stills for video?
  • I could use chaos plants, proxies from Maxtree, 3Dsky, etc. but Not sure if this would be a viable workflow.
11

Thanks so much for all of this information Nikolay :slight_smile:

  • Do you know if there’s any way to use a black/white mask for scatter in vray for rhino? I think that this would be very useful for me.
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Hi RM, Thanks so much for your advice.

I am looking to do two things: 1. create standalone high quality renders, and 2. create video fly-throughs.
Both will be of large landscapes:

  • Up to maybe 100,000 plants (species of trees, shrubs, fescues),
  • Landscape topography meshes
  • Some 3d objects like fences, a few buildings, roads,
  • Perhaps animated assets such as people/cars or breeze affecting plants

I also need to have control over placement of assets. For example, where fescues/shrubs are; according to points in rhino, or perhaps a greyscale mask to control where grass shows.
It would also be ideal to be able to have blend materials which can themselves be controlled by greyscale masks as well.

I’ve been thinking about several ways forward for this endeavour, but not sure what is the best for the above requirements.

  • Vray seems versatile, has excellent quality, and acts as a direct extension on rhino. But for video fly-throughs requiring say 1350 frames for a 45s video at perhaps 5mins/frame, it might be a problem.
  • Enscape’s real-time rendering is quick, and might be good for video; whilst Vray might be used for stills.
  • Twinmotion seems powerful as an external standalone real time renderer.
  • Unreal engine seems quite a steep learning curve, but would be ideal for optimise renders for large projects.

Thoughts?

-Jeremy

13

I’d like to mention here that you have number of options with V-Ray here:

  1. Render on the cloud. V-Ray supports cloud rendering, so that many frames on a cloud-based render farm is not that slow to render, it is associated with extra cost, though.
  2. Batch render. There is a built-in batch renderer in V-Ray. You can render your video overnight
  3. Use denoiser. V-Ray comes with 2 kind of denoisers (3 if you have NVidia card) that can cut rendering time significantly
  4. Vantage or Envision. V-Ray can Live-link to Vantage or export a scene to Envision (Live Link coming soon too) which are both animation-enabled real-time solutions that can render your video fast. Mind that those are separate products, but eventually you will get exactly what you see in V-Ray. All the assets and materials are natively supported by these products.
14

Wow, thanks so much for this information.

I was thinking about render farms, and I know that there’s a lot to learn with regards to optimising the render workflow to minimise excess compute on unnecessary items.
I have a RTX3090
I will take a look at Vantage and Envision; and learn what they have to offer.
Vray does look very powerful and promising and versatile.

Do you know if there’s a way to have moving people, or moving trees with wind in Vray?

-Jeremy

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Chaos Cosmos library does support moving trees - blown by a wind, but those are moving only in Vantage. If you live-link or scene export your model to vantage you will get that wavy movement:

Simply look for the “animated” icon in chaos cosmos:

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Mind that those assets are not animated in Rhino - even if you render in “animation” mode.

Apart from that implemented Animated people in Chaos Cosmos and Vantage is currently in progress.

There is another Chaos product dedicated for for animated (rigged) people and vehicle assets - Anima

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Hi Nikolay, thanks again for your response.

I found a video render which I aspire to be able to emulate.

With your expertise, what can you determine from this, and does it look like it was created with realtime rendering, or physical, or does it show the look of a particular rendering suite?

Kindly,
Jeremy

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Hi @jdelavaulx
I think it’s a variety of programs along with compositing/editing of many animations, the terrain was 3d modeled using civil engineering programs before it even went to rendering.

Anyway I came across all these nice vray tutorials on Youtube and remembered your thread, since you’re going that route.
Animate Like a Pro with V-Ray for Rhino - YouTube

RM

18

As @3dsynergy pointed out there are plenty of products, including all that were quoted here that can produce this imagery. And it all boils down to the pros and cons that come with each solution.

In other words - the problem is neither modeling, assets nor production capabilities, this all is absolutely possible. What you need to concentrate on is clearly defining your requirements and match them against the offerings of each product and its ecosystem you’re considering.