volumes

VDB as displacement /  by Xuan Prada

The sphere is the surface that needs to be deformed by the presence of the cones. The surface can't be modified in any way, we need to stick to its topology and shape. We want to do this dynamically just using a displacement map but of course we don't want to sculpt the details by hand, as the animation might change at any time and we would have to re-sculpt again.

The cones are growing from frame 0 to 60 and moving around randomly.

I'm adding a for each connected piece and inside the loop adding an edit to increase the volume of the original cones a little bit.

Just select all in the group field, and set the transform space to local origin by connectivity, so each cone scales from it's own center.

Add a vdb from polygons, set it to distance VDB and add some resolution, it doesn't need to be super high.

Then I just cache the VDB sequence.

Create an attribute from volume to pass the Cd attribute from the vdb cache to the sphere.

To visualize it better you can just add a visualizer mapped to the attribute.

In shading, create an user data float and read the Cd attribute and connect it to the displacement.

If you are looking for the opposite effect, you can easily invert the displacement map.

Deep compositing /  by Xuan Prada

Hello patrons,

In this 2 hour video we are going to be talking about deep compositing workflows.

I will show you how to use deep compositing and why you should be using it for most of your shots.
I will explain the basics behind deep rendering and compositing techniques and also we'll go through all the deep tools available in Nuke while comping some simple shots. From volumes and atmospheric effects to solid assets.

Video and downloadable material will be included in the next posts.
All the information on my Patreon.

Thanks for your support!

Xuan.

Small dynamic clouds /  by Xuan Prada

Hello,

I don't think I will be able to publish a video this month, let's see, but in the meantime here you can download five caches of small dynamic clouds that I simulated in Houdini.
They are a 1000 frames simulation and should work pretty good to create vast cloudscapes.

They are .bgeo caches, feel free to convert them to .vdb if you want to use them in any other software.


The videos below are flipbooks of the animated clouds, not renders.

The downloadable link will be published in the next post.
This is free of charge for all tiers with downloadable resources.

Thanks,
Xuan.

Introduction to Redshift - little project /  by Xuan Prada

My Patreon series “Introduction to Redshift for VFX” is coming to an end. We have already discussed in depth the most basics features like global illumination and sampling. I shared with you my own “cheat sheets” to deal with GI and sampling. We also talked about Redshift lighting tools, built-in atmospheric effects, and cameras. In the third episode we talked about camera mapping, surface shaders, texturing, displacement maps from Mari and Zbrush, how to ingest Substance Painter textures and did a few surfacing exercises.
This should give you a pretty good base to start your projects in Houdini and Redshift, or whatever 3D app you want to use with Redshift.

The next couple of videos about this series are going to be dedicated to doing from scratch to finish a little project using Redshift. We are going to be able to cover more features of the render engine and also discover more broad techniques that hopefully you will find interesting. Let me explain to you what is all of this about.

We’ll be doing this simple shot below from start to finish, it is quite simple and graphic I know, but to get there I’m going to explain to you many things that you are going to be using quite a lot in visual effects shots, more than we actually end up using in the shot.

We are going to start by having a quick introduction to SpeedTree Cinema 8 to see how to create procedural trees. We will create from scratch a few trees that later will be used in Houdini. Once we have all the models ready, we will see how to deal with SpeedTree textures to use them in Redshift in an ACES pipeline.

These trees will be used in Houdini to create re-usable assets llibraries and later converted to Redshift proxies for memory efficiency and scattering, also to be easily picked up by lighting artists when working on shots.

With all these trees we will take a look at how to create procedural scattering systems in Houdini using Redshift proxies. We will create multiple configurations depending on our needs. We are also going to learn how to ingest Quixel Megascans assets, again preparing them to work with ACES and creating an additional asset for our library. We will also re-use the scatterers made for trees to scatter rocks and pebbles.

To scatter all of that will be used as a base Houdini’s height fields. For this particular shot, we are going a very simple ground made with height fields and Megascans, but I’m going to give you a pretty comprehensive introduction to height fields, way more than what you see in the final shot.

Once all the natural assets are created, we’ll be looking at the textures and look-dev of the character. Yes, there is a character in the shot, you don’t see much but hey, this is what happens in VFX all the time. You spend months working on something barely noticeable. We will look into speed texturing and how to use Substance Painter with Redshift.

suit.png

Now that we are dealing with characters, what if I show you how to “guerrilla” deal with motion capture? So you can grab some random motion capture from any source and apply it to your characters. Look at the clip below, nothing better than a character moving to see if the look actually works.

It looks better when moving, doesn’t it? There is no cloth simulation btw, it is a Redshift course, we are not going that far! Not yet.

Any environment work, of course, needs some kind of volumetrics. They create nice lighting effects, give a sense of scale, look good and make terrible render times. We need to know how to deal with different types of volumetrics in Redshift, so I’m going to show you how to create a couple of different atmospherics using Houdini’s volumes. Quite simple but effective.

Finally, we will combine everything together in a shot. I will show you how to organize everything properly using bundles and smart bundles to configure your render passes. We will take a look at how Redshift deals with AOVs, render settings, etc. Finally, we will put everything together in Nuke to output a nice render.

Just to summarize, this is what I’m planning to show you while working on this little project. My guess is that it will take me a couple of sessions to deliver all this video training.

  • Speed Tree introduction and tree creation

  • ACES texture conversion

  • ACES introduction in Houdini and Redshift

  • Creation of tree assets library in Houdini

  • Megascans ingestion

  • Character texturing and look-dev

  • Guerrilla techniques to apply mocap

  • Introduction to Houdini’s height fields

  • Redshift proxies

  • Scattering systems in Houdini

  • Volume creation in Houdini for atmospherics

  • Scene assembly

  • Redshift render settings

  • Compositing

  • Something that I probably forgot

All of this and much more training will be published on my Patreon. Please consider supporting me.

Thanks,
Xuan.

Rendering OpenVDB in Clarisse /  by Xuan Prada

Clarisse is perfectly capable of rendering volumes while maintaining it's flexible rendering options like instances or scatterers. In this particular example I'm going to render a very simple smoke simulation.

Start by creating and IBL setup. Clarisse allows you to do it with just one click.

Using a couple of matte and chrome spheres will help to establish the desired lighting situation.

To import the volume simulation just go to import -> volume.

Clarisse will show you a basic representation of the volume in the viewport. Always real time.

To improve the visual representation of the volume in viewport just click on Progressive Rendering. Lighting will also affect the volume in the viweport.

Volumes are treated pretty much like geometry in Clarisse. You can render volumes with standard shaders if you wish.

The ideal situation of course it would be using volume shaders for volume simulations.

In the material editor I'm about to use an utility -> extract property node to read any embedded property in the simulation. In this case I'm reading the temperature.

Finally I drive the temperature color with a gradient map.

If you get a lof of noise in your renders, don't forget to increase the volume sampling of your lighting sources.

Final render.