Cheetah3D 7.3 Beta 1

AndyThirtover said:

To be able to add a bake-texture tag, they needed to be:

'made editable'

Here's a before and after speed test. Will introduce some more lights to test further.

Regards


Andy

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What renderer are you using?

uncle808us said:

Should you also disable the Camera light?

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Yes, another important point, mesh lights are not considered by the "auto" setting of the camera light, so it must be switched off when there are only mesh lights in the scene.

misoversaturated said:

Also when using it with those free textures and then changing back to the old material node with the same textures (abandoning the whole specular & roughness stuff) I do not see much difference.

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There's very little a PBR shader can do that the material shader can't, but PBR shaders map really well into game development work flows (e.g. Unity replaced its dozens and dozens of shaders with a single "standard" PBR shader that does almost everything they all did more efficiently and simply) and even, I believe high end pre-rendered workflows.

In theory, Martin could implement a PBR OpenGL shader in the Editor view and we could get very nice editor previews. Similarly, Martin could tweak the FBX workflow (I believe) and get very nice throughput to Unity.

The screen capture below is from Unity's game preview window (real time, >60fps) with three standard shaders (the glass helmet, the weasel, and the brown speckled landscape). Note the soft shadows with light transmission through the helmet.

AndyThirtover said:

I think there is something else I'm missing.

It nearly worked this time:

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The problem with baked lighting is that it's only going to work well for bits of things which don't get varied lighting. So this mostly means static scenes. Baking the scene is going to take time and be fiddly, then you're going to need to change the scene to use the rendered textures, and now you're stuck with compromises (e.g. lack of procedural "infinite detail"). I don't really see the point. At best you're trading YOUR time (which is valuable) for the COMPUTER's time (which is cheap), at worst you're wasting time and getting inferior results.

What studios do instead is bake backgrounds and render foregrounds separately, but only if they can get away with it. (Usually a bunch of cheating is involved, e.g. look at the first "Mother Knows Best" scene in Tangled where they drop the background lighting to nearly nothing and then drop out the background altogether.)

Baking was originally introduced as a request from game developers, like me, who wanted to prepare stuff for game engines back when this was a big deal for performance. Today, realtime shadows are "almost free" with modern GPUs and in any event Unity (among others) has a very impressive built-in lightmap baking system.

BTW fantastic release Martin. Great to see caustics back — my enthusiasm for 7.x is renewed. Who knows I may finish revising my book…

Specular Long Tail Reflection

podperson said:

There's very little a PBR shader can do that the material shader can't

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Thanks for confirming my suspicion :smile:

But at least, given a little roughness, specular Highlights are rendered much nicer now (right side) compared to the metal shader (left side).





EDIT:
Oops, there is a shading artifact on the cube top!
I used the bevel from the cube properties, using a subdivision modifier shows an even surface.

I think there's a bug in the bevel proberty.
The render is from beveled cubes with a skylight (softness=1).

There's very little a PBR shader can do that the material shader can't, but PBR shaders map really well into game development work flows

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True, but that with the game development is a big advantage. Another one is the way Martin put it in. With the disney pbr Cheetah is just plain more compatible. The biggest, in my opinion, is just that there's a world of pbrs around, quiet a lot for free, which makes it easy to use prefabricated materials that can be tweaked to our needs. To create some of this stuff from scratch can be very time consuming.

I would have preferred, though, the possibility to use normals (real render geometry) and bumps at the same time.

And probably pbr is the better metal shader in falcon, too.

Just to expand what others are saying. PBR materials are meant to be transferable, compatible, consistent etc., in and out of C3D and other apps using it - and depending on your needs, that is highly desirable!
Aside from online pbr texture sets, 3D painting apps like substance painter and 3D coat export pbr textures. Materials appearing the same in C3D as they did in the painting application makes using the apps together an exciting option.

—shift studio.

Edit:
Ups, somehow mixed substance with substance painter. That really could be used in tandem with Cheetah and isn't as expensive as I had remembered.

3d coat on the other hand offers a 99 $-amateur version which is very restrictred in use (no commercial license, 2048 px textures). But the pro version is at least payable (379 $).

Substance Painter is just a PBR painter and a resource hog. 3D-Coat for it's actually quite low price offers you sculpting, retopology and PBR painting.

Shift Studio said:

PBR materials are meant to be transferable, compatible, consistent etc., in and out of C3D and other apps using it

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Thanks Shift for driving home the compatibility point.
I know the PBR option from Blender and never used it there because I couldn't see any advantage -
but now I realize that when I want to export a Cheetah scene for Cycles rendering with volumetrics, I can texture it right here and probably have comparable results over there - as you say, highly desirable :smile:

Amazing release Martin! And thanks so much for implementing glTF support (still looking forward to being able to export physics sims through FBX aka: https://www.cheetah3d.com/forum/showpost.php?p=106682&postcount=10 ).
I am just now starting to experiment with the PBR shaders. One question: is it possible to have transparency with PBR shaders?

Also, interesting little thread on Blender Artists forum discussing primary use of PBR - which, as already pointed out, is not to make things look "more real" but for consistency across applications without having to constantly adjust lighting:
https://blenderartists.org/forum/showthread.php?404819-PBR-shader-s

Support for glTF / glb is really exciting. Should make it easier to transport assets created in Cheetah to Microsoft's Mixed Reality Viewer, which uses glb files based on a PBR workflow, and also supports animation when Martin implements that feature. I am currently looking over the various free Microsoft developer tools for converting files to their 3D applications. For anyone else interested below is one of the relevant pages:
https://docs.microsoft.com/en-us/wi...els-for-use-in-the-windows-mixed-reality-home

Hi Pegot

Transparency isn't part of Disney's Principal Shader. In a lot of apps you can combine the PBR-Shader with other channels and / or layers of other materials, but that means losing the compatibility. In Cheetah you can't. So you have to give the transparent parts of a mesh another material.

In Cheetah, I think, you get a bit more of realism out of the new shader. Of course that's not the main focus of implementing it in all those other apps.

misoversaturated said:

While playing with the reintroduced caustics I noticed an old problem:
Reflections of lights in glass bodies are not consistent.

When rendering a scene with a mesh light vs an area light, the mesh light gets reflected and the area light not.

I would understand if non physical lights like point or distant show no reflections, but an area light with visibility turned on should not render differently than a mesh light (assuming the rendering of emissive bodies being the realistic way).

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I've fixed that problem. The area light samples got clamped although you've turned of clamping. Thanks for the tip.

Bye
Martin

Hasdrubal said:

I would have preferred, though, the possibility to use normals (real render geometry) and bumps at the same time.

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I’m not familiar with the Disney shader model Martin cited. You can use both bump and normal maps with unity’s standard shader. (And Unity doesn’t have clearcoat channels.) I believe Unity’s shader model derived from Allegorithmic which has become something of a standard.

Martin said:

I've fixed that problem. The area light samples got clamped although you've turned off clamping.

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Thanks Martin!

Today it's two years of C3Dv7 public beta testing!
I've done extensive testing with refractive objects since and never got true reflections except from HDRIs or mesh lights and am very relieved that there is some progress now.

Implementing the PBR (physically based rendering) concept involves not only the render engine but also the materials and the lights.
With refractive caustics reintroduced, a new PBR shader and soon a realistic area light there is great progress now in all three areas :smile:

Falcon caustics are awesome

I've been testing the new old caustic capabilities of Falcon with a soft sunlight, varying the filter value.
The results are impressive, converging quickly at the default value of 0.1. In this setup the Clamp Sample value of 10 is too low for my taste, the caustic patterns get severely diminished so I disabled it.



With values lower than 0.1 the adaptive sampling reaches its limits and visible noise remains. Clamping helps a bit but compromises the appearance of the caustic pattern.
Now turning AS off helps of course but then the rendering is a matter of hours not minutes.

Therefore I'd like to make a request:
Can we please get adjustable adaptive sampling?
It's not only a caustic thing, blurred reflections especially in combination with DOF rendering also tend to be left noisy.
And for animations (aside special cases like refractions etc) I'd like to have the possibility to render faster with more noise left which will disappear when watching the movie.

Another nitpick:
The sunlight (turbidity 4, albedo 0.3, plane with no=default material) shows a heavy brownish tint like it were at sunset time and not 14:00.
That's way different than the sunlight's diffuse lighting color in C3Dv6 or other apps I know.
For a long time I neglected the sunlight because of its sharp shadows but now I'd like to use it but without more neutral coloring I'd have to adjust all material colors (and than the shadow areas get too blueish).
When setting turbidity to 10 the color tint seems just about right to me (caustics being too reddish), but then the shadows are almost gone:



Finally I tried to provoke a specular reflection of the sunlight by introducing a slight (0.01) refraction blur to the dielectric shader (this blur method works well with the metal shader) but then I got all blackness (ray depth all at 12)



Nitpicks aside those Falcon caustics are just plain gorgeous!
(render with no adaptive sampling, caustic filter at 0.025)

misoversaturated said:

Also the new PBR materials work well with caustics, the setup is super easy and the result looks just right:

View attachment 32635​

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Wow, that looks great!

Great stuff mis — and yes the skylight with soft shadows is amazing. It would be nice to have more control over its tint in general (e.g. simulate weather, alien skies, etc.)

As for glTF, I'm hoping we can soon have a clean workflow to threejs which would let me build 3d games using bindinator.