finalRender vs. mental ray

[Tom Hatfield]

Yo Adam: your artistry page is 404.

Has anyone here had the opportunity to use finalRender Stage-1 for 3ds max 6?

In my experience thus far, fR1 is far superior to mental ray 3 in its implicit functions. It will be difficult for any renderer to top mental ray in raw versatility, since mr is essentially programmable from the ground up, but just talking straight out of the box, I would say fR1 beats mr3 in every way, with the exception of final gathering (which fR1 does not support).

Granted, I don't know the shader language for mr3, so I haven't used it raw, but I've used it in 3ds max 6, Maya 5, and Softimage XSI 2. I was very impressed when I first discovered mr3 in Softimage. (At that point, max 4 had a connector to mr2, but mr2 was pretty much crap, unless you wanted to spend six weeks rendering a single frame.) For the longest time, I was hoping it would eventually be integrated into 3ds max (my software of choice — I don't know Maya yet), and finally it was.

I'd previously used fR Stage-0 when it was a prototype for max 4. It was nice — particularly since it was extremely difficult to find a good raytracer for max — but it didn't hold a candle to mr3. Stage-1 was released for max 5, and I still hadn't heard anything about it. (I stopped paying attention to the plug-in scene at this point because max 5 came with a tasty new feature: the advanced lighting engine.)

Just the other day — it may have been yesterday, in fact — I was digging around the newsgroups, asking people if they knew of a material plug-in that could render self-shadowing bump maps. Nobody did. A gentlemen pointed me in the direction of finalRender, which he said supports shadowed bumps. I immediately checked it out.

Well, yes, finalRender does support shadowed bumps — that is, the bump maps can displace raytraced shadows. The maps are not self-shadowing as I'd hoped. But then I made another startling discovery while perusing the documentation: finalRender also supports something called Micro Triangle Displacement (MDT), which is a vastly improved, on-the-fly form of displacement approximation.

I'm sorry if this technical jargon confuses some of you. As you may have guessed, this post is meant for 3D modellers.

MDT is a type of displacement, which means it builds added geometry to rough out the surface of your models. Because it produces extraneous geometry — and it does so on-the-fly, which I'll get to in a minute — the geometry is inherently self-shadowing, thus taking care of my bump map problem. Not only that, but it also reacts to local and neighborhood photon tracing (caustics and GI) and shadows cast by other objects.

And the rendering is fast if you tweak the detail settings. I managed to render (640x480) a fully detailed chipped sphere in about two seconds — complete with self-shadowing and all. (The GI rendition took much longer, of course, but looked equally better.) MDT creates extraneous geometry per-bucket, while the scene is being rendered — thus vastly reducing the amount of memory required to cache the scene. I've seen nothing in mental ray 3 that can do this.

As I continued to peruse the documentation, I dug up all sorts of neat things like volumetric caustics (this has been a hallmark of finalRender since its beta days), HyperGI (a hybrid GI-radiosity solver) for scenes with animated diffuse lighting, object ligths (actually, LumaObject, which has been integrated into Stage-1), a material that simulates genuine refractance (like you see when you turn a CD in the light) — I can't even remember it all.

To my knowledge, the only features mr3 supports (without writing your own shaders) are photon tracing and camera distortions — neither of which can compare to the options provided with finalRender Stage-1 right out of the box.

I don't particularly care if anyone disagrees with me on this one — you'd have to be crazy anyway — but I am interested in hearing what kind of experiences you graphics people have had with renderers. I understand cows is intimate with XSI and mr3 (when he uses it). I also know there are a great many people who use POVRay because they can't afford anything better. (Neither can I; I have to get by with limited demos.)

Well, I just wanted to get that out. I'm planning to use fR1 to do some graphics for a future DM clone project. I mentioned something about that last year, before real-life took hold. Anyway, I've got a summer to burn now.

Oh, hey, I also discovered DarkTree 2.5 the other day. Anybody else use that? It is so bad ass, it makes me want to cry.

[Tom Hatfield]

For the CD analogy, I should have said something intelligent like prismatic planar refraction, but I was high on fR fumes at the time.

[Tom Hatfield]

I was grossly mistaken — mr3 does in fact support MTD in its own form. My abject apologies. Strike one up for mental ray!

Also, I figured out how to do caustics in mr3. It's actually easier than finalRender because you don't have to configure your lights, but on the other hand, fR1's caustics look much better without any tweaking, and they do seem to render substantially faster. I haven't tested mr3 with DarkTree procedural displacement maps yet.

[cowsmanaut]

if you want good results at good speed with mental ray you need to make use of it's BSP settings and adjust things bu shutting down what you don't need etc. you can get some speedy results if you spend a little time. Mental ray has been left open for programming. Since you can run mental ray from CMD. I've seen som really fast results for things like GI and Caustics with even things like hair and particles and also volumetrics in a scene. just gotta know what you are doing.

You see there is a price for these open ended programs.. you get more power from them but you need to work a little harder to learn them to get what you want.

moo

[Tom Hatfield]

Yes, that's why it's nice to have such things as finalRender and Brazil.

As it turns out, mr does not support Simbiont (DarkTree) maps. Fortunately, DarkTree is able to render maps to a bitmap. It's not a perfect solution (you lost the advantage of procedural textures), but it produces good results.

I've developed a preference for mr3's displacement mapping. It's faster and easier to use than fR1, though the results general don't look as good as fR1's MTD. I used mr3 to render the scene posted at the DM&CSB Enc forum.

There is a strange bug in MTD that causes objects to disappear if the settings aren't just right. It's becoming a nuisance since I've started using displacement mapping in all of my scenes. I would like to move back to fR because it has much better lighting, but I'll have to resolve this MTD problem first.

[Tom Hatfield]

I've had a change in heart regarding mental ray. Contrary to my belief, mr3 displacement does in fact look much better than fR1 MTD. As it turns out, MTD utilizes a combination of displacement and bump mapping, and while the final result looks good from a distance, it has two problems: a) the geometry is not tesselated properly up close, and b) it does not cast proper shadows. (MTD also tends to produce cracks between triangles.)

Add to that the fact that I've learned how to use area lights in mental ray, and my final decision has become painfully obvious. I do appreciate the fact that fR1 supports DarkTree materials, and it does have a wide variety of specialized material types. In addition, fR1 makes better compromises between speed and quality when it comes to lighting — that is, you don't have to tweak it so much.

I'll be sticking with mr3 for the time being. I just need to figure out how to make the most of these DarkTree materials. So much for modular compatibility. It's annoying having to render them out to bitmaps, and the fact that they don't tile afterward is extremely bothersome.

[Gambit37]

??????????? It's all a foreign language to me!

[cowsmanaut]

Well, I've only had to utilise Mental ray in XSI mainly and to a smaller degree in Maya. However, Displacement can get rather ugly if you've not set the geometry aproximation to a decent enough level. Displacement converts to geometry at rendertime so it's likley more to do with setting fed to mental ray via the program.. I would imagine anyway. It's on a per object basis rather than a purely global setting.

Gambit, this is all terminology for 3D rendering using a renderer called Mental Ray. It's regarded as one of the top renderers in the world according compani surveys. Renderman Is top of the list and is created by pixar. However their release version is usually 1-2 versions behind the one they are currently using.. for reasons of competative market. You obviously don't want competitors with the same edge you have.

Anyway, if you're really interested.. you can feel free to ask questions. I'm open to information sharing and I'm sure Tom will supply what he's garnered from fiddling with this that and the other thing. He's got a great deal of knowledge in Max. I'm more Maya and XSI based.

moo

[Tom Hatfield]

Well, there is a third-party plugin that lets you render DarkTree materials with mental ray, but it's basically crap. Aside from being very annoying to use — you must specify the entire path for each DarkTree shader you want to use, and there is no "Browse" button — the displacement is tesselated prior to rendering, meaning it does not process on-the-fly like it should. I was very disappointed.

I was prepared to learn Maya for the sake of building UT2004 mods, but it hasn't been a high priority for me. Maya is incredibly similar to max — you could even go so far as to say Maya is 3ds max with better modeling tools (and a better default renderer).

By the way, there is no DarkTree plugin for Maya, but there is one for Renderman.

mr displacement in max is global, rather than per-object. For finalRender it's both global and per-object — you can choose which you want to use on a per-object basis. (This is one advantage fR1 has over mr3 in max.) On the other hand, mr3 displacement is insanely fast compared to fR1. I've been running detail tests, and mr3 wins out every single time.

finalRender is just as tightly integrated into max as mr3, and it allows for more customization. It's just that damned displacement mapping! I wish it were better.

I also discovered something very disappointing regarding DarkTree bump shaders. They do not generate grayscale bump maps; they generate normal maps. I'll have to check the documentation and see if there's a workaround for this, as max has no use for normal maps except with the DX9 material shaders (which I don't use).[/i]

Yes, I am very open to discussion. Knowledge is power. By the way cows, when you mentioned you had a friend who was going to school full-time for a programming degree, were you talking about me?

[cowsmanaut]

no I don't think so. Not sure what thread that was in. However, it could have been one of two people. Friend of mine named Robin.. or Alandale who is now working away at his masters?

anyway..

this is something that may interest you:

"TIWdtemental is a series of mental ray shaders that provide an interface to the procedural texture trees created with DarkTree 2, a sophisticated stand-alone procedural shader authoring tool for computer games, TV and film production. By simply giving a DarkTree texture file as an input parameter to one of the shaders, the texture is rendered without having to generate bitmaps first.

TIWdtemental can be used with any 3D application for Windows that uses mental ray as a rendering engine and allows custom mental ray shaders. It has been tested with mental ray 2.1x, 3.0x, 3.1x under Windows 2000 Pro. It has also been tested within Maya 4.5 and the mental ray for Maya 1.5 plugin. "


http://www.creative-3d.net/newsviewer.cfm?NewsID=641

moo

[Guest]

That's the plugin I was talking about. It's total crap. Thanks anyway.

[Tom Hatfield]

Sorry, that was me.