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Andyjaggy
01-03-2008, 11:54 AM
Just got a chance to play around with renderman.

Man.

Crazy super highrez displacement.

Maya default renderer: 250 seconds
Mental Ray: 35 seconds
Renderman: 5 seconds

Dang. I see why people use it now.

Mitja
01-03-2008, 12:43 PM
I heard a lot about this renderman, but what is it exactly? They use it at Pixar if I am not wrong, don't they...?

Titus
01-03-2008, 12:46 PM
I heard a lot about this renderman, but what is it exactly? They use it at Pixar if I am not wrong, don't they...?

RenderMan is a scene description specification defined by Pixar. RenderMan is also refered as a renderder developed by Pixar, but anyone can write a RenderMan compliant renderer.

http://en.wikipedia.org/wiki/RenderMan_Interface_Specification

Steamthrower
01-03-2008, 12:46 PM
Is there a wee renderer for Mac, is what I'd like to know.

Steamthrower
01-03-2008, 12:51 PM
Found this interesting quote on Wikipedia.


Every movie nominated for a Visual Effects Oscar in the last 10 years relied on Pixar's PhotoRealistic RenderMan (PRMan).[citation needed] In addition, PRMan has won an Oscar from the Academy of Motion Picture Arts and Sciences.

Titus
01-03-2008, 12:54 PM
Is there a wee renderer for Mac, is what I'd like to know.

Yes:

http://www.3delight.com

http://www.aqsis.org

http://www.cs.utexas.edu/~okan/Pixie/pixie.htm

http://jrman.sourceforge.net/

Mitja
01-03-2008, 12:58 PM
And 3delight is for free (first license), but it is for Maya.
Titus, it seems you know your stuff about Renderman...how is 3delight? And the others as well...

Steamthrower
01-03-2008, 01:02 PM
And 3delight is for free (first license), but it is for Maya.
Renderman for lightwave = utopia ?

Just about.

Surely there's got to be a Renderman exporter for Lightwave somewhere. Surely. I'd pay for it if there was! Got to Google for Renderwave or Lightman...

Steamthrower
01-03-2008, 01:06 PM
Well what do you know, there's really one. From our very own Titus, I didn't even see it in his signature (I Googled it).

http://www.garagepost.tv/renderman.htm

Mitja
01-03-2008, 01:06 PM
Look at titus signature, or whatever it is called! The thing is becoming interesting!

Steamthrower
01-03-2008, 01:08 PM
Look at titus signature, or whatever it is called! The thing is becoming interesting!

I hadn't even considered Renderman back when I was searching for alternative LW renderers. I have a long animation project coming up and using these renderers might very well assist me in it.

I'm such a dolt.

Mitja
01-03-2008, 01:11 PM
I have to give it a look, I really have!!!

Mitja
01-04-2008, 05:57 AM
I looked a little bit at the 3delight manual... and I'm quite confused... it's all programming or something...There's nothing that I hate more than programming!!
So if anyone will to try it, please tell me how it works. And if anyone had tryied another one, share as well, please!
This Renderman is so "fascinating", a kinda misterious thing to me.

Andyjaggy
01-04-2008, 08:26 AM
There are many flavors of renderman. Some are pretty much a programming language, others like the one I was playing around with are a render plugin for Maya and work pretty much like you would use MR. I'm not an expert though, best talk to Titus about it.

Cageman
01-04-2008, 09:16 PM
Renderman kicks some serious buts. We compared it with MR on some of the heaviest shots we did in New York Trailer (World in Conflict) and it was just... kick *ss. One shot in particluar was kind of unreal for us. We had to split that shot up in many layers in order to render it with MR, each layer taking between 7-14 minutes with motionblur. Renderman...well, first of all, we didn't have to split it into layers, secondly, it rendered a frame in 3-4 minutes with motionblur. This was with Renderman for Maya (not the high-end standalone product).

Simply Amazing!

Titus
01-04-2008, 09:53 PM
Dan Maas created this animation using LW and RenderMan. The Mars surface is just a plane with a huge displace map (he had information directly from NASA).

http://www.maasdigital.com/

Just until the creation of RenderMan for Maya (RfM) using RenderMan was only for mad scientists and programmers :). I've stalled developement of Light-R mainly because I don't have the need to use RenderMan since the appearance of F-prime (my projects are simple commercials right now), you are welcome to play with it, though. A couple of programmers from big studios have asked for the source code of mi plugin, maybe I can open source it but there's a lot of work to do for a complete version, specially with the new features of LW 8 and 9. It took me some time to translate/reverse engineer some basic surfaces to RenderMan shaders, I can't imagine how much will take to replicate all the node shaders. In another side I'm thrilled to know how nice the new CC subs are translated to RenderMan CCs.

Some thougths:

RenderMan was created having in mind movie projects, one example is you can't render frame fields, but you have the option to use the most beautiful motion blur in the industry to avoid flickering.

Do you want instances? pffff... easy, just add nulls to your scene.

Many file formats are based on the RIB format, so once a LW converter is done, it could be trivial to have these programs working also.

LW uses polygons (everybody here knows this already), but this is the less efficient primitive in RenderMan. CC was a pain in the but to texture in RM at least a few years ago.

Pixar used raytracing in their movies just recently (in their first 4 movies they used raytracing only in one scene), radiosity is even more rare because everything is faked using shaders.

Mitja
01-05-2008, 03:56 AM
Cageman - Renderman kicks some serious buts. We compared it with MR on some of the heaviest shots we did in New York Trailer (World in Conflict) and it was just... kick *ss. One shot in particluar was kind of unreal for us. We had to split that shot up in many layers in order to render it with MR, each layer taking between 7-14 minutes with motionblur. Renderman...well, first of all, we didn't have to split it into layers, secondly, it rendered a frame in 3-4 minutes with motionblur. This was with Renderman for Maya (not the high-end standalone product).

Simply Amazing!
I gave a look at the trailer and I like it, simply awesome. Those shots took 4 mins per frame...hmm, it makes me wonder what kind of huge scene must be one that renders in 70 hours, like some of finding nemo or monsters and co...
LW is a "couple" of years behind, I think...


titus - there's a lot of work to do for a complete version, specially with the new features of LW 8 and 9
What features are supported so far? If I export a scene with your plugin, and try to render with a renderman compliant renderer, what twakings would I have to do to make it look like the original?


LW uses polygons (everybody here knows this already), but this is the less efficient primitive in RenderMan
:confused: Is there something more efficient than a triangle?:D

cresshead
01-05-2008, 04:33 AM
:confused: Is there something more efficient than a triangle?:D

yup...implicit surfaces, nurbs, splines, patches, displacements...and having an app that can use instancing and bucket render technonolgy and also lazy loading of data.

even polys can be better handled if they can be controlled in the renderer/scene depending on their distance and therefore complexity can be adjusted/reduced.

and also render to layers...maya has a robust render to layer capability and so does xsi i believe...3dsmax can output to a combustion workspace also which is really handy if you adjust your scene in post as nr all productions do thesedays.

Cageman
01-05-2008, 04:47 AM
I gave a look at the trailer and I like it, simply awesome. Those shots took 4 mins per frame...hmm, it makes me wonder what kind of huge scene must be one that renders in 70 hours, like some of finding nemo or monsters and co...
LW is a "couple" of years behind, I think...

We didn't render those with Renderman, they were rendered with MR. Aftwerwards we got to evaluate Renderman for Maya and we did some comparing tests. The smoke and all effects were always rendered in separate layers (acutally, all smoke was rendered with Maya Hardware using a custom-made 6-pointlight smokeshader, developed by our Effects-Lead, Anders Egleus). I'm just talking about raw polygonrendering comparsion.

You should know that MR is utterly crap at rendering motionblur; according to some tests I've done in LW, I would place LW somewhere between MR and Renderman when it comes to MBlur quality and the time it takes for a render. Not bad at all considering that a single license (both MR and PRman) costs more than 1 LW license with 999 rendernodes. ;)

With that said, LW needs more work on the renderer, a rehaul of all lights with added features and shaders that can reflect lightsources within the specular value (not using any reflection that is).

Anyhow, Renderman is probably the best renderer for VFX, and will continue to hold that crown for many years to come.

Mitja
01-05-2008, 05:26 AM
...implicit surfaces, nurbs, splines, patches, displacements...

Implicit surfaces: surfaces which are contours (isosurfaces) through some scalar field in 3D? Like metaballs?

Nurbs and patches: can I say they are a way to create polygons, to place them in the space in a certain way to obtain a soft shape? But this shape is made of polygons, isn't it? If one is particularly talented, could create this handly, without nurbs and patches.
Displacement: it moves polygons from their "rest" position (let me say this way).

It's bit confusing... after all, everything is based on polygons... I would just understand the concept.

Ember
01-05-2008, 07:34 AM
Nurbs and patches: can I say they are a way to create polygons, to place them in the space in a certain way to obtain a soft shape? But this shape is made of polygons, isn't it? If one is particularly talented, could create this handly, without nurbs and patches.


In OpenGL preview: yes. In renderer: not necessarily. Many renderers do indeed tesselate NURBS-surfaces into polygons before rendering but there are renderers out there which don't have to do this. Realsoft3d is one of those and I'd be suprised if some of the renderman compilant renderers couldn't do the same.

Titus
01-05-2008, 10:53 AM
Nurbs and patches: can I say they are a way to create polygons, to place them in the space in a certain way to obtain a soft shape? But this shape is made of polygons, isn't it? If one is particularly talented, could create this handly, without nurbs and patches.
Displacement: it moves polygons from their "rest" position (let me say this way).


RenderMan converts everything to micropolygons (MP) in a very efficient way. If you have a NURBS object the number of final MP will be based on variables like distance to camera and your selected option of MP per pixel, also called shading rate. This is more efficient than converting a NURBS surface into a fixed number of polygons like most programs do, the same applies to subds.

About displacement: it's a common trick to use disp/normal displacement of very simple objetcs in RenderMan. Do you remember Animatrix: The last flight of the Osiris? all the flying machines were heavy displaced cilinders.

Mitja
01-05-2008, 12:12 PM
Aha, I see, this make sense... So, if I understand, it's possible to make a head simply displacing a sphere. No modeling reqiured? (theoretically)
And what makes RM so fast? These tricks?

btw, I haven't seen Animatrix yet, maybe some day... Is it some kind of a matrix sequel, or I've read wrong (after a brief search) ?

gatz
01-05-2008, 01:09 PM
Animatrix was a collection of anime inspired shorts produced by the Wachowski Bros. and some leading anime studios. The Flight is a prologue to Revolutions and is done in the style of the Final Fantasy movie. Second Renaissance is cel animated and probably my favorite Matrix film besides the first film itself.

On the Renderman subject: Don't all shaders, nodes etc need to be rewritten as Renderman shaders? Or is this handled by the exporter?

rg

Andyjaggy
01-05-2008, 04:48 PM
We didn't render those with Renderman, they were rendered with MR. Aftwerwards we got to evaluate Renderman for Maya and we did some comparing tests. The smoke and all effects were always rendered in separate layers (acutally, all smoke was rendered with Maya Hardware using a custom-made 6-pointlight smokeshader, developed by our Effects-Lead, Anders Egleus). I'm just talking about raw polygonrendering comparsion.

You should know that MR is utterly crap at rendering motionblur; according to some tests I've done in LW, I would place LW somewhere between MR and Renderman when it comes to MBlur quality and the time it takes for a render. Not bad at all considering that a single license (both MR and PRman) costs more than 1 LW license with 999 rendernodes. ;)

With that said, LW needs more work on the renderer, a rehaul of all lights with added features and shaders that can reflect lightsources within the specular value (not using any reflection that is).

Anyhow, Renderman is probably the best renderer for VFX, and will continue to hold that crown for many years to come.

Yes at 700 bucks a node for renderman for maya, it adds up quickly. If you've got the cash though it's the way to go.