Character Animation.

[vance3d]

Thank you Richard for the explanation of how you go about mixing character animation in with gi. I was amazed that you were able to set aside so much time for rendering (up to an hour a frame). On most of the jobs I work on that kind of time is never available. I'm alway trying to get render times down below 5 minutes a frame. And most of the time by the time I get involved with a project the deadline and budget have already been established so there is no going back and saying "hey guys we really need a week to render this thing the right way"!

Zerofractal,

with regards to integrating the character with the background, this is where rendering with a matte ground plane that has shadows turned on that effect alpha and compositing comes into play.

when you comp your character over your background, the black from the character rendering that has alpha information for the shadow will cause the darkening of your background layer.

V miller

[richard_rosenman]

Hey Vlad, that's a pretty interesting concept - it hadn't occured to me. I'll give it a try next time.

zerofractal:

I used to do a lot of my rendering many, MANY years ago with Mental Ray with Soft 3.x and back then, you had to produce a shadow the hard way - through difference passes. I guess I haven't wanted to change because I still use this method and it always produces the best shadow for me.

For those of you who don't know about deriving shadows through difference passes, this is how it works.

Render you scene with all white materials, and the object (character) casting the shadow, as a 'not visible to camera' object so it will still cast the shadow but not be rendered.

Then hide the character and render the same scene. This time the scene will be rendered without any shadows.

Then you bring the two layers into Photoshop or After Effects or any compositing software and you difference one from the other. Since everything is the same in both renders EXCEPT the shadow, the shadow will be the only thing remaining.

I find this system will give you a shadow in almost any lighting situation and you can even use it to derive GI shadow! It's a bit of a pain because it means rendering multiple passess, but well worth the result.

-Richard

[richard_rosenman]

Hey Dave.

Well, as I think you are quite farmiliar with production work, you know you can certainly build up a large number of layers for a given scene. As a result, file organization is imperative - as a matter of fact it is almost a full time job for our sys-admin.

Basically, when we produce a job, we have a working directory with the name of the client. Within this directory, we usually split it up into Max Files, Reference, Textures, Comps, etc. On another drive, we have the same client name under a "Renders" folder. Here we have every scene numbered out ie. SC10, SC20, SC30, etc. Within each of these scenes we have folders with dates on thim. ie. Jan 4, Jan 5, etc. This is where we put test renders from every night. (We always send out test renders every evening.)

Finally, within these scene folders (SC10, SC20) there will be one folder called final. In this folder there will be a number of directories labeled "Character pass, Shadow Pass, Highlight Pass, GI Pass, Volumtric Pass, and whatever else will be needed. This is very convenient for our compositor because he knows exactly where to find anything and everything.

Our max work files for every scene start off being sc10_01.max and usually end up at somewhere around 100 by the end of the job. YOU MUST NEVER DELETE ANY WORK FILES. This is the most important rule of production. You have absolutely no idea when a client may decide that he liked the test you did last week better than the last one you showed him!

Vince:

The rendering time issue varies greatly from studio to studio. I think I once heard PIXAR attributes a maximum of 1 hour of rendering time per frame. However, bear in mind they are using state of the art render machines and this could only be a rumour.

We have a 20 machine renderfarm and on top of that another 10 workstations on which the artists work on. That gives us a total of roughly 30 rendering computers a night. If we allow 1 hour per computer per frame, this means they can spit out 30 frames an hour which means on a night (from 6pm to 10am) they can spit out roughly 480 frames in that 16 hour period. That equates to 16 seconds of footage per evening. Since most commercials run about 15 seconds or 30 seconds, we can pretty much get the job rendered in a day or two. And like I said before, 1 hour is usually the maximum, it is more often than not only around 30 mins/frame. Had we not a renderfarm, I couldn't afford more than 10 mins/frame.

On our short film we did encounter a sequence with glossy relfections, GI and motion blur which brought the computers down to halt averaging 6 hours/frame! We had no choice but to let it run it's course and so we did.


Because a commercial job will have a schedule of about 1-2 months production time, I allow for 1 week of lighting and 1 week of rendering. This is more often than not a good amount of time.

Man, I really should properly write this down on my site for you guys...

-Richard

[Psy]

you should put a Q&A section at the bottom when you do, and include all the questions and answers posted so far, so that others can glean some knowledge from that as well.

Thank you for the write-up as it stands right now, gave me a real incentive to sit down and try it out.

[thumpa]

Wow!

Richard Rosenman - you rock!

Thanks for all that info Your work is fantastic, btw!

[Da_elf]

they might be exadurating to make it seem like some sort of magical thing. but on pixars website under the how we do it section they say between 6 hours and as much as 90 hours on some frames

[zerofractal]

Richard. you're the man!

[nildoe]

Richard dude!!!

Thats Exactly what i always wanted to know...VERY, VERY VERY VERY VERY THANKS ALOT!!!!!

Wow...alot is much more clear in my head now!

Nil

[OmeN]

Incredible post thats got a HUGE ammount of information even to those of us that are used to compositing layers.
Richard I do hope you can either write this all down for your website or make a video tutorial of the method you use with a fairly simple scene. Maybe the extra hard stuff that can occur can be written down or seperated into mini video tutorials ?
Thats purely a wish tho mate !

Q:
I quite like the way you make your shadow pass, however wouldnt it be easier just to put the matte material onto the objects that require it and render the pass ?

vlado: That does seem like a good idea.

[richard_rosenman]

Yeah...I've been meaning to put this all up on one page. I'll try and do this soon and let you guys know...

-Richard

[tom schuelke]

Hi richard

We just have done a longer architectural animation.

in one scene we had to render a truck with a helicopter on top of it entering a big building.

Our solution was to render the whole shot , like you did with a backround pass with precalculated i-map, and in front the "chrachter" with single frame, using vrays mate shadow options for backroundgeometry.

This way we got a pass only showing the helicopter, but also the shadows of the helicopter on the backroundgeometry and one thing i found that was very nice, the mooving reflections of the backround geometry, correctly mooving on top of the helicopter.

so my question is, did you already tried out the mate shadow options of Vray, and if so, was it only speeeed that brought you to your solution ?

the vray mate object properties for me seem to be very good, much better than thoose of the standart max material of mate shadow.

Tom from Hamburg

www.lichtecht.de

[cocolas]

Hi Richard,

thanks much for the great info!!!...really good stuff....

I was wondering if you could expand a little on your use of AA in you animations...especially the rendering of the environment part......I do archviz animations...and I find very hard sometimes to keep the geometry from flickering when assembled as a video....even as an uncompressed avi. That tends to happen mostly with geometry that's further/far away from the camera......how do you keep that from flickering (btw, it's not a light/GI flickering...it's thin geometry - like window mulions..etc)...???

I usually use simple two-level at 1/3 or 1/4 w/ random checked....it seems to work most of the time better then adaptive or fixed.......

what are your thoughts/suggestions on this??

thanks again,

paul.

[richard_rosenman]

Hey tom;

No, I haven't tried the VRay matte option for shadows. I will, though, now that you have mentioned it. It is true that my method is the 'old school' method that will work with any 3D software, but is not necessarily the fastest approach.

Paul;

I don't have much experience with architectural rendering but I ALWAYS render my final production renders with adaptive 0,2. Sometimes, when I can afford the extra time and I want a cleaner image, I will push it to 1,2. But that seems to always be sufficient for me and never produces aa flickering/artifacting. It is important to be able to distinguish gi artifacting from aa artifacting as they can often look similar. Of course, if you have lots of fine geometry then, that's another issue:

http://www.chaoticdimension.com/foru...pic.php?t=6086

Hope this helps answers your questions.

-Richard

[cocolas]

thanks for the tips and link, richard!

really appreciate it.



paul.

[OmeN]

Richard, not meaning to "nag" you or anything but do you have a rough idea of when you might do the tutorialwrite up on this ?
As I said if writing the whole thing is a pain..you've always got us video tutorial hungry freaks here


Sorry matey.