Tuesday, March 31, 2009

setting up a scene: some tech tips

This post is mainly for Sindhu, who is doing work on her thesis this term and just handed in a 70mb maya file for review. I’ve noticed at the academy that a lot of students don’t have a good understanding of setting up a multiple camera shot, let alone a short film.

Referencing

I can’t underestimate the power of file referencing in maya. It allows you to continue refining your rigs and sets over the course of your shot and  immediately get to the essentials of storytelling – a great layout you can start animating with. I really feel that shot composition and layout are the first thing that needs to be dealt with. This includes large shadow shapes (see the storyboards for any Hitchcock movie…they deal with shadow groups as compositional elements from the start.

The real power of referencing is to have faster playback in maya. A fast playback speed is esssential to getting to the heart of your timing. Playblasting is, of course, the only true way to see your timing, but a fast rig in an environment without heavy texturing will let you get to your goals faster.

To reference,  set up your rig and set in seperate files with no keyframes on them, otherwise you won’t be able to key in maya.

In maya, go to file…reference and click on the little box. Prefix the nodes with something simple rather than the file name, otherwise your outliner and hypergraph will be impossible to navigate quickly.

The nice thing about being able to reference scenes is you can toggle the visibility off, which is nice for scenes with multiple characters and high res facial rigs.

The first thing I do when creating a set is to create a PROXY version of it. If it’s a building, I’ll make a cube to the same proportion, colored in a solid color with no texturing. I’ll swap the textured version back in for rendering or when it’s necessary to see a lighted version of the scene or to start rendering (a part of the process you can do later or in parallel to the animation process)

Having PROXY characters is useful, as you can start blocking out your scene before you’ve finished the facial rig. The trick with referencing and the main warning I’ll give you is to not remove nodes from your reference files, nor should you rename them, as maya finds the keys through the NODE NAMES.  Referenced files work well if you continue to add to them, but if you do something radical, like change your rigging, you will lose animation.

As a safety measure, I like to export my animation to a text file after it’s pretty well along, as the file sizes are small, and if anything goes wrong, it’s easy to recreate your scene quickly by referencing your files back in with the same prefix (or renaming the prefix in the reference window)

TIP: If you add a constraint to a referenced file, find your constraint node in the hypergraph (grab your constrained object, open the hypergraph, press F and follow the connection to it)..then UNPARENT THE CONSTRAINT. This will solve a lot of file crashing errors that sometimes come up (the boring reason is because it loads the constraint AFTER the rig is loaded.

TIP: Be careful of light linking to referenced file. That often causes crashes as well.

the Camera

So you want multiple cameras in your scene. Not a problem. I’ll give you 2 methods, the brute force system and the technical way. The brute force method is just moving your camera over at the starting point of your shot.  In the strictest sense, every camera cut is really a new shot, but if you’re doing a 10 second dialogue piece with a singe cut, you probably don’t want to seperate it out into 2 scenes and then composite them together. The technical solution is to use one of the genius melscripts often found on highend3d.com

The 2 I use the most are

shotview.mel and

zooShots.mel, part of Hamish Mackenzie’s incredibly useful script suite a macaronikazoo.com

Zooshots works like this. Create your scene with cameras. Create a new camera, define that as your master camera, then it slaves itself to your other static cameras and switches at the right point. I’ve worked on games where very long cutscenes had to be one incredibly long shot, and a tool like this is a lifesaver.

Let me know if this is clear…

4 comments:

TJ Phan said...

Great post--from referencing to proxies to shotView. I'll have to check at zooShots next chance I get.

Jason Fittipaldi said...

Great post Jeff! I've always heard a lot about the benefits of referencing for animating a shot.

I may get around to trying it out on some upcoming projects now :)

Sam said...
This comment has been removed by the author.
Samyuktha said...

Hi Jeff,

This is Sam from your class, last semester. I posted from a different account and deleted it.
I just wanted to say that this post is very helpful and explains a lot. Thank you!