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Enter Jos Stam, a scientist working on a dynamics system called "nCloth", which ships with the high-end version of Maya, from version 8 ? more or less ? onwards. Ncloth is a wonderful idea, implemented by a really smart guy. In other words, not only the idea is elegant, the software actually is elegant and works.
What you do is build your objects and place them in your scene more or less in the usual way you would without dynamics. You make certain considerations for things to move and accelerate until they enter the frame at the right speed, etc., as you normally would when planning the shot. Of course, the honeymoon usually ends there, as now you face the delights of building a set of dynamics, constrains and springs ?or however your software of choice calls the magical act of giving things heft inside computerdom. Or you can use something like Ncloth. THEN you simply describe the relationships between the different elements and what part do they play in the shot. That's it. Ncloth does the grunt work, and amazingly efficiently. Check out this You-tube animation:
First, then, lets break down the SPLAT into its constituting elements. A minimal analysis of my dream falling hamburger reveals several of these, not counting liquids like ketchup and mustard, which I have decided I'll solve with particle systems and traditional dynamics simulation, both of which are found in most decent 3D packages and in some very cool Best-Of-Breed apps like Particle Illussion or mis colegas from Spain, the team RealFlow, who have received this year's Oscar for their wet code.
Some objects are lighter, others heavier. I try to classify that on the left side, with the lettuce leaf the lightest and the meat patty the heaviest. Some objects, on the other hand, are more rigid than others, and finally some are bouncy while others are not, thus the combined notations to the right of the elements.
But the crucial thing here is that objects will "flex" only where there are natural divisions, like facets or isoparms, for the physics program to act, so the first thing to attend to is to construct everything so it acts the way I need. Needless to say, other oses, other hamburgers, so to speak.
SHOW ME THE MONEY
Now for the cold equations. I have this notion that all the objects are somewhat radial in their symmetry, that means that I can build their basic shapes very economically with a bunch of cleverly placed curves, and then let the program do the lifting.
First, the curves, on an orthographic or flat view from the front. The black line they touch is the vertical axis.
Now, all is in the wrist. First: Create surfaces by rotating the curves around the Y axis:
Last but not least, the lettuce. At first I design something like a neck ruffle by tweaking a curve, duplicating it to the center so I have two matching curves...
and "lofting" or "skinning" those:
but that does not look sexy as it falls, so I build the thing as a CONE and reduce the Y scale until it is almost flat. And that works, fluttering nicely as it descends.
The next steps involve defining the way these objects look. After tweaking these basic models into something more organic, which entails massaging the shapes until they are not quite symmetrical and perfect by pulling control vertices and sculpting with the Artisan brushes, another Maya trick that lets you play with putty a bit and then we're out to colors and textures, creating what is known as "shaders" or little definitions for light and color behaviors.
These models are being designed for comedy and they have to be finished enough to be fun, but not more, under penalty of running higher budgets. So next time we'll concentrate on achieving a set of convincing qualities for our hamburguer, quickly but nicely and without a heavy computational load.
Next time: Colors and textures. And of course, we get to watch one of our pilot shorts: This BergerTime webisode is called THE CHEAP GIFT. Enjoy! You can view it below.
Joaquin Gil is a filmmaker, artist and anthropologist, creator of the ?Video Editing Master Class? series currently available in DVD. His most recent production is the e-Film ?The Outsider? starring Catie Boles, completely made in the digital domain.
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