This technique gets interesting if you are using a parametric object or just want to cache some computationally intensive deformers like the Displacer for example. The basic hack consists of setting the Jiggle Deformers strength to 0% so it's not influencing any animation but using it's ability to cache the animation. Which will still work despite setting the deformer's strength to 0%. (no audio)
Edit 7. April 2014: Look for Douwe's comment on using the Point Cache Tag on a Correction Deformer as a another way of caching, very hacky and very nice :)
Metaballs take the points/vertices on your geometry and turn them into a bloblike object.
As the point number on your geometry/animation increases the calculations inside
the metaball object increase, which results in a very laggy viewport.
Using one point splines in conjunction with a cloner or an emitter for example
you can speed up significantly your metaball workflow as you control exactly
how many points get calculated.
Also keep in mind that the Exponential Falloff setting in the Metaball Object
can also slow down your performance as the underlying algorithms are more complicated.
So use it with care.
For everyone claiming you could do the same with a Matrix Object, just take one, set it to one
matrix clone and convert it by hitting c. If you look into the structure manager
you'll see that one Matrix Object clone consists of four points as this is how he handles PSR
transformations.
There is an old tag dating back from version 10 called tension tag as part of the mocca module which reacts to deformed polygons. It's basically gives feedback as where polygons are stretched and squashed and writes this back into a vertex map. With this vertex map you can generate extra wrinkles and creases dynamically on your geometry.
It's intended use is on the material level, more specific for restricting bump, normal and sub-poly displacement on affected areas. Here's a way to use it for example with a displace deformer in order to have direct viewport feedback. As every deformation gets recognized by the tension tag, you can't use the displace deformer directly on your geometry, this would result in feedback loop. You have to make a copy of your setup and map the generated vertex map on your copied one. A little bit of xpresso can help you with that.
Having viewport feedback has one downside, which is that your actual geometry has to be dense enough to give enough topology to deform.
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The Jiggle Deformer has a forces tab which can be easily overlooked, where you can drop in particle modifiers. This is a great way to use them as deformers on geometry. This results in very organic motion and behavior. Modifiers who have an actual effect are wind, gravity, attractor and turbulence. Keep in mind that by their nature all modifiers work 3 dimensional as their original purpose is to modify the PSR of particles in 3d space.
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