I'd like a 'Dynamic' constraint, usually to be applied on bones. It is a 'fake soft body'.

The constraint would just make the bone tend to stay in its position (inertia), accelerating to reach its new position, then oscillating after reaching it (as if the bone had a rubber joint).

Better to explain with images:

http://www.moscafilms.com.br/emilioleroux/blender/dynamicbone.mov


On its simpler form, the constraint would not need a target. Just:

STIFNESS -how stiff the bone acts. How quick or how lagged it will spring to the target rotation

DAMPING - the tendency to stop oscillation more quickly. (A theorethic damping of 0% would make things oscillate forever in real life. That's why cars have dampers)


It would be incremented by other options:

DRAG - something like 'air density', which would make the motion be slower, like underwater -or undersyrup-, without messing with physics.

GRAVITY - an additional value that would try to pull dynamic bones to the world's 'down' axis.


With the advent of pyConstraints, I grew excited and started the project, but now I see I am both new to python and blender, and also my math is very poor. I am willing to work on it, tho, but I need help (or, more honestly speaking, i could help someone).


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I would like to Record mouse movements in the 3D windows, when the animation is playing.

It wouldn't even be necessary to create a shortcut or function. Actually, I can drag objects when the timeline is running, and if Automatic Keyframes is ON, the keyframes are created! but the 'mouse capture' is not possible across frames because the playback pauses each time you grab an object. So the real new feature would be: NOT pausing the playback when dragging things, and adding the keyframes as needed.

Currently, blender has this CTRL-R - record mouse movement in the Ipo window. You can map the mouse to XY curves or XZ curves. It's not very useful because you are restricted to 2 planes, you don't really have a mouse-object visual coordination, and the aspect ratio and strength of your movements depend on the zoom on the IPO window. So I haven't used it very much.

The other way, believe me, would be real useful. I used that a lot in other app, animating 'by hand' and then cleaning up.

After Effects also has something like this called 'motion sketch'.