View Full Version : "KeyForce" Plugin Idea - Please Comment

Mike Pauza
01-30-2007, 09:38 AM

Mike Pauza
01-31-2007, 12:11 PM
The idea is that you key your "force" (white splines), which drives the animation channel. When the force is 0, the animation moves at a constant speed (think linear motion). When the force is >0, the motion curves upward. When force is <0 it curves downward.

This might take some getting used to for pure artists, but it's already familar to techy people, and utimately you higher quality motion because the mathematics behind the motion is exactly how things actually move.

-Mike Pauza

Some Example Mockups:


Mike Pauza
01-31-2007, 12:13 PM
Just want to clarify, that these examples are fudged and that the motion shown is approximate...it's not all that smooth so don't flame me. Hehe.

01-31-2007, 05:35 PM

This looks great - are you developing the plugin?

Mike Pauza
01-31-2007, 07:25 PM
I have the math code, but I've only written one somewhat basic modeler plug, so I'd rather find someone who's really good at Layout plugins and just get it done. If you know of anyone like that let me know. I want to sell this for a minimal fee, and would be happy to split the revenue with someone who's a LW coding whiz BTW. If I find someone like that, I might even want to come out with a bunch of plugs.


01-31-2007, 08:31 PM
For the first sight look, looks like impossible to do task because no 3rd party plug-in can draw into Graph Editor window additional force spline coloured white on your screen-shots.. You would have to rewrite the whole GE to get what you want..

Mike Pauza
01-31-2007, 08:44 PM
That bites.

Can you use a channel keyframe data to modify that same channel?
Like with Expressions, except that expressions don't allow a channel to reference itself.

Or is it possible to have two GE's open at the same time?

Fudging this with multiple channels, looking at one at a time would be
close to worthless.


I guess I should say thanks for bringing this up.
Any suggestions?


01-31-2007, 09:01 PM
Read this
It's channel modified handler plug-in class, probably the only thing exposed in LW SDK which is visible in GE..

02-01-2007, 01:19 AM
Mike ,

Remember my remark on SpinQuad?
That's why I asked if you were going to create a custom "Force" Envelope.
That way you can have the affected channel AND the custom "Force" Channel open at the same time if desired. If you need some help doing that, drop me a line.

02-01-2007, 02:00 AM
Im curious. How does that beats Bezier curve adjustments?

02-01-2007, 08:31 AM
Here's a pic of an added channel and a "supposedly" modified channel:

Mike Pauza
02-01-2007, 09:06 AM
Greg: Just PMed you.

Sensei: Thanks man.

The biggest difference is that with LW TCB Splines you "start out" with speeds that are terribly wrong, and that even after considerable tweaking of TCB settings, the speed is still not that smooth. Although sometimes nice as an effect, unsmooth speeds are noticable during animation and usually look odd. You can see a channels velocity graphically by turning on "Velocity" in the graph editor.

Here's an example for anyone interested:
The first image is just some keys that might seem to have decent motion.
The second has velocity turned on to show how horrible the motion really is.
The third has comprehensive TCB tweaks and looks much much better to the eye, but is still not perfect. It's great for most situations at this point, but sometimes it's still not acceptable...for a camera move with close forground objects for example, the close object make seem to move weirdly even though our motion curve looks pretty good to the eye. A more telling visual for how smooth a curve is, is it's accelleration (the GE can't show this unless you use an expression trick), when tends to magnify any problems you have. The plug I'm talking about uses a smooth acceleration/force and derives the actual motion from that so you get silky smooth motion without a lot of fuss.


Mike Pauza
02-01-2007, 09:23 AM
Thanks Greg. I'll be very happy if LW is able to allow this!
I was getting depressed. :(


02-01-2007, 07:24 PM
Thanks Greg. I'll be very happy if LW is able to allow this!

That's doable, but not as useful as stand-alone version with force.. There must be layout generic tool to attach force channels to regular channels, and user needs to add modifier to channel (I have feeling that there is automatic way to do it, which would be great), modifier is getting channel name, append ".Force" at the end and use this new channel for reading forces that modifies channel values that's currently evaluated..

User is forced to manually select both channel that's edited and force channel attached to it, otherwise not possible to edit forces..