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pdp editor
11-28-2007, 04:43 PM
I'm trying to create an amination where three objects roll into the camera view one after the other 75 frames apart. The problem is although I have key frames to prevent the other from moving until it's turn. When finally add a keyframes to move the object closer towards camera; some of the rotation and scaling affects the object before the intended keyframe causing weird results.


Question: how can I animate an object freeze it in place for 75 frames then have it crawl towards the camera rotating and increasing in size without the last changes affecting the 75 frames where the object should remain still?

RudySchneider
11-28-2007, 04:46 PM
Have you tried setting the tension of your envelopes (motion, size, etc.) in the graphic editor?

pdp editor
11-28-2007, 05:33 PM
I have no experience using this part of LW. Is that where the problems are?

medicalart
11-28-2007, 05:50 PM
Under the layout main window is a button "Autokey". If that's selected, any slight adjustment you make will be recorded whether or not you manually key the frame. In either case, the graph editor will solve your problem.

Open Graph Editor.
You need to select your object from the list of objects at the bottom. That puts a list of channels at the top. Select one (or more) of the channels from the upper list. The curves on the main graph correspond to these channels.
Keyframes are indicated as dots on each of the curves. Select one or more of the dots, and then change the "incoming curve" setting (bottom right, under the graph) to "linear". You'll see the curve change to a straight segment near the selected keyframe. You many need to move, or add, or delete keyframes--all of which you can do from this window.
It's really the only way to get precise control of motion.

pdp editor
11-28-2007, 05:58 PM
OK I been working on this for an hour; here's what I have. two key frames one both have the object moving in front of the camera. Problem something between the two key frames is telling object to fly into and pass the camera then respond to the next keyframe. it is as if it remembered something about deleted keyframes and has stored this information somewhere to respond to inbetween actual keyframes. How do I delete this non-keyframe action?

pdp editor
11-28-2007, 05:59 PM
auto key frame is off.

pdp editor
11-28-2007, 06:29 PM
thank you- I'll try this now

pdp editor
11-28-2007, 07:24 PM
Look at the graph editor attachment; keyframes 50 and 100; see the nasty little downward hump in the middle, LW does this automaticlly. Key frame 100 is a duplicate of fifty, why does LW animate the frames in between. frames 51 to 100 are freeze frames, ie no movement allowed. And yes I tried fixing the hump that only adds more animation. besides if you look closely at the hump there is no keyframe in the center of it. :devil:

pdp editor
11-28-2007, 07:59 PM
I found the problem: TCB splines should not be used.

RudySchneider
11-28-2007, 08:07 PM
I'd be careful about neglecting TCB splines altogether. After all, a rolling ball doesn't usually come to an abrupt stop. It gradually slows down. If you want to ensure it stays stopped before the next move, you can insert another key right after the "stop" frame, and another key just before the key where motions starts again (if that's what actually happens, that is).

medicalart
11-28-2007, 08:40 PM
You can change the default from TCB to something else if you want, but RudyS makes a good point, that for many motions TCB splines keep things from jerking around. You should use the graph move tool and adjust the keys a little and use groups of keys--maybe 3 frames in a row--and mix linear with splines.

Surrealist.
11-29-2007, 05:27 PM
Look at the graph editor attachment; keyframes 50 and 100; see the nasty little downward hump in the middle, LW does this automatically. Key frame 100 is a duplicate of fifty, why does LW animate the frames in between. frames 51 to 100 are freeze frames, ie no movement allowed. And yes I tried fixing the hump that only adds more animation. besides if you look closely at the hump there is no keyframe in the center of it. :devil:

This is really just the most simplest example of what curves do. Remember it is a curve. A point on a curve is merely a control point. Curve editing is a professional tool for animation. Available in all professional animation packages. Without it, animation lacks the subtlety and fluidity that happens in the real world. So, you have learned the first lesson in what happens to a curve going though a point.

Obviously there are times when LightWave cannot read your mind and assume you don't want a curve to be a curve. In this case you have to tell it no, at this point I need you to give me a full stop because at this point nothing is happening.

This is one of the most common things you do in editing curves in your animation.

You have two keyframes there. We will call them B and C for illustration. Between them is a slump.

This is not your problem. The problem is what precedes the slump.

The keyframe prior to these frames we will call frame A for illustration. Keyframe A has a higher value than keyframe B.

Frame C is more or less not an issue other than it comes after B and happens to be the same level. A similar problem could occur even if it was not.

What you want is for the animation to rest at frame B and have no movement from B to C. Or in the case of C, being different than B, no unnecessary overshoot.

To do this set the TCB value of Tension for frame B to 1 and you will have a perfectly flat line between B and C. You will also have a smooth incoming curve from A to B and come to a gradual stop which is much more natural than what you would get with a Linear keyframe.

Keep this in mind because if you want your animations to look nice, you'll be using this a lot. And I do mean a lot. Like pretty much every time you animate anything.

In the case I eluded to above where C was not the same as B, you can use:

Tension to control how tight the curve follows the keyframe.

Continuity to control how fast it does this and

Bias to control which side of the keyframe the curve is more apt to fall on.

Play with these settings and see what you get.

Then play with Bezier curves too. Another great way to edit curves. Check it out in the manual.