IPO's W/Out Curves


(TurboG) #1

Ok. I am making an animation. I want an object to stop at one exact point. Because the IPO’s automaticly curve, the object tends to drift or wobbel. I have made them without curves before but now I forgot. Anyone know how to do this? Thanks.


(ilac) #2

Hi,

Select the point (or only the Bezier handle if necessary) and press ‘v’ for vector. To convrt back hit ‘H’ twice for 2 options or ‘Shift+H’ for automatic handles. Oh and make sure the curvs are in edit mode!

Rgds
Fabrizio


(S68) #3

BTW

a sudden stop is nonphysical. Bodies have inertia. I would suggest to move bezier handlers (in edit mode) so that your object came to a smooth stop.

V key is easier anyhow.

Stefano


(harkyman) #4

You need sudden stops, if the stop is caused by collision, which it is much of the time. When your butt sits in a chair, you need the butt empty to stop suddenly. When a bird lands on a log, you need the feet to stop suddenly and precisely when they hit the log. When a person walks, you need their feet to stop moving suddenly when they touch the ground. All of these require a vector key, at least on the trailing side of the ipo. Of course, they also require you to generate motion elsewhere in the model to show continuity of momentum.

But I have found that vector keys are essential in full motion animation.

BTW, if you want to affect more than a single key or IPO at once, you can do a multiple selection and hit the v key. It’ll work on more than one at a time.


(TurboG) #5

I am trying to make somthing rotate and look at a certain object. The problem was that it would turn too far and miss the object because of the curved IPO. Your ideas helped. Thank you.


(ilac) #6

Not sure if these are are suitable for what you want but:

What version of Blender do you have?
With 2.25 you can add a ‘track to’ costraint and then animate the influence. that way your aim is assured!

If on the other hand you have 2.23 you can make a regular track to (ctrl T) to an empty and animate the empty.


(harkyman) #7

Hey TurboG -

Whether you just rotate the object in question or track it to and empty and move the empty into position, you’re still going to have to edit the ipo curve.

In case you don’t know what I’m talking about:

  1. Set your keys normally, for rotation, movement, etc.

  2. Select the object that is over-rotating, and set blender to be at the frame where your key is for the target rotation.

  3. Go into the IPO edit window (looks like an excel line graph)

  4. Select the three rotation ipo curves and hit Tab to enter edit mode.

  5. Select all three key points, one for each curve.

  6. Hit (I think) the ‘v’ key. This should make the curve into a straight line on either side of your key.

You may or may not need to do this for the next rotation key as well, depending on it’s values. In any case, you want a straight, horizontal line running from your target key to your next key.

Good luck!