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Marshun
11-27-2009, 04:14 PM
What about this:

How do you benefit from referring to those frames of references known as "locals" and "globals" for animating?

Marshun
11-29-2009, 11:06 AM
Nobody knows?

dwburman
11-29-2009, 12:00 PM
I don't understand the question. :)

Marshun
11-29-2009, 04:40 PM
Hi dwburman.

I thought this might be a problem. I had just finished reading Poser 8's use of its terms: "Local" vs "Global" rather than finding and using Lightwave's terms "Local" and "World". Didn't want to hunt lightwave's terms down and got too lazy. Even though lightwave has also used "Global", now and then*.

The following is from Lightwave's reference manual for v8.3:

"World and Local Axes"

"Objects in a scene also have axes and, thus, an "Origin", called the local Origin. When an object is first loaded, its local Origin is lined up with world Origin. Morever, its local axes are lined up with the world axes. However, once you move or rotate the object, this is no longer the case. LightWave provides functions that let you move and rotate items using global* or local axes. Now, most of the time you'll use World, but sometimes using local will be invaluable.

"To illustrate the difference, let's say you are standing in the middle of a one-room house facing the front door. If you held your right arm straight out, it would point to the right side of the house, and your left arm would point to the left side of the house.

"Now, let's say you turned 90 degrees clockwise. (You'd be facing the right side of the house). If I told you to point your right towards THE HOUSES'S right side (global* axes), you'd move it straight out in front of you. However, if I told you to point your right arm to YOUR right (local axes), you would point to the back of the house."
- - -

No wonder someone else's special theory is difficult to grasp.
So that's it. If animators do rely on this, or these, concept's', then I'd like to hear how they got it figured so they can do their work without gettin' dizzy.

dwburman
11-29-2009, 11:53 PM
I don't know if this is what you're looking for.

In Layout, in the Modify tab, in the General Section you can set the Coordinate System to World, Parent or Local. If I'm trying to move something and it isn't moving the way I want it to, especially if it is the child of something else, I just change that setting until it works the way I want it to.

Marshun
11-30-2009, 01:49 AM
...In Layout, in the Modify tab, in the General Section you can set the Coordinate System to World, Parent or Local. If I'm trying to move something and it isn't moving the way I want it to, especially if it is the child of something else, I just change that setting until it works the way I want it to.
That is correct. You are substituting one of each of the world, parent, or local frames of references to get the kenetics right. If you didn't have that tool, how would you make your next entry? Consider what you're basing all the actions on. That is, how would you know how to make your next entry in order to get it right?

Einstein (now you did it) used his theory of equivalence to understand how acceleration and gravity are the same, making gravity just another form of acceleration. And that your standing on the ground, is the same as going up in an elevator. Or that you're accelerating upwards through space itself! Or that space, itself, is rushing downwards around you.

Back to the frames as local and world, how do you know which frame to use so you don't make another error while animating?