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dOMINUSMess
11-22-2005, 03:18 PM
Hi, I'm doing Joe Cosman's rigging 1 tutorials and have come across a coordination issue that puzzles me.

In the video, Joe parents the hand bones to a null for IK purposes.
Before drawing the bones, he positions the null so the bones that will be parented to it will be aligned to that null's orientation.

So far OK.
But my model has it's hands horizontal and Joe's model has it's hands vertical, and not paying attention I ended up with hand bones whose Pitch is where the Heading should be.
I said "So far OK" because I know what I've done wrong and how I should have done it : I should just have adjusted the null's Heading +90, and should have left the null's Bank as it was, then the bones would have aligned correctly.

Before doing all that positioning over again, I was looking for a way to correct my mistake without having to do it all over. But I guess there's no way to do that. (Maybe there is, but I would'nt know it.)

In my messing with the null and the bones however, and here's what my question is about, I noticed that when I grabbed the null's Pitch on the edit sphere, I expected it to follow the "orange Pitch edit sphere cirkel", but it did not do that!
Instead when rotating the null's Pitch, it rotated along the "dark purple circle of the Heading".
When I rotate the hand bones' Pitch, the rotation does follow the "orange Pitch edit sphere cirkel" as I expected.

In the picture you see the hand bones being rotated on the null's Pitch.L
Viewing from the top I expected the bones to go front and back when Pitching the null, but instead the bones rotated up and down???

If you can make sense of my explanation: could you explain this behaviour to me?
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http://users.skynet.be/dominus/nonwebpics/coords.JPG

maks
11-22-2005, 04:23 PM
Are you using the old coordinate system (turned off the coord buttons on the right of the screen)? Then your LMB would work in parent coordinates, while the editsphere still draws in local coordinates. In this case the right mouse button would work in local coordinates.

dOMINUSMess
11-22-2005, 06:21 PM
Are you using the old coordinate system (turned off the coord buttons on the right of the screen)? Then your LMB would work in parent coordinates, while the editsphere still draws in local coordinates. In this case the right mouse button would work in local coordinates. Yes I am.
The picture is taken in setup mode and the strange thing is that the bones "Pitch" with the left mouse button and right mouse button, while the null rotates on "Heading" with left and right mouse dragging the Pitch!

Guess I should read the manual again and again til it makes sense.

maks
11-22-2005, 06:36 PM
With the old corrdinate system, if your null has a rotational offset from its parent, i.e. not 0,0,0, then the left mouse button rotates it in its parent's coordinate system, so in your case, on the parent's pitch axis, and with the right mouse button on it's own (local) pitch axis.

dOMINUSMess
11-22-2005, 07:05 PM
Hi maks.

That was fast !
Thanks for the info.
I guess I need a lot of fiddling around with it and reading the manual again and again before it'll sink in.
All that local and parent and world stuff is getting the better of me at the moment.

( System overflow... Will be back online soon :banghead: , hehe ... )

I'm at least getting the rigging to work right.

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