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Important questions about bone rotations on frame 0!

Posted: Mon Jun 30, 2008 8:41 pm
by heyvern
This is a very important question that pertains to many of my scripts. How do you assign bone rotations on frame 0?

Do you just use the bone rotation tool?
Do you type in values?

If you create a symetrical bone rig for a character (front view left right matching bones) do you assign negative values for opposite bones (90, -90) or do you use the opposite value within 0-360 (90, 270)?

These are critical questions. I type values in on frame 0 sometimes, sometimes I use the rotation tool.

My flip bones script uses negative values for opposite bones... which now I think is incorrect.

On frame 0 no negative values are allowed for rotations of bones. If you type them in they are used, but if you touch that bone with the rotation tool it immediately reverts to a value with 0-360.

I was not aware of this. I incorrectly assumed that rotation values on frame 0 were identical to other frames... They are not.

I am fixing my flip bone script (simple fix) to eliminate potential problems

-vern

Posted: Mon Jun 30, 2008 11:02 pm
by synthsin75
I always use the translate bone tool to adjust any angles I need. This sounds like a best practices, considering your troubles. The translate bone tool seems to just reset the initial value.

I never use the rotate bone tool (text input or manual) on frame zero. I don't know why, just always seemed easier to do all my tweeking with the one tool.

It seems to me that the rotation on frame zero should always be the initial (zero angle) for the whole thing.

Posted: Tue Jul 01, 2008 12:59 am
by heyvern
Using the scroll wheel in the rotate text box also is incorrect. It should not allow negative values or values over 360 on frame 0.

I agree. I think all bone rotations should be FORCED to fit into 0-360.

I feel really stupid now because my copy flip bones script was hard coding in negative values on the flipped bones. I fixed it now but it could have been used to create a lot of problematic files. I had no idea. ARRGGGHHHHH!

If a value isn't suppose to be there, then it shouldn't be allowed to be entered.

-vern

Posted: Tue Jul 01, 2008 1:11 am
by synthsin75
Yeah, I don't understand why you'd need it to remember that you rotated it like 50 times on frame zero. :P At least I don't think there's any 2D animation task that would require unwinding anything. Even if there were, you could wind it up on frame one, then it would 'unwind' toward the next key.

Posted: Tue Jul 01, 2008 6:19 am
by heyvern
I wouldn't be surprised... if I was the only one who did something like that... put in odd rotation values on frame 0 <sigh>. I wonder now how many of my scripts were effected by this?

I know one thing for sure. This explains some odd bone "spinning" behavior on keys I've experienced in the past. I can remember cases where I must have "bumped" a bone frame 0 with the rotate tool causing it to change without my knowledge and then wondering why my keys were flipping around oddly. I think I just fixed the keys rather than try to figure out what caused the weird rotation in the first place.

It didn't happen very much.

-vern

Posted: Tue Jul 01, 2008 10:29 am
by funksmaname
i never type in numbers for anything pretty much - i use bone rotation tools... i will use the middle mouse button for changing rotation constraints though...