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paperclip
03-28-2005, 12:09 PM
Hi there. I'm new to rigging and I'm following a tutorial in which I am told to orient the local axes of certain bones as follows:


Orienting the bones
Orient the jHip, jKnee, jAnkle and jToes joints so that their local axis are as shown: Y pointing to their child joint, Z pointing up.

Could someone tell me which commands I need to use this? I've looked at the help files but it's just proving confusing. If I try to rotate the axis using 'affect pivot only' in the hierarchies>pivot menu, the entire bone rotates and makes a bit of a mess.

Help!

clalan
03-28-2005, 12:50 PM
it sounds like you are using max and reading a maya tutorial :) as far as I know, it's impossible to change the local axis of a bone, x will always be pointing towards the child. affect pivot only doesn't work as a bone is actually nothing more than a pivot point. but I might be wrong.. in which case I hope someone will correct me!

so X will always be pointing towards the child. and you can change the direction of the other axes by either rotating in local coordinate space with "affect pivot only" on or in "bone edit mode" (this way the child won't be affected).

marktsang
03-28-2005, 03:30 PM
as far as I know, it's impossible to change the local axis of a bone, x will always be pointing towards the child

it is not impossible - i have written a script to change the rotation of bones (to avoid gimbal lock in certain situations) i will post it later

note that all it does it chnage the bone from a bone to and edit/poly / mesh and then rotate the pivot and then change back to bone object - but you will loose all bone options like fins and length so be sure to set them first


mark

paperclip
03-28-2005, 04:26 PM
Wow! Thanks-- I didn't know I didn't have to look further than my own country for the answer :) Great stuff, I was getting worried! Does this mean I can carry out the full tutorial for the knee rig at rigging101? Because that's what I was doing until I ran across this...beast thing.


Thanks once more!

marktsang
03-28-2005, 07:11 PM
hi paperclip,
ok i dont know about the tutorial at rigging 101 as i havent seen it but you can acieve almost anything you can do in maya in max with a bit of jigamapokery :D

my script is here if you have any questtions ect... mail me at marcus_tsang@yahoo.ie

http://www.geocities.com/marcus_tsang/reorientbones.zip


edit:- ok i just realised its not that user friendly considering i made it in a few minutes (with the intention of only using it myself) i should explain how to use it a bit

create a bone chain
run the script
go to the customize ui menu and go to toolbars
create a new toolbar and go to category "mark tsang"
drag bone pivot rotate over to the toolbar

to use:

the best way to use it is to select an entire bone chain to change all the pivots at once

select the bone chain
select the move tool and select local coordinate system and use pivot point center (this is so you can have a preview of the direction of the pivot on the root bone)
click the bone pivot rotate button on the shiny new toolbar you created
now select and axis to rotate around and press the button at the bottom - you can check the reverse checkbox to rotate the other way.
try to do the pivot change in as few presses as possible (plan out which axis to use) as there may be some slight rotations with multiple presses
your done now! :D

im not sure why you might need to rotate bones anyway - i only do it for my scripted rigs that have some slightly weird roatations when i build a rig with a bone who's rotation is close to gimbal lock -> there is probably a better solution than changing the bones pivot - if i get a chance ill look at the site and see if i can help....


mark

paperclip
03-28-2005, 11:30 PM
Thanks a million, very much appreciated indeed. I'll try it out tomorrow and let you know how it works. TDs are geniuses :)

Keep up the good work and thanks once more!
paperclip

marktsang
03-29-2005, 02:36 AM
TDs are geniuses :)

im not a TD! i like to think of myself as an artist :D

just so happen to understand some other more technical stuff too :P

if you need help just hollar
mark

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