::- Which one is better one bone(IK/FK) or three bones(IK/FK).
::- How to stretch three bones IK/FK.
::- How to manage the shifting of three bones IK/FK thru higher order bones(i.e. hip and hipsway and clavicle). Though it is still managed.
::- In my bone(three bones IK/FK) I have one input/output order of skincluster and bindpose is different of ball bone(left). How to change that i am unable to drag it.
::- How do people achieve many amazing effects like shortening of legs.
::- What all is needed in medium flexibility(I can do thru one bone (follows + locks + stretch and squash(with controls) + rivets + blend shapes + reverse locks + twisting(w/o strecth) + twistable spine(from top and bottom which is bendable) + working on rubberhose(maybe that also))
::- How to achieve stretching of FK bones.
Thanks.
some issues with IK/FK
Hi there,
I guess most of these questions have been answered umpteen times already. Maybe you didn’t do search with correct key words, so here are some for great posts, mostly related with FK/IK blending.
“FK/IK seamless switching in 3ds max 8”
"ik/fk swap + stretchy bones + twist bones = huh?"
“Squash & Stretch Rig”
Hope this helps!
Based on the original post I think he’s using maya … or maybe xsi… can’t help there
but i’ll do my help to answer (based on max tho)
::- Which one is better one bone(IK/FK) or three bones(IK/FK).
do you mean using 1 chain of bone for IK 1 for FK and 1 for Blend?
if so: as far as I know the blend system would give you more flexibility between options.
::- How to stretch three bones IK/FK.
Apply the same logic as with a 2 bones Leg/Arm but take into consideration that you have 3 parts instead of 2 in the scretch script. You will normally use the stretch only for the IK but you can do it with an FK setup also…
::- How to manage the shifting of three bones IK/FK thru higher order bones(i.e. hip and hipsway and clavicle). Though it is still managed.
not quite sure to understand that either
::- How do people achieve many amazing effects like shortening of legs.
stretch without squash
::- How to achieve stretching of FK bones.
In max you parent your bones to a Spline using a path contrainst + look at ( so the keep the shape of the spline), and assign controller to this spline… so stretching the spline will also stretch the bones… to get the FK effect simply link the controllers in the desired order between them.
rubberhose:
Pretty much like the Fk but its driven by an IK … you can still move the subcontroller to deform the spline path contrainst.
twisting(w/o strecth)
Create the twist bones and set them up using the blend systemlike you would do normally… however twist bones not affected by stretch is possible but would create an odd effect.
If you stretch your arm to a length of 10 times the original size the vertices will also stretch according to this ratio however the vertices skinned on the twist bones wont stretch.
If its what you want… I would simply disable the Scale stretch in the bones options so the bones always keep the same length no matter what you do with it
Hope it helps.
Hi,
In response to your rig stretching questions I think some concepts that are helpful are
-shearing (what happens when we scale something that has things parented to it)
-pictures (showing before stretch and after stretch and labels for the things we need to measure, here’s a small example for ik stretch by translation, i think similar ideas can be applied
to other kinds of stretching fk,spineIK
scale based stretching)
Heres an example I illustrated http://www.flickr.com/photos/76278515@N02/6884370764/
For the picture, on the right in dark blue is a set driven key graph. On the left is a 3 joint chain in two poses. The first 3 joint chain pose is at default, the one to its right is with it just before we would want to stretch it. The left graph shows that the top of joint chain default length is A and the bottom of chain default length is B.
On the set driven key graph the horizontal axis is the distance between the ends of the joint chain. This distance is updated anytime we move the animator control at the hand (because animator control should be moving the thing keeping end of our measurements). The vertical axis is the translation down chain. Assuming down chain axis is X, A 5 on vertical for the top line labeled “up” would say the translateX of the middle joint in the left picture is 5. A 5 on vertical for the bottom line labeled “low” would say the translateX of the low joint in the left picture is 5.
On the set driven key graph, distance < = (A+B) we see no change in graph because we don’t want arm to stretch when its total length is below (A+B) so lengths of top and bottom stay unchanged at A and B respectively.
On the set driven key graph, distance > (A+B) we see that the lengths of the top and bottom get longer (we see stretching). In fact at distance 2(A+B) the top and bottom lengths are exactly double. Other values can be interpolated example linearly.
Summary of some helpful tools to understand for stretching
-shearing
-pictures
-set driven keys (how can we tell joints to stretch ex: change down chain translation or down chain scale when a distance changes)
-distance measure tools ( how can we know if we should stretch or not ex: could use distance, or curveInfo nodes to measure stuff)
Regards,
Nate
Inspired by Jason Schleifer’s Animator Friendly Rigging (jasonschleifer dot com)
Q)::- How to stretch three bones IK/FK.
Apply the same logic as with a 2 bones Leg/Arm but take into consideration that you have 3 parts instead of 2 in the scretch script. You will normally use the stretch only for the IK but you can do it with an FK setup also…
Ans) Just make all bones of FK parent constraint,or what. Is IK and FK blendable after stretch thru orient constraint blending.
Q)::- How to achieve stretching of FK bones.
In max you parent your bones to a Spline using a path contrainst + look at ( so the keep the shape of the spline), and assign controller to this spline… so stretching the spline will also stretch the bones… to get the FK effect simply link the controllers in the desired order between them.
Ans) this are you saying for spine.I have done DT(production rigging).Are you saying that.
Q)rubberhose::-Pretty much like the Fk but its driven by an IK … you can still move the subcontroller to deform the spline path contrainst.
Ans)i am doing rubberhose from dennis jenson.i think it is best .is it all I need.
Q)::-I have done IK/FK thru one bone only because there are many tutorials on that.Do I have to learn it thru 3 bones(blendable) system, whose tutorials are very difficult.I am learning puppet rig. Which is difficult.And also, I have learned bipedal rigging series. i think I have to learn now feature rigging.That is too difficult.
Q)::- I cant understand what ogbonna said.But, I have done stretching thru DT(cartoon character(many times) and puppet rig(many times) and one also done from feature rigging(once).
Q)::-Should i buy cgtoolkit vol 1 2 3 art of rigging.Is there anything helpful in that.
Q)::- Should i have to learn puppet rig in that twisting is very good.Though it is very difficult?
Q)::-Can’t i get a job for basic rigging and medium flexibility ,after doing this all.Should I start trying for basic rigging.
Q)::- How to manage the shifting of three bones IK/FK thru higher order bones(i.e. hip and hipsway and clavicle). Though it is still managed.
not quite sure to understand that either
Ans) when we move clavicle then there is one main bone and two other bones which are to be blended.When main bone and other one that is fk or ik is blended with main bone.And then two bones goes at one place and other one goes at another place,because when we move clavicle bone it operates on all three bones.because clavicle bone is not blended ,but it is above that(i.e. arm bone, or as it is said as above humerus bone like i have done in bipedal rigging series(demon rig)).
This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.