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View Full Version : IK/FK without sliders, how?



Hominid 3D
07-24-2011, 05:38 AM
Hi. Id like to construct an IK/FK arm similar to what Ive seen in max. In other words, Id like the possibilty to rotate the ellbow in FK and the hand target goes with the arm, and then grab the hand and the arm follows in IK. Is that possible to build in LW?

Thanks guysn gals!

RebelHill
07-24-2011, 06:46 AM
basically, no.

Hominid 3D
07-24-2011, 06:56 AM
I think I saw something to that effect once on another LW forum. I think it was pooby who made an armrig with that behavior, but I cant find it anymore.

Hominid 3D
07-25-2011, 06:11 PM
basically, no.

Hey RH, thx for the reply. Youre an inspiration, man.

Do you usually use LWs relatively new IK/FK blending or do you prefer the 3 arm blending method?

Skywatcher_NT
07-26-2011, 03:12 AM
Ik booster can do this :thumbsup:

RebelHill
07-26-2011, 04:48 AM
Depends on the situation. LWs built in IKFK works well, but the problem is the use of the IK plane bone/null which has to be blended also. This means, ofc that the actual "character" part of the chain shifts to accomodate the blending of its parents action, making it impossible to make the IK and FK line up or match one another properly, which makes it difficult to get a nice smooth/clean switch between IK and FK during animation. This can, ofc, be remedied by blending the IKFK switch over a set of frames to smooth out the transition, but again this is problematic as during the frames where the chain is part way between full IK and full FK, it becomes problematic to control preperly, and therefore to tween any blend that's not moving as you'd like.

So usually if I do use LWs built in IKFK its usually on chains that have a limited range anyhow (like fingers say) where I can get away without the need for the IK plane item in the chain.

Otherwise, for everything else, I always construct my own out of a plain FK chain, a full IK chain, and use constraints to blend the 2 together, its a ot cleaner, gives better control, and is more natural and intuitive for the animator.

Hominid 3D
07-26-2011, 04:07 PM
Ik booster can do this :thumbsup:

IKB is a riddle wrapped in an enigma without chocolate topping..and LScript hates it.

Hominid 3D
07-26-2011, 04:15 PM
Depends on the situation. LWs built in IKFK works well, but the problem is the use of the IK plane bone/null which has to be blended also. This means, ofc that the actual "character" part of the chain shifts to accomodate the blending of its parents action, making it impossible to make the IK and FK line up or match one another properly, which makes it difficult to get a nice smooth/clean switch between IK and FK during animation. This can, ofc, be remedied by blending the IKFK switch over a set of frames to smooth out the transition, but again this is problematic as during the frames where the chain is part way between full IK and full FK, it becomes problematic to control preperly, and therefore to tween any blend that's not moving as you'd like.

So usually if I do use LWs built in IKFK its usually on chains that have a limited range anyhow (like fingers say) where I can get away without the need for the IK plane item in the chain.

Otherwise, for everything else, I always construct my own out of a plain FK chain, a full IK chain, and use constraints to blend the 2 together, its a ot cleaner, gives better control, and is more natural and intuitive for the animator.

Thx, man. Invaluable input.