max bones setting

[goo_leo]

hi people, I need help with the 3d max 5 bones. I need them to stretch (for example when the character in going to jump), to make it more elastic.
I know it has to be something with the max script but how??????????????

[Clalan]

there are many ways to set up stretching limbs. you could create an IK leg that automaticly stretches out as you the end effector too far. you could create a normal IK leg with a squash / stretch attribute so you can control it manually. or you could make elastic legs, with crazy stretch and bends.

anyway, you can do it through scripting, but you can also do it through constraints. if you give me more details on how you would like to control the stretching then I could help you set it up.

[goo_leo]

Exactly. I want my character limb to create a normal IK leg with a squash / stretch attribute so I can control it manually.
If you could explain me step by step how to do it, it would be great

[Clalan]

hey,

I quickly threw something together which is a nice start, but there is a lot of room for improvement.

http://www.alanclaes.info/bounceleg.zip

check out ctrl_foot, it has a couple of custom attributes:
squash: max squash (0 - 100%)
stretch: max stretch (100 - 1000%)
bounce: this slider controls the amount of squash and stretch withing the limits set above.

for this setup I used float scripts. take a look at the x_position animation controllers for bone_lwrleg and null_leg. the x_position of a bone determines the length of the parent bone, so you can use this for stretching. I calculate a stretch ratio from the values of the custom and multiply this with the original parent bone length.

downside:
- the foot and hip will stay in the same position, so increasing the bones length will just push the knee further away... not very intuïtive while animating. I have an idea that would make it better, now just find the time to execute it
- float scripts can get slow.. I'll try to get everything working through constraints or expressions.

but anyway, take a look at this.. see if it's sorta what you are looking for.

[goo_leo]

Thank you very much Clalan, i think that would be really helpful