Stretchy IK just using nodes

[david p]

Hey all

In my noob naivety I thought I would try to work out stretch IK using nodes. Heres what ive made

I know the script is not an expression but i wanted to try

up arm dist

low arm dist  

sum of these added manually.....connected into clamp node min=sum of two joint lengths

                                                                                       max set to an arbitrary 100 

                                                                                       input is the arm loc to hand loc distance  

the clamp node just stops me getting a distance value less than the non stretching length

I need to factor in global scale naturally but thats easy enough

It seems to work...but anyone see issues with this? 

I so prefer nodes to script!

[david p]

Just to add, it was pretty easy to use the blendTwo attr choice for the elbow lock with this clamped output setup, i just had to make sure i was sending two translate values to the blendnode where earlier i was working out a scaling factor then connecting to scale.X on thejoint. Took a bit of working out the ratio of each joint to the sum of the two but it works.!