Trouble rigging a ball with bones(Is it possible to transform from two pivots on the same bone)

[theaaronjohnburr]

HI Everyone!
I’m a blender newbie starting down the Rigging/Animating pathway. I’ve started working my way through the “Humane Rigging” course by Nathan on the Blender Cloud Site but things in the iteration of blender that he is using don’t line up with things in blender 2.82(Or i’m just doing something wrong while following his instructions).

I’m up to the third ball rig, where he introduces bones and armatures. I have made the three bones he has asked for; Spin, Counter rotation and Main.
I have parented the ‘spin’ bone(and armature) to the ball, parented the ‘counter rotation’ bone to the ‘spin’ bone and parented the ‘Main’ bone to the ‘counter rotation’ bone.

I’ve managed to get the control bones to affect the things I want them affecting(Spin turning the mesh, main controlling squash and stretch and the direction of the squash and stretch, and counter rotation doing its thing without needing to have a specific handle).

my problem
The custom bone shape I made for the Main bone rotates off of the ball when I rotate it.
This makes sense to me because the pivot is down the bottom of the bone(which is also the base of the ball, so when I squash/stretch that point stays in contact with the ground), but what I’m wondering is if there is a way to have the ball scaling toward/away from that point at the bottom of the ball, while still having any rotation from the same bone coming from a point in the centre of the ball?

In the tutorial it seems to just be what happens, but in mine that is not the case.

Im Leaning towards it being a problem with the way I have set up the driver on the counter rotation bone, but I’m not sure what I would change to adjust that…

Just about to sleep on it, so if you need more info I can send some screenshots tomorrow morning.

Thanks in advance for your help!

[stilltrying]

Can’t tell anything without a blend. But, if you are using Nathan’s tutorial, you should have a completed blend file to check against yours.

[ajcdfin]

@theaaronjohnburr

I’m up to the third ball rig, where he introduces bones and armatures. I have made the three bones he has asked for; Spin, Counter rotation and Main.
I have parented the ‘spin’ bone(and armature) to the ball, parented the ‘counter rotation’ bone to the ‘spin’ bone and parented the ‘Main’ bone to the ‘counter rotation’ bone.

I hope you have just mis-stated this, parenting is; Main > Counter Spin > MCH-Spin > Ball // Spin.

@theaaronjohnburr

The custom bone shape I made for the Main bone rotates off of the ball when I rotate it.
This makes sense to me because the pivot is down the bottom of the bone(which is also the base of the ball, so when I squash/stretch that point stays in contact with the ground), but what I’m wondering is if there is a way to have the ball scaling toward/away from that point at the bottom of the ball, while still having any rotation from the same bone coming from a point in the centre of the ball?

In the tutorial it seems to just be what happens, but in mine that is not the case.

Re-watch the video - towards the end, post .blend file too
Don’t worry too much about the versioning difference it will work the same.

[theaaronjohnburr]

OH YEAH!
I totally forgot about that. I’ll check that out before I ask any more questions. If I CAN work it out for my self that would be great.

Thank you for the reminder.

[theaaronjohnburr]

@ajcdfin

I hope you have just mis-stated this, parenting is; Main > Counter Spin > MCH-Spin > Ball // Spin.

Yep mis-stated. That was my first issue and I worked out what the problem was as I was typing it out to ask.
edit
Turns out I had them right the first time, redid them backwards, fixed them forwards again and broke the MCH_Counter_Spin driver in the process(counter spin and MCH_Counter_Spin are the same bone).

@ajcdfin

Re-watch the video - towards the end, post .blend file too
Don’t worry too much about the versioning difference it will work the same.

I’ll have a look at the blend file that came with the tutorial(that I forgot about), and if i’m still struggling to work it out I’ll be back with my own blend and more questions.
Good to know that the difference in versions shouldn’t make a difference. Thanks

[theaaronjohnburr]

Okay, I downloaded the blend file from the tutorial and it didn’t really help me work anything out. I managed to break the driver I had working before and now I cant get it working again(I’m not sure why, but I am guessing something to do with the parenting order).

I’ve got the parenting in the same order as the blend file from the tutorial(which turned out to be backwards after all, I had to select in the opposite order to the DVD to make that work the same as he had), the ball is staying in the ‘Main’ rig box that I have made, the spin controls work fine, but now its just the counter-spin that doesn’t work.

Another question I had was about the custom bones and the logic behind where they move to when you attach shapes. I managed to get them to roughly where I wanted them for the handles of the rig, but it was mainly by shifting it a little bit, reattaching, seeing where it ended up and then shifting a bit more. But the translations didn’t seem to be consistent from bone to bone so i’m wondering if anyone knows of a decent video explaining how that works?
EvenBetter2dBallRig(WithBones).blend (708.1 KB)

Edit
Fixed it!
I had Set the object of the counter rotation driver to the wrong bone(MCH_Counter_Spin rather than Main). I had done it right during the first time through, then as I was pulling it all apart and putting it back together based on the sample .blend file I redirected it to the wrong bone.

So my initial problem was the parenting direction(which was sorted out by reversing the selection order from what was given in the video).
Second was just a mistake when I fixed the first problem.

Thanks again for the reminder that the tutorials give you access to the .blend files. Thats a really helpful thing to have and Should prevent a lot of pointless questions in the future.