Can't find info on bone constraints in Help

[Stephen X]

Hi everyone. I'm trying to learn everything I can about the software and have been going through all the tutorials. I couldn't find any info to explain "position control bone" and "scale control bone" in the Bone Constraints menu.

Can anyone explain the use/need or where I can find more info.

Thanks a HEAP!

Cheers
Stephen

[heyvern]

It's fairly simple.

First off, constraint TARGET bones need to have a name. You select the bone with the bone select tool and type in the name in that text box at the top.

Select another bone you want to constrain and open the constraint window by clicking the bone constraints "button". The bones being constrained do not need a name. But the target needs a name so it can be selected in the constraint window. I save trouble and name all of my bones.

The constraints do pretty much what they say. You select the bone you want as a target for the constraint and type in a value.

NOTE:
1 = 100%. So 0.5 would be 50%, 0.25 = 25%, 3 = 300% etc. You can use numbers higher than 1 and also negative numbers.

In the angle control it does just that... the bone being constrained will rotate like the target bone set in the constraint window rotation or angle section.

Translation same thing only it has separate settings for the x and y movement. The constrained bone will move like the target bone in those directions based on the settings.

In use these have incredible power. You can create fan bones for joints. Like at a knee or elbow to smooth out the motion when a limb bends. You can have a bone for a bulging muscle when an arm is bent.

If you get really fancy you can create complex rigs for controlling elements like eyes and eyeballs. For instance dragging just one bone could move both eyeball bones in unison. If the head is a 3/4 view and one eye is smaller because it is "further away" you can change the percentage of the constraint to compensate for this.

The angle limit at the top of the constraint window will limit how far a bone can rotate. This can be useful for arms and legs that shouldn't bend backwards. That does not need a target.

Bone dynamics is a whole other story. I don't use it very much so your own with that one. It is used to make bones "wiggle" realistically, like a springy antennae or a long pony tail.

I... love... bone constraints. I use them... too much some might say.

-vern

[Stephen X]

I swear, you are making a habit of coming to my rescue!

I totally get it. Do you have examples to share how you used constraints? I love the eyeball idea. I am just trying to figure out how to use this for practical purposes.

Is there any place on the forum that goes into more detail?

As always, I am in your debt.

Thanks

S

[heyvern]

There is a section either in the help or one of the tutorials that uses the bicep bulging muscle concept to explain constraints.

The way I learned... I just did it.

I loaded up a file with a bunch of bones and fiddled with constraints until it all made sense. I started to see how I could do more stuff.

They aren't hard to get a handle on once you have played around with them. They are very simple and they just do what they do. When you drag a bone... another bone with a constraint moves. When you rotate a bone... another bone rotates...

As for examples of use... that is so varied and huge the skies the limit.

My character rig has bunches and bunches of constraints... rotation constraints... translation constraints... negative values... 300% values... all these things happening to reach an end result.

The eyes... man... I created an eye rig with a top control for moving both eyeballs and a secondary control for each eyeball separately. the trick is figuring out the relationships and hierachies of the bones.

There are some really crazy things you can do with constraints. Like putting a translation constraint targeting the PARENT of a bone. You get this cumulative effect. Like a big spring. Put a chain of child bones with constraints on each to the next bone in the chain... really wild.

Genete was instrumental in the creation of my face rig. He came up with this ingeniously simple 3 bone rig that simulates a 3D rotation. Completely based on constraints.

This is how I learned it. I just started doing crazy stuff and started getting my head buzzing.

------------

Samples below are "Moho" but they work with AS. They were created with the "original" application.

here's a very extreme example.:

viewtopic.php?t=7724

A simple single eye with eyelid controls. One bone controls both upper and lower eyelids:

http://www.lowrestv.com/moho_stuff/eye2.mov
http://www.lowrestv.com/moho_stuff/eye.moho

A two eyed slightly 3/4 view eye rig with scale and eye angle compensation (in the moho file move the "eyeball mover" bone not the "Global eyeball mover" bone. The eyes move "opposite" of each other to account for the angles of the eye's shape. The global eyeball mover is to adjust both eyes together for looking down or up):

http://www.lowrestv.com/moho_stuff/eye_test.mov
http://www.lowrestv.com/moho_stuff/eyeballrig.moho

-vern

[Stephen X]

VERN!!!!!!

This is all incredible. I can't wait to sit down to digest it all today. This is some amazing stuff. I really can't thank you enough. That was more than I ever thought. I looked at the quicktime files, and wow!

AS should really just collect and post yours and others advance tutorials/sample files in an area for people to look at and absorb. I have been trying to download as much as I can from the site for the past week. It would be great to have it in one accessable area.

You're a peach!

Cheers
S

[heyvern]

Thanks Stephen, I am thrilled to help out.

The truth is I need to put together some tutorials in an organized fashion. I keep writing all this stuff scattered all over the forum. One of these days I really need to go through and find everything and organize it in a pdf..

My problem is I love to share this stuff and I tend to "plunk it down"... where ever... when ever some one asks.

Many times I haven't even thought of these ideas till I start to write my responses to questions (I constantly go back and edit posts adding things).

Thanks for the words. They really make me feel good.

-vern

[Stephen X]

I have to say that if you did put something like that together, you would make my LIFE! AS is great at explaining the basics, but they never get into the shear power of the program. Just what you sent me was incredible. I can't thank you enough.

Let me know if you have any good switch layer stuff lurking around. Bones, switch layers and actions are what I am really trying to focus on now. I got the drawing part down. Now I am just trying to unravel the mechanics of the animation.

Thanks again!
S

[heyvern]

Bones on switch layers.

Here's a tip for hands...

I use a switch layer for "flipping" or turning hands. Using bones I can move the fingers closer together and then use the switch layer to switch to the back of the hand layer and move the finger bones apart again.

The two layers for the hand switch are absolutely identical. The only difference is shape ordering. So you have one hand layer. Duplicate it and just change the order of the finger shapes or any other shapes that need to go from front to back.

It's kind of weird and you have to think about it hard to figure it out. The pinky actually becomes the index finger by the change in shape order on the second layer... and visa versa.

So the turn sort of... goes half way with all the fingers lined up... then the switch happens... the pinky becomes the index the index becomes the pinky (different shape order on the second switch layer) and then the bones reverse direction going back to where they were, but now it looks like the hand has turned over... it's all an illusion...

Adjusting the position of the finger bones you can change their length to account for the finger switch (pinky is shorter than the index)

http://www.lowrestv.com/moho_stuff/larry_hands2b.mov

EDIT:
The thumb is not "connected" so it just slides to the other side of the hand using its bone.

Place the turning sequence in an action for quick and easy use.

-vern

[Stephen X]

OMG! It keeps getting better. Do you have the AS file that I can look at?

I figured out on my own the layers aspect when really learning drawing over the past month. I was stumped as to how to flip the hands around. I had no idea that it could be seamless.

You are the best!
S

[heyvern]

I'll look around for that file. It was just a test file for a larger character file but I may still have it.

-vern

[Stephen X]

You are ACES!!!!!!