Stockmoves Tutorials:
Chapter 1- SoftImage Connection The Basics -

1.1 Importing Stockmoves data

If you've performed the previous tutorials you should now have a Stockmoves .umf file (you could also use one of the free example .umf files provided on the web page) and a converted scene for your package of choice. This scene contains a hierarchy to which we are going to constrain our skeleton to during this tutorial.

First of all we will start by loading in our default skeleton. With Softimage 3D, you can go to the motion module and perform a "Get - Skeleton - 19DOF"

Default skeleton

This will bring up a simple, standard skeleton which was also used for capturing data for Stockmoves.If you're using another package, you should check the Stockmoves user pages and download the appropriate scene containing a similar skeleton.

Later in this tutorial we will elaborate more on setting up your own skeleton. But for now we will start off simple.

Now that we have our default skeleton, you can load the converted .UMF scene (from the example provided in the members area or one just bought).

Default skeleton (blue) and Stockmoves hierarchy (yellow)

If you have trouble converting the .UMF file into a scene file, please have a look at the previous tutorials.

1.2 Constraining the hips

What we are going to do is constrain our default skeleton to the Stockmoves data in such a way that it follows the movements of our Stockmoves hierarchy.

Before we can start constraining we need to match up the sizes of the Stockmoves hierarchy and the default skeleton. So pick up the default skeleton in branch mode and place it so the position of the root of the spine matches up with the first lowest joint of the spine of the Stockmoves hierarchy.

Positions matched

Now we can scale the default skeleton down so it matches up with the size of the Stockmoves hierarchy. Watch the shoulders and the hips for a good indication. Don't forget to freeze the scaling of the skeleton after you're done to avoid any problems later on.

Scaling matched

The easiest place to start constraining is with the hips.Go in and select the root of the spine from the default skeleton (not the root of the whole skeleton but the root of the chain that makes up the spine).

The root of spine selected

Do a position constraint to the lowest spine element from the Stockmoves hierarchy. If you look at the picture below, what you need to do is constrain the white element to the red element. Scrub or play the animation to check if the skeleton is moving like it should.

Constraining the root of the spine (white) to the first Stockmoves spine element (red)

1.3 Constraining the spine & head

OK, now we have the whole skeleton moving but it's still as stiff as a stick.We will need to continue on with the spine elements.

Perform an orientation constraint (in some packages it's called rotation constraint) with the first bone of the spine of the default skeleton to the first element of the spine of the Stockmoves hierarchy.

Constraining the first spine element

Continue with constraining the second bone of the spine to the second spine element of the Stockmoves hierarchy.

Constraining the second spine element

And while we're at it, orientation or rotation constrain the neck and head bones to the corresponding Stockmoves elements.

Constraining the neck and head

When you now play or scrub the animation, you should have the upper body of the character moving like it should.

The spine, neck and head constrained
play movie (mpg - 145 kb)

1.4 Constraining the arms

The next thing on our list is the arms. Start by orientation or rotation constraining the upper arm bones to the upper arm elements of the Stockmoves hierarchy.

Constraining the upper arms

Continue on with the lower arms and finally the hands.

Constraining the lower arms

Constraining the hands

Play the animation in loop mode for a while now.

The arms and hands constrained
play movie (mpg- 145 kb)

What you can see is that the rotation of the arms is pretty much there.But you can also see that the up and down, front and back motion of the collar bone area is not taken into account.This could be all right if the 3D character that is riding on this skeleton has a rigid look in the shoulder area.But if the character is made out of flesh, it's usually desirable to have the collar bone motion applied as well.

In order to do that we have to position constraint the roots of the arm-elements to the upper arm elements of the Stockmoves data.

Constraining the collar bones

When you've done this, loop-play the animation and you will notice a much more fluid and natural motion in the shoulder area.

The collar bones constrained
play movie (mpg - 145 kb)

1.5 Constraining the legs

Now that we have done the arms, it shouldn't be too difficult to do the legs.Let's dive right in.

Orientation or rotation constraint the upper leg bones to the upper leg Stockmoves elements. Also orientation or rotation constraint the lower leg bones to the lower leg Stockmoves elements.

Constraining the upper legs

Constraining the lower legs

For the the feet you will notice that the Stockmoves hierarchy only uses one element for the feet and the default skeleton uses one element for the foot and one for the toes.

What we'll do is orientation or rotation constrain the first bone of the foot to the foot element in the Stockmoves hierarchy. You can later go in and keyframe the toe elements manually by placing rotation keyframes on them, or use expressions to control them.

Constraining the feet

The last thing we need to do is similar to what we did with the collars.We need to position constrain the roots of the legs of the default skeleton to the upper leg elements of the Stockmoves hierarchy.

Position constraining the legs

Congratulations!You should now have a hierarchy that's moving like the Stockmoves data that you blended with the client software. The next chapter we'll get more in depth and show you examples on how to make offsets, scale different bones if your character has different proportions compared to the Stockmoves skeleton, and it we'll also show you what to do if you want to use another setup for the spine and forearms.

The skeleton fully constrained
play movie (mpg - 145 kb)

What you can do now is either hide the Stockmoves hierarchy and leave it in your scene, or plot the rotations of all the bones and the positions of the roots of the arms, legs and the spine, and then delete the Stockmoves hierarchy. You can also start to load or create geometry and place that on the bones by either parenting, enveloping, or skinning it.

Chapter 2 Advanced Techniques