Thinking Outside the Box:
Character Studio (part 2)

By Paul "Villam" Steed

Now think of the tags as representations of, or placeholders for those distinct body parts. Thus the tag at the base of the neck is called ‘tag_head’ to represent the head and the tag at the waist is ‘tag_torso’ to represent the upper body. In a top view the actual tag would look something like this…

Make sure its orientation and look is relatively the same. Now look at the following…

This diagram illustrates how I place the tags in relation to the biped itself. Since the tags represent the transform pivot point of the area of the body they represent, placement is important in relation to the biped body parts. In this illustration you can see their exact location…

Note that the tag_torso is right at the pivot point of the biped’s first Spine. The tag_head is at the juncture of the neck where the head meets. The geometry supports both tag points by intersecting appropriately (torso has curved geometry at the bottom and the neck is a curved stump). I normally try and play around with the geometry, rotating the intersecting pieces to see how they look. Be forewarned that it takes some thought and planning to make your meshes support this scheme.

Back to Physique. Go ahead and select the arms and torso of the object and apply Physique to them. It’s perfectly fine to assign Physique separately to each object, but we can still select an object like the left arm and tweak its physique attributes individually by just selecting it alone. The convenient thing about assigning a modifier to more than one object is that it can be deleted or affected across the board with one mouse click if necessary. Click on ‘Attach to Node’ and initialize with the default settings clicking on the Spine.

Now this is where I should explain in detail when you use the default settings of Physique and when you change to something else. Sorry. Read the manual. Seriously though, most of the time I just let it do its thing because I can always go into the vertex sub-menu of Physique and assign individual vertices with whatever rigid or deformable attributes I want. Wait a minute...What the heck! Let’s just go ahead and do that now! (How’s that for a segue…)

Select just the torso.

Now go to the vertex sub-object menu under Physique. Notice how the little stick arms of the Physique linking structure is visible even though we didn’t pick the arms. This is because even if we had not assigned the modifier to all three objects simultaneously, the arm links would still exist since the Spine is the parent of everything comprising the upper body. Now ‘Select’ is already selected under the vertex sub-object menu so go ahead and drag a box around the vertices below the neck of the torso.

Note that the verts selected are different colors – red and burgundy. Red verts mean that they are assigned to a link or bone but are also influenced by other links or bones directly above or directly below the link to which they are assigned. Now the burgundy ones are different. They are basically assigned to no particular link per se but have been caught in the middle between more than one link (well they have, but they may as well not have given the amount of influence that can be exerted on it from elsewhere). This gives them all kinds of movement as they haven’t quite committed to any one link. Let’s go ahead and change that.

Since the upper body represents an armored, almost carapace-like physiognomy we can make these vertices rigid and unbending with their parent being the main spine link. The reason why we do this is that if the verts are assigned to different parts of the spine up the spinal chain, a torquing or shearing would take place and detract from the hard armored look. Sooo….

With the verts still selected go over to the command panel and click on the arrow beside ‘N Links’ and choose ‘No Blending’ instead.

Next click on ‘Assign to Link’…

…then click the green cross at the top of the sub-menu under ‘Vertex Type’…

…and click on the Spine link on your mesh thus assigning all those vertices to the first joint in the spine chain.

The last step you have to remember to do when manually assigning vertices is to lock them to that link with the ‘Lock Assignment’ button…

You know this is accomplished because tiny boxes appear around the vertices. This is really useful since even if you’re going through the mesh and select the locked verts by accident, they won’t be affected unless you ‘Unlock Assignments’ first. You can also play around with typing in the weight of vertices with the ‘Type-In Weights’ button, but only if those vertices have locked beforehand. Also remember that you can hide vertices if the mesh gets too confusing and unhide them when you’re done tweaking.

(Continued on next page)