In the next steps, you’ll learn how joints and skin weights influence deformations on Sven's torso. In a subsequent section, you’ll improve uneven deformations.
To see how skin weights affect a skin’s deformation
- Pose the left arm similar to the following figure. The side of the torso compresses in the pose.
- Select sven_body.
- Select
Skin > Paint Skin Weights >
.
-
In the
Influences list of the
Tool Settings window, select a random joint.
The grayscale color of Sven’s skin indicates how much influence the selected joint has on the skin deformation. In general, a white region of skin is influenced nearly entirely by the selected joint. A gray region is influenced significantly by one or two additional joints, and a black region indicates skin not influenced by the selected joint at all.
Tip:If you prefer, you can turn on Use Color Ramp in the Gradient section of the Paint Skin Weights Tool to view the influence feedback in color. This can make it easier to see small weights. For the rest of this lesson's images, color ramp will be on.
Each point on Sven's surface is influenced by three joints, as specified by the Max Influence setting in a prior step. However, one or two of the three joints might have so little influence as to be insignificant.
In this case, the torso becoming irregularly shaped as you pose the left arm indicates that one or more of the joints is exerting too much or too little influence on the surface. In the next steps, you will determine which joints are influencing the irregular region.
- Do the following to select the vertices in the problem area:
- In the Paint Skin Weights Tool, turn on Paint Select mode (below the Influences list).
- Right-click Sven's skin and select Vertex from the marking menu.
- Paint to select the vertices around Sven's underarm.
- In the
Paint Skin Weights Tool, click the
Show Influences
button.
All joints that influence the selected vertices are selected in the Influences list.
Tip:If you don’t immediately see the selected influences in the list, scroll to find which influences are selected.
Depending on which vertices you selected, the Influences list shows you that the main joints influencing this region are from the mid and upper back, and the left arm.
- Now that you have narrowed down which joints are influencing the leg, select each entry in the
Influences list individually to view the shades of gray on Sven’s skin.
The left_shoulder is the main influence. The upper_back, mid_back, and left_arm_root also have influence, though not exactly in the same region.