Adding target objects to an existing blend shape
 
 
 

In the next steps, you duplicate the face again and reshape the duplicate into a new facial expression. You then add the new face to the blend shape node to create another slider in the Blend Shape Editor.

To create another facial expression

  1. Set the Blend Shape editor slider value to 0 to return baseFace to the position it had at the beginning of the lesson.
  2. Make a duplicate of baseFace, name it raisedBrow, and move it to the left of baseFace so that all three faces are visible for comparison.

  3. Make sure raisedBrow is selected.
  4. In the perspective view, select Show > Isolate Select > View Selected. Select this menu item again in the front view.

    This displays only the selected object (raisedBrow) in the views. This is necessary to avoid selecting unwanted vertices in the next steps. The view’s label indicates isolate is turned on.

  5. In the front view, position the pointer over the face, right-click and select Vertex. Drag a selection box around the vertices in the region of the eyebrows and forehead as shown below.

    For these vertices, you need to select the vertices by dragging a selection box rather than by using the Paint Selection Tool. The eyebrows have vertices that lie behind its outer surface. The Paint Selection Tool selects only vertices at the outer surface. Dragging a selection box selects all vertices in the boxed region, including vertices that lie behind the outer surface.

  6. In the side view, hold down the Ctrl (Windows and Linux) or Control (Mac OS X) key and drag a selection box around the vertices at the side of the head to turn off their selection (see the following figure).

  7. Switch to wireframe display mode and dolly the camera from various close-up views to make sure you select all the vertices on and under the eyebrow. If you miss a few vertices, subsequent deformations will not work correctly. Also, make sure you don’t select vertices at the side or back of the head.
  8. Select Create Deformers > Cluster.
  9. In the perspective view, turn off the selection of Show > Isolate Select > View Selected. Do this again in the front view.

    By turning off these menu selections, Maya displays all objects in the views again.

  10. In the perspective view, drag the cluster up along its Y-axis a small amount until raisedBrow looks like the face on the left:

To add the new target object to the blend shape

  1. In the Outliner, select raisedBrow and Shift-select baseFace (the order of selection is important). The raisedBrow is the target, while baseFace is the base object.
  2. Select Edit Deformers > Blend Shape > Add > . In the options window, turn on Specify Node and enter blendShape in the BlendShape Node box. Click the Apply and Close button.

    When you created the blend shape for the smile, Maya created a node named blendShape that contains the slider attributes that adjust the blend into the smilingFace target. The Add operation creates a blend shape for the raisedBrow and adds it to the blendShape node. This adds a slider to the node’s Blend Shape editor for adjusting the raised brow deformations.

  3. To display the Blend Shape editor, select Window > Animation Editors > Blend Shape.

  4. You can use the sliders alone or in combination to create a smile with raised eyebrows, a frown with lowered eyebrows, and so on.

  5. You can optionally select raisedBrow and edit the cluster weights to tune the deformation of the eyebrow region as desired. See Editing cluster weights for details. An example weighting follows:

    TipAfter you create a blend shape, you can optionally hide or delete a target object (in this lesson, smilingFace and raisedBrow). If you delete a target, you improve Maya processing time but lose the capability to manipulate the cluster handle. For versatility, many animators hide the target rather than delete it. Hiding the target is necessary when you render the scene. It is also useful when you want to unclutter the scene view.