Tutorial 7: Skinning with Physique

Lesson 3: Adjusting Envelopes and Weighted Vertices

The bulk of the work in Physique is adjusting the size and overlap of all the envelopes to fine-tune mesh behavior as the character moves. Each area of the mesh requires some thought.

As you adjust the envelopes, scrub the time slider and rotate a User viewport. Moving a character reveals different flaws in the mesh as the biped posture changes in the animation.

Tip: While adjusting envelopes, you can use In Place mode on the Motion panel General rollout. In Place mode keeps the character in a viewport at any frame of the animation by limiting center of mass motion about the XY axes.

After attaching the mesh to the biped with Physique and loading the animation, parts of the mesh seem to stretch off the body. Vertices that are not within envelopes remain in their original positions and create stretched polygons. Roughly adjust the radial scale of the envelopes to pull in these vertices and then begin the process of fine-tuning the envelopes. For example, vertices on the mesh fingers may not be covered by envelopes creating the stretched polygons when animation is loaded.


Continue where you left off with Tut_DrX_02.max, or load Tut_DrX_03.max. Files for this tutorial are in the cstudio\tutorials\tutorial_7 under your 3DS MAX directory.

Loading a motion file

  1. Select the biped.

  2. On the Motion panel, on the General rollout, turn off Figure mode.

  3. The character adopts an animated position. The envelopes need work.

Adjusting the envelopes

  1. Select the mesh.

  2. On the Modify panel, on the Physique Level of Detail rollout, turn on Hide Attached Nodes.

    The biped disappears and you have a better view of the mesh.

  3. Scrub the Time Slider to frame 27, the left hand is up in the air.

  4. At frame 27 turn on Sub-Object Envelopes on the Physique modifier.

  5. Enlarge the Front Viewport and zoom in on the left hand.

  6. Select the forearm, palm, finger and thumb links in turn. Change the Radial Scale and Parent\Child overlap until the distortions of the mesh disappear.

  7. Scrub to frame 51, the right hand is in the air.

  8. At frame 51 on the right arm, select the links of the forearm, hand, and fingers in turn. Change Radial Scale and Parent\Child overlap until the distortions of the mesh disappear.

    Because of the ponytail link there are two links in the head. You must turn off the link that does not continue to the ponytails.

  9. Select the link that does not continue to the pony tails, on the Blending Envelopes rollout in the Active Blending area, turn off Deformable.

  10. Select the head link that continues to the ponytail and change it to a rigid envelope. Turn off Deformable and turn on Rigid.

  11. Scale up the rigid envelope until the character's face and nose are not deformed.

    The face should not twist when the character rotates his head. This is the reason for using a rigid envelope in the head.

  12. Scale and change the parent\child overlap of the ponytail links to smooth out this area.

  13. At frame 51 adjust the envelopes of the feet so the shoes are not deformed.

    If you must scale the feet envelopes to the point that one foot's envelope deforms the opposite foot, turn on Control Point in the Selection Level area and move the envelope control points to correct deformation.

    Tip: Try turning on Initial Skeleton Pose in the Blending Envelopes rollout in Sub-Object Envelopes for a clear view of the envelopes. To see how much of the mesh is encompassed by an envelope, see if Initial Skeleton Pose is turned on.

  14. Save your work as a .max file.