INSIDE 3DS MAX® 7 [Electronic resources] نسخه متنی

Skin Morph Modifier

When a realistic character bends its arm, the deformation is complex. The overall volume stays the same, but the biceps bulges, the triceps stretches out, and the skin creases and flattens at the inner elbow. Getting just the right creases, and eliminating unwanted ones, has always been a time-consuming process in 3ds max, because the program does not have a native muscle deformation system that could handle this automatically. Creating good-looking deformations therefore has required much complicated interaction with the Skin Modifier.

This process has been simplified with the new Skin Morph modifier. With it, you can fine-tune your animations using bones to drive corrective morphs around problem creases and bulges. In essence, the Skin Morph modifier allows you to quickly build simple versions of a muscle system. For example, in the case of our bending, bulging arm, you would set the model to deform when a child bone (the forearm) is at a specified angle to its parent (the upper arm bone). The arm's mesh will deform back and forth every time this angular relationship is animated with the Skin Morph modifier applied over the Skin modifier.

Let's take a closer look at Skin Morph, available from the Modifier's list. Start by applying the Skin Morph modifier to your object or character. (We are using the Deviled Egg character for this discussion.) Check Beginner mode and create a morph on the desired angle change of the bones (Figure 4.15). Note that bones must be added in the Parameters rollout to see them in the list.

The Skin Morph modifier has a sub-object level for editing points. Changes made to the points are recorded based on the bone angle change. Every time the bone is at its recorded angle, it causes those points to deform. The Influence Angle parameter is set for each morph. Use as small an Influence Angle as possible to prevent multiple morphs from influencing one another (Figure 4.16).

Note that when Beginner mode is unchecked, 3ds max 7 creates morphs automatically and without requiring you to click the Create Morph button.

Animate the forearm vertices of the Deviled Egg, and they deform according to where you moved the points (Figure 4.17).