Using Squash 'n' Stretch

Squash ’n’ Stretch is an optional algorithm that allows the inverse kinematics and retargeting solvers to automatically lengthen and shorten your character’s arms, legs, spine and neck when attempting to place the character’s Nodes at their goal points.

With conservative settings, Squash ’n’ Stretch gives your characters a small amout of extra flexibility, which can add an extra level of dynamic appeal and realism to your animations. For example, as a character bends backward to avoid a projectile, its spine can lengthen slightly before snapping back to its original length as the character straightens up.
With more extreme settings, Squash ’n’ Stretch can also produce more cartoony, bouncing effects. For example, during a walk cycle each of the character’s legs could stretch as it extends, then squash back to its regular proportions as the character puts its weight on the leg.
During retargeting, Squash ’n’ Stretch may help the target character’s limbs match the angular configuration of the source character. This can help preserve the feel of the source animation. For example, when retargeting from a character with long arms to a character with short arms, a bent elbow in the source animation would normally have to be extended in order to have the target character’s hands match the source character’s. However, with Squash ’n’ Stretch, the arm can stretch a little in length to reduce the amount of change needed in the bend angle of the elbow.
Squash ’n’ Stretch also helps to avoid the noticeable "popping" that can occur when a character’s arms and legs reach their full extension.

You can enable and configure Squash ’n’ Stretch separately for your character’s arms, legs, spine and neck.

Setting up Squash 'n' Stretch

Using Squash 'n' Stretch

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