How to Use Deformers

Deformers give the ability to animate objects and parts of a character model using computer generated deformations. This allows you to bend or distort drawings without having to redraw them. When used in cut-out animation, they can extend considerably the range of movements and poses a character model can pull without having any of its parts drawn in different poses, which can save a lot of time and make your cut-out animation look much more natural with little effort.

Deformers can be used to deform a single drawing layer or a hierarchy of layers, so a single deformer can be used to deform anything ranging from a simple prop to a whole character rig.

Deformers work by rigging them as a parent drawing(s) you wish to deform, building the deformer structure, then animating it. This can be easily done using the Rigging tool.

There are two types of deformers available in Harmony Essentials:

  • Bone
  • Game Bone
NOTE: Harmony Premium also supports Curve and Envelope deformers, which offer extended deformation capabilities that are not supported in Harmony Essentials.

Bone Deformer

The Bone deformation allows you to create a bone-like structure in which each part is solid, but with articulations that are flexible. This is mostly useful for animating a character's limbs, such as the arms or legs, or other parts that can be articulated such as torsos or fingers. For example, a Bone deformation can be used to articulate an arm that is made of a single drawing, so that the upper arm and forearm can be moved independently, without having to draw the upper arm and the forearm on different layers. Harmony will deform the drawing to make it look articulated. The different parts of a Bone deformation can be rotated around their joint, extended and shortened, giving you the same capabilities as animating articulations on different layers, without having to worry about parts detaching, pivot points, or clipping outlines.

Game Bone Deformer

The Game Bone deformation is very similar to the Bone deformation. It allows you to create a bone-like structure in which each part is solid, but with articulations that are flexible. However, it is optimized for game engines such as Unity. Hence, it is usually only used for game development and not in animated productions. Contrary to the Bone deformations, Game Bone deformations do not have a Bias property. The articulation folds also look slightly more rounded.

Creating Deformers

The most simple way of creating deformers is to use the Rigging tool, available in the Deformation toolbar. With this tool, all you need to do to create a deformer is to select the layer you wish to deform, then place each point of your deformer in the Camera view.

A deformer is a hierarchy of its own. When you create a new deformer, the first point you set is the deformer's root, and each new point you create is a child of the previous point. Deformers are hence created in a chain, and should be created with your character's hierarchy in mind. For example, when you create a deformer for an arm, the root should be the shoulder joint, the second point should be the elbow and the third should be the wrist.

When you create a new point using the Rigging tool, it is created as a child of the selected point. This is essentially how the Rigging tool knows if it's creating a new deformer, or building an existing deformer, as the last point you created will be selected by default. But you can also use this mechanism to create deformers that split into multiple chains, by selecting the point in the middle of an existing deformer, and building a new chain from there.

NOTE: You can also use the Timeline's Insert menu to manually add the nodes necessary to create your deformation structures.

Displaying Existing Deformation Chains

Harmony lets you control which deformers are displayed in the Camera view independently from the current selection. When you create a deformation chain, its deformation controls are displayed in the Camera view. However, if you select an existing deformer or a layer that's connected to existing deformers, its deformation controls won't display right away. Likewise, deselecting a deformation chain will not hide its deformation controls. Before you can animate or modify an existing deformation chain, you must manually display it.

Modifying Existing Deformation Chains

As you attempt to animate a deformation, or if you need to make changes to the drawings under a deformation, you may need to make adjustments to the deformation chain to better fit your needs.

NOTE: When using the Rigging tool, you can select which existing deformation point you want the next deformation point you create to branch from at any time by selecting a point in the Camera view. When you create a deformation point with the Rigging tool, it is always linked to the currently selected deformation point. By default, creating a deformation point makes it selected, which is why you don't need to select it to create a simple deformation chain. If no deformation point is selected, the Rigging tool creates a new deformation chain

Animating With Deformers

Just like with animating pegs and drawing layers, you can animate your deformers by creating keyframes on their corresponding layers in the Timeline. Animating deformers works exactly like making modifications to a deformer, except it requires using Transform tool instead of the Rigging tool. When the Transform tool is selected, deformation controls in the Camera view display in green, which means they are in animation mode, whereas when the Rigging tool is selected, they display in red, meaning they are in rigging mode.