What is the difference between drawing frames and keyframes?

In Harmony, drawing frames and keyframes are both equally important when it comes to animation, however this doesn’t mean that they are the same. In fact, these elements have very different properties and knowing how and where to use them is fundamental to animating in Harmony.

What is a drawing frame?

A drawing frame is a single frame of artwork that can only be found on a drawing layer. Every drawing layer with artwork on it will have at least one frame, usually represented by one or many grey blocks. Only drawing layers allow for drawing frames, these layers are represented by a shape icon on the Timeline.

What are the properties of a drawing frame?

The following properties apply to drawings frames:

• Drawing frames only hold artwork information. Placement and exposure is adjusted by the user.
• A drawing frame is created when the user manually adds one, or when a drawing tool is used on an empty frame.
• Each drawing frame is saved in the scene’s files as a TVG, which can be recalled from Harmony’s substitution library using its unique ID.
• Copying and pasting drawing frames on the Timeline will automatically recall the image from the library. Editing this image will edit all frames with the same ID. Frames must be duplicated to create a new ID and allow for editing.
• Drawing frames can have keyframes placed on them. When no keyframes are being used, movement is created purely by the placement of drawings.

How are drawing frames used?

Drawing frames can only contain static artwork. They can be used for the following:

• Frame by frame paperless animation
• Character, background and prop designs
• Artwork and substitution drawings used in rigs
• Matte layers used for effects

What tools can be used to create drawing frames?

The following tools can be used to create drawing frames and their artwork:

• In the Timeline toolbar, Create Empty Drawing and Duplicate Drawing can be used to create new frames.

  

• All drawing tools found in the Tools toolbar can be used to create or edit artwork on a drawing frame.

• You can also use keyframe tools (see below) to set keys and interpolations on drawing layers, though it is not recommended.

What is a keyframe?

A keyframe is an indicator that can be found on many types of layers. It can be used directly on a drawing frame, or on specific layers that allow for transformation but contain no art. A keyframe indicates that the transformation on a specific frame is saved. An interpolation can be added between keyframes to create fluidity.

Keyframes are represented by solid black and red, and sometimes white, dots on the Timeline. Interpolations appear as black lines linking the keyframes.

What are the properties of a keyframe?

The following properties apply to keyframes:

• Keyframes cannot hold any artwork information, they record the transformation values on the current frame. This transformation is applied using the animation tools and holds values for scale, rotation, position and easing.
• Keyframes are not linked to the element folders or the substitution library. 
• Editing a pose on a copied and pasted keyframe will not edit the original.
• Inbetweens can be created using interpolations.

What elements allow for the use of keyframe animation?

The following layers allow for the creation of keyframes and interpolations:

• Drawing layers
• All transformation type nodes (Pegs, deformers, constraints, timing nodes, etc.)
• Effect functions that allow for value animation

Keyframe animation is largely used in cut-out animation, where the rigged characters have a mixture of drawing and transformation layers.

What tools can be used to create keyframes?

The following tools can be used to create keyframes and interpolations:

• Animate Current Frame must be activated to allow for the automatic creation and saving of keyframe information. 
• The Transform tool in the Tools toolbar for general transformation of all aspects (scale, rotate, position).
• The tools in the Advanced Animation toolbar.

• The ease and interpolation tools in the Timeline toolbar.

About keyframes on drawing frames

Because drawing frames and keyframes hold different information, they can be used together on the same layer. Keyframes can record applied transformations while drawing frames hold the artwork.

While this is suitable for beginners and very simple animation applications, it is not recommended for anything that requires any type of hierarchy or complex animation.

What issues can it cause?

Applying keyframes directly to drawing layers can cause the following problems:

• Keyframes and drawing frames can be harder to manipulate separately on the Timeline when they share the same frame space.
• If your drawing layer is connected to a transformation layer like a peg, the keyframes on the peg layer can conflict with those on the drawing layer. This is especially a problem in rigs.
• If you want to use the transformation of the keyframes on the drawing layer on another layer, parenting and Node view setup can become cumbersome.

What is recommended?

The following tips are recommended when you want to use drawing frames and keyframes:

• Add a peg to the drawing layer and apply your keyframes and interpolations on this layer. For more information, see Adding Pegs.
• Deactivate the Element Node ”Animate Using Animation Tools” Default Value preference. For more information, see How can I prevent keyframes from being set on drawing layers?