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Follow Through & Overlapping Action

Guide info

Short: 3-5 minutes

TLDR - What this guide covers

  • Follow Through shows how different parts of an object are affected by inertia.
  • Overlapping Action shows how loosely connected objects move at their own individual speeds to make organic movements.
  • These principles are much more applicable for exaggerating weight on organic objects as opposed to rigid, heavy, and mechanical objects.

1: Follow Through

As the name suggests, Follow Through outlines how __ even when an object stops moving, some of its parts continue moving before gradually coming to a stop.__ This principle best resembles Newton’s first law of motion: an object remains moving until an external force acts on it. Let’s visualize this by comparing two examples:

Without Follow Through

In this example, the car and the driver stop moving at the same time, making the motion feel unnatural. The driver is merely sitting in the car, so we intuitively expect them to keep moving slightly after the car stops due to how loosely connected they are even with seatbelts.

With Follow Through

By applying Follow Through, the driver gains a slight movement after the car stops, making the movement feel more natural. The added motion mimics real-world physics, revitalizing the animation.

Additionally, we can also see Follow Through in full display through this animation by TArrow.

Here, the blue stick figure’s lower body continues moving even after its head is forcefully stopped by the giant, contrasting how different they are in terms of strength, weight, and durability.

Uses of Follow Through

Follow Through enhances animation believability by conveying weight and inertia. It is especially useful in bossfights, making their movements feel grounded and realistic.

However, excessive Follow Through can make certain objects feel inorganic. Too much inertia on heavy objects makes them unnatural. In the previous examples the objects were loosely connected, and therefore had lots of inertia, but heavy objects that have a strong link don’t need as much. Additionally, unnecessary Follow Through on background elements can distract players from focal points.

2: Overlapping Action

Overlapping Action is similar to Follow Through but focuses on how parts of an object inherently move at different rates.

Without Overlapping Action

When every part of an object moves simultaneously, the motion appears robotic or rigid. This is useful for metallic or mechanical objects, such as vehicles, but it can break immersion if applied to organic elements, such as a dog’s movement.

With Overlapping Action

Notice how the dog’s ears and tail move differently relative to the head. Structurally, those parts would have a flimsier bone structure than the skull. Being mindful with these details help to make animations look more natural.

A great example is found in the dragon’s movements in Against the God by 1374.

This is a strong example of Overlapping Action as the dragon’s limbs arc with different timings as it flaps its wings. Additionally, notice how the wingtips move faster than the rest of the dragon’s wings. This is because its main action starts from the shoulders then cascades to its wingtips to fly.

Uses of Overlapping Action

Using Overlapping Action works with Follow Through to create visual interest and give movements personality and purpose. It’s used to offset the individual speed of an object’s limbs to mimic organic movement.

It shouldn’t be used in objects you want to provide a sense of rigidity with, like metal or stone blocks, as Overlapping Action brings elasticity to your objects. These types of objects aren’t organic, so they should move stiffly instead. They should also be rarely used in snappy movements, since all parts of a moving object move so fast they appear to move simultaneously.

Sources

Credits

Created by @Sandboxer and @Selena

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