[Public] Art Tip: Boomerang vs Cyclical Loops (Patreon)

Boomerang and Cyclical loops are two ways in which you can make animation loops. This often applies to NSFW animations, which involves repetitive motions.

In this quick lesson, I’ll break down the difference between the two.

Boomerang Loop

I’m not sure if there’s a real technical term for this, but I named it after the boomerang feature in instagram.

Basically, it’s a back-and-forth motion, so the motion goes one way, reverses back, and repeats. Technically not a true loop.

Pros:

• Fewer frames, therefore less work, can be good for simpler animations
• Doesn’t require thinking about looping the motion since it’s not a true loop

Cons:

• Movement can look clunky and un-lifelike, especially when there’s a lot of moving parts.
• Doesn’t allow you to use certain animation techniques (e.g. the anticipation-overshoot-settle cycle)
• Doesn’t allow you to place elements that only move in one direction in time. For example: certain bodily fluids flowing down.
• Many other things can’t be done with a boomerang loop but are possible with the cyclical loop.

In general, boomerang loops are simpler, but it has a lot of drawbacks, which is the reason I tend to recommend doing cyclical loops instead. The only exception is shitposts, in which case just do whatever’s easier lmao

Cyclical Loop

This one is a linear progression of frames (not back-and-forth), where the last frame loops back to the first frame.

Pros:

• Allows for very lifelike motion.
• Supports all of the basic animation techniques, especially the anticipation-overshoot-settle cycle, which comes in handy in nsfw animations
• Can place elements like fluids flowing down very easily.
• Allows for many other things. Such as...
  
  ...butt jiggle.
• Need I say more?

Cons:

• Usually requires more frames, therefore more work.
• Requires more thought and planning to make the looping look good and not awkward.

Cyclical loops are the ones used in professional works, especially in games. A character’s walking, running, and even idle animations will always be cyclical loops.

Here’s an example featuring a beloved character, Beowulf from Skullgirls

It might look like he’s moving back and forth, but if you pay close attention to the individual parts, like the hands for example, it’s moving in a cyclical loop, i.e. none of the movements are repeated in reverse.

Another example is the sprite work from Scott Pilgrim vs The World the Game

This one is a lot clearer to see because his head and fists are literally moving in a circular cycle, and it creates a very energetic and lively motion.

Summary

If you want to do animations in any capacity, definitely look into cyclical loops and avoid boomerang loops whenever you can.

I’m not an expert animator, and I don’t consider animation my primary genre, so here are a couple of recommendations for further reading:

• 12 Principles of Animation illustrated by Alan Becker (creator of Animator vs Animation): https://www.youtube.com/watch?v=uDqjIdI4bF4
• Animation Tips by Toniko Pantoja: https://www.tonikopantoja.com/tips

ADDENDUM 1: It's Not about the Number of Frames!

The reason Cyclical loops are better than Boomerangs has nothing to do with the number of frames! Even when the cyclical loop has significantly fewer frames (and a lower framerate), it still tends to look more life-like.

The key is that the Cyclical Loop does not replay frames backwards. Time is linear IRL, so an animation made with linear time progression will naturally look more lifelike compared to one made with a back-and-forth time progression.

Although, it's also true that with Cyclical Loops (provided you map out the movement properly), the more frames you add, the smoother and better it becomes.  

The opposite is true for boomerangs. The more frames added, the clunkier / jankier it tends to become.

ADDENDUM 2: Motion Lines and Effects

Simply put, motion lines just never looks natural on Boomerang loops, but it fits right in with Cyclical loops.

Bonus!

Patrons have access to the extended lesson for creating an Animation Loop, which includes more nitty-gritty details like mapping out motion, time lag, etc.

https://www.patreon.com/posts/lesson-animation-54545528