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A Game Art Trick
The High Heel Problem

Introduction

This article looks at how different types of shoes can affect game development and examines how games deal with this in practice.

Before we dive in, let’s have a look what’s possible with high heels:

Sources: #1 #2 #3 #4 #5

Just in case I mess up the terminology, here is a little chart:

Source: Shola

Character Height | Posture | Animation | Optimization | Audio | Bonus | Summary | Sources

💘💘💘 Huge thanks to Nicolas, Damrus, Irina, Battz, Magari, Luna, Angel for helping with this article. 💘💘💘

Character Height

🚨 The Problem

Different character body sizes mean a lot of extra work for game developers. Here’s a great example for Dragons Dogma 2, where characters with different body sizes still manage to kiss:

Source: Dragons Dogma 2 Let’s Play #1 & #2

Here we can see how the animation is adjusted so that the lips can meet. The camera also does a lot of work:

Source: Dragons Dogma 2 Let’s Play #1 & #2

But even if all characters have the same height, different shoes can influence the height of a character as well! This results in new bone positions, so that, for example, a finger no longer hits a button on the wall.

Source: Mixamo “Romero”

Apart from precise interactions, there may be other special cases in which heels could lead to a problem: For example, you should be careful that heels do not give the player away behind cover:

Source: Mixamo “Romero”

If the character’s height changes, you may also need to update the hit collision volumes – especially in competitive games. This depends on how the engine handles such volumes. Better double-check!

Game developers are now on a cross road. Choose wisely!

Let’s talk about option A first, where we adjust the height of the character correctly and realistically!

💡 Solution A: “Adjust Height”

There are three ways to deal with the consequences of the characters’ different shoe heights:

  1. Hope for the best
  2. Fix Manually
  3. Fix Dynamically

🙈 1. Hope for the best

Some games can afford to adjust the character height because there are only few precise interactions with NPCs or the environment. When playing Infinity Nikki, for example, I mostly found animations where it doesn’t matter whether Nikki is 10cm taller or shorter (like opening a chest):

Source: Infinity Nikki

And I can’t remember any precise interaction in the cutscenes either (e.g. a handshake). So, raising the body is not much of an issue:

Source: Infinity Nikki

However, there is one exception: I have noticed a situation in which there is close interaction: Grooming. There are two outfits for this: one with and one without heels:

Source: Infinity Nikki

I think if I look very closely, I can see that there is a slight clipping problem with the animation with heels. Could be due to the different terrain though. I’m not sure, but it’s definitely not a big deal.

Saints Row is another game that correctly resizes the character, and it’s the only game I’ve stumbled across where you can wear heels as a male character:

Source: Saints Row

💪 2. Manual Labor

If the game needs it, animators could create unique animations (per shoe type) where e.g. the hand positions are corrected. They will love it!

stand_groom_barefoot.fbx
stand_groom_shoe_5cm.fbx
stand_groom_shoe_12cm.fbx

But be careful! If not all animations are adapted, this can lead to problems. Here, for example, a specific golf animation only seems to be available for flat shoes:

Source: GTA Online

The same happens with the drinking animation (right), which only seems to be available for flat shoes. Special cases such as motorcycling also require special attention when heels are involved:

Source: Suggestions to improve female characters

Here’s a closer look at what happens: The feet have to strike a different pose when high heels are worn (right). Otherwise it looks funny (left):

Source: CGarchitect

Incidentally, the same behavior can also be seen in Nikki for a single frame when the shoes are swapped. The shoe mesh is replaced one frame before the pose adjusts:

Source: Infinity Nikki

⚙️ 3. Dynamic Systems

Manual adjustment is a lot of work! Isn’t there a way to automate this? For example, it would be a nightmare if you wanted to have a hand-holding mechanic and then you need tons of animations to make sure that the hands of characters with different shoe heights still meet precisely.

Source: Hand Holding Mechanics

IK to the rescue!

Modern engines offer real-time IK systems. Most players are already familiar with them, as these systems adapt the foot orientation to the terrain:

Source: Infinity Nikki

Such systems can also be used for atmospheric procedural animations such as touching a wall as you walk by:

Source: iHeartGameDev | Uncharted

Or, and this is particularly exciting for our topic, to dynamically adjust the hand position in the direction of a target, so that the character itself can have a different height and/or the target can be at a dynamic height in the level:

Source: Unreal Content Examples: IK Rig

But be careful. If the IK target is not used correctly, you may end up with NSFW animations. You have been warned!

💡 Solution B: “Find Workaround”

Don’t want to manually adjust all animations or use a dynamic system? No problem!
Let’s take a look at some ways to equip characters with high heels without changing the actual body height to get around the things mentioned above.

Again, we have three options:

  1. Hide
  2. Shorten
  3. Bend

🙈 1. Hide!

If the shoe allows it, you can “hide” your feet in the soles. This makes the leg look shorter (just like in the next section) but neither the leg nor the shoe needs to be altered:

Source: Example kindly provided by Irina

🦶 2. Shorten

I have seen this solution very often in my research: The lower leg is simply shortened so as not to change the height of the character.

Here is an example in Sims 4, as you can see: The hip stays in place, the upper leg doesn’t change, but the lower leg is shortened (the angle is moved up):

Source: Sims 4

Another example while seated:

Source: Sims 4

The same in Watchdog Legions. However, the shape of the lower leg changes here as it is slightly compressed:

Source: Watchdog Legions

And another example, this time from Cyberpunk:

Source: Cyberpunk 2077

Normally the leg geometry is exchanged for a different one. Theoretically, blend shapes could also be used, but these are expensive.

⚠️ Important: Only the mesh changes, not the skeleton. This means that the ankle around which the foot rotates still has the same position:

This can lead to strong visual distortions like in Final Fantasy 14:

Source: Reddit Discussion

In contrast, the ankle should be at this point when wearing high heels. Of course, you can never switch to flat shoes in Nier, so they could fit the skeleton perfectly:

Source: Platinum Games Blog

🦵 3. Bend

Here’s a nice example where sychnorized character heights are very important (otherwise the lips wouldn’t meet when kissing), but instead of shortening the lower leg, the legs are simply bent a bit more:

Source: 3D Sex Villa 2

Posture

If you want to do it right, it’s not enough to just lift the hips and turn the feet into the “high heel” pose. According to this and this article, the whole posture changes! The main differences:

  • redistribution of body weight
  • forward tilted pelvis, spine arches gently
  • engaged calf muscles
  • accentuated curve of the buttocks
Source: Why Shoes Make
“Normal” Gait Impossible

I tried to adapt this to my zombie by doing the following (I refrained from doing a blended shape for a fuller bum though):

  • Raise the hips
  • Rotate the feet (so that they meet the floor again)
  • Redistribute the body weight by tilting the pelvis and arch the spine
Source: Mixamo “Romero”

And I did a test with a walking animation. I added my posture change as an additive to a mixamo walking animation and it worked! Check out my sexy zombie :)

Source: Mixamo “IV Pole Walking

By the way #1, I noticed a little detail in Cyberpunk: when the shoe is swapped, we can briefly see how the foot pose changes:

Source: Cyberpunk 2077

By the way #2: If you want to be really precise, you should also change the orientation of your big toe, as it is often squeezed unnaturally into the shoe:

Source: Foot in High Heel Turntable

Animation

Apart from height and posture, you may also need to change the entire animation, as high heels can drastically alter the gait:

“High heels encourage shorter, more deliberate strides, leading to a smoother and more controlled walking motion”

This article even provides a little graphic showing the changes. They did a lot of motion capture analysis with 12 women:

Source: Human Gait Analysis using 3D Motion Capture

And here we are at another cross road for game developers!

If you’ve decided to reuse only the flat shoe animations, don’t sweat it! I’ll give you two reasons not to worry too much:

  1. Other developers do the same
  2. Even in high heels a “normal” walk is possible

😊 1. Other developers do the same

Most games simply reuse their animations. The only example I could find where custom animations are used is a Skyrim MOD! There, the animation of the high heels leads to a crossing of the legs and a more accentuated hip movement:

Source: Conditional High Heel Walk

And yes, it is true that such a gait can be observed in real life:

Source: Who says men not walk in heels

But…

👠 2. “Normal” Walk in High Heels

Such a cross-over gait is also possible with FLAT shoes (left), while a moderate cross-over (center) or no cross-over at all (right) is also possible with high heels:

Source: Shutterstock

So wearing high heels doesn’t mean that your legs automatically cross and your hips go crazy. But if that’s what you want and your game “only” offers flat shoes, you can still do it. Anything is possible!

By the way, not even Nikki has a unique animation per shoe and this game is all about outfits and dressing in style:

Source: Infinity Nikki

What they do have, however, are different idle animations. I counted four different ones, depending on which shoe you’re wearing. That’s quite a lot in my eyes:

Source: Infinity Nikki

Optimization

What happens to the polygons of the leg when it is covered by a shoe? Good handling can help prevent clipping, and of course it’s a nice optimization.

This is what we want to prevent:

Source: Daz To Unreal – Dealing with Heels

Some games hide the polygons inside shoes. In Saints Row, the legs are made up of different pieces and can be hidden if necessary:

Source: Saints Row

Watchdogs is also an interesting example:

  • Left: The whole leg is a single draw call and it is complete (the toes are there, even though they are covered by the shoe)
  • Right: same location, only with a flat shoe. Now the leg is made up of multiple meshes (aka draw calls). I’m not sure why, as both shoes show about the same amount of skin…. strange! But in this case, the toes are optimized away!
Source: Watchdog Legions

Here is a static comparison of how the game handles the reduction of polygons:

  • High Heels: Full leg (with toes) is used.
  • Flats: Leg made of several pieces; Toes are removed.
  • Boots: Leg made of several pieces; Lower leg removed.
Source: Watchdog Legions

And cyberpunk? They just keep the whole leg, even if the boots are massive and cover most of it!

Source: Cyberpunk 2077

Audio

Depending on whether the shoe has a stiletto heel, the steps should sound different. The same applies if you are not wearing any shoes at all (barefoot). Cyberpunk does a good job here:

Source: Cyberpunk 2077

If you’re playing a competitive game, high heels might give away the player’s position more easily as they’re usually louder. This could be a balancing issue!

Bonus Work

You’ve already built high heels into your game, everything works perfectly and now you’re bored? Here are some challenges:

Source: Ultimate Heel Guards for Walking on Grass
  • Implement a higher range and damage for fighters wearing high heels but also add a 5% chance that they slip and need a long pause to recover:
Source: #1 #2

Summary

  • Supporting different shoe types may change the characters height and foot orientation (and maybe hit volumes).
  • If precise interaction with the environment or NPCs is necessary, the consequences for the height change require solutions (unique animations, IK systems) or workarounds (shorten lower legs, bent legs)
  • Different shoe types may also change the posture, gait and footstep sound (the latter could pose a balance problem in competitive games).
  • Many games use the same animation for all shoe types (but special cases such as motorcycling or sneaking with high heels may require special attention).
  • Sometimes the polygons that are covered by the shoe are removed for optimization (can also prevent clipping). Usually meshes are swapped as blend shapes are too expensive.
  • A graceful gait (crossed legs, accentuated hips) is also possible with flat shoes, while a “normal” gait is also possible with high heels.

History Lesson

Originally, men started wearing high heels and then women adopted – “it was in an effort to masculinise their outfits”.

Sources

Articles & Studies

References

Tutorials & Discussions

General

Blender

Maya

Unity

Unreal

Unreal Content Example Map: IK Rig

Wearing Examples

Effect on Health

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