What are my options for in-game customizable models with no art experience?

[rectifier0001]

I'm a programmer and I get ideas about making porn games sometimes. The kind of game I'd want to make would be something very free-form using a full fledged game engine (e.g. Unity, Godot). Specifically, I'd love to have a system in game for genetics and/or character customization. This would require dynamic alterations to character models - think VaM or Breeders of the Nephelym. How do games like that accomplish this? Do they just have one or two base models which get altered through mesh-warping animations? Would I be able to find free models for that, or would I have to try to make them myself? Any help is appreciated; I know I can do all the coding I need, but the art side is foreign to me.

 

[JoGio]

You can think of character customization as happening through three distinct avenues:
1) Texture/Material Change: This is when the model remains exactly the same, but the texture/material applied to it is changed. The most obvious use would be changing skin color or hair color (color in general). In the anime art style, many games use textures for faces/expressions, for example. In high fidelity games, the texture can be something like the complexion/wrinkles/details on a face.

2) Partitioned Models: In this case, the body of the character is split into different parts. Different variants are made of each part and are swapped to create different looking characters. The most basic use of this can be seen in many older RPGs like Skyrim where all male characters have one shared body, but the head and neck are a separate mesh, allowing the game to swap between different head models for different races (elves, orks, humans, etc.).

The skeleton driving the character's animations can be one skeleton, but the meshes deformed by it can be partitioned as much as you like. However, the tricky part about partitions is that, if done incorrectly, gaps can appear where the edges of the different parts meet.

3) Shape-keys/mesh deformation: This is what Daz calls "morphs". It's where the mesh is exactly the same but the vertices are arranged differently, creating a different look. You see this in games that use a slider to modify parts of a character. You can use shape keys to make a body mesh look lithe or muscular through a single slider a la Skyrim. You can also use it to change the shape of eyes, make lips look fuller or thinner, make cheeks look plump or gaunt, etc. You can also use shape keys to give a female character a pregnant belly and enlarge her breasts as well.

Shape keys can also be used to animate characters. Most often, they're used to animate faces or objects that are somewhat amorphous, like a slime or goo.


In terms of ease of use, I would say Textures/materials are easiest to use, then shape keys, then partitioned models. That being said, making 3D characters customizable is an incredible undertaking. It's a lot of work and you need good knowledge of modeling, texturing, materials, and rigging to make it work convincingly.

 

[rectifier0001]

You can think of character customization as happening through three distinct avenues:
1) Texture/Material Change: This is when the model remains exactly the same, but the texture/material applied to it is changed. The most obvious use would be changing skin color or hair color (color in general). In the anime art style, many games use textures for faces/expressions, for example. In high fidelity games, the texture can be something like the complexion/wrinkles/details on a face.

2) Partitioned Models: In this case, the body of the character is split into different parts. Different variants are made of each part and are swapped to create different looking characters. The most basic use of this can be seen in many older RPGs like Skyrim where all male characters have one shared body, but the head and neck are a separate mesh, allowing the game to swap between different head models for different races (elves, orks, humans, etc.).

The skeleton driving the character's animations can be one skeleton, but the meshes deformed by it can be partitioned as much as you like. However, the tricky part about partitions is that, if done incorrectly, gaps can appear where the edges of the different parts meet.

3) Shape-keys/mesh deformation: This is what Daz calls "morphs". It's where the mesh is exactly the same but the vertices are arranged differently, creating a different look. You see this in games that use a slider to modify parts of a character. You can use shape keys to make a body mesh look lithe or muscular through a single slider a la Skyrim. You can also use it to change the shape of eyes, make lips look fuller or thinner, make cheeks look plump or gaunt, etc. You can also use shape keys to give a female character a pregnant belly and enlarge her breasts as well.

Shape keys can also be used to animate characters. Most often, they're used to animate faces or objects that are somewhat amorphous, like a slime or goo.


In terms of ease of use, I would say Textures/materials are easiest to use, then shape keys, then partitioned models. That being said, making 3D characters customizable is an incredible undertaking. It's a lot of work and you need good knowledge of modeling, texturing, materials, and rigging to make it work convincingly.

Thanks, that's interesting to read. I was definitely thinking about shape-keys, though I hadn't heard that name. I'm pretty sure I can figure out the rigging, and I understand models, textures, and materials from a technical standpoint. My main blocker is that I don't know how to acquire a suitable base model for shape-key deformation to begin with.

 

[JoGio]

My main blocker is that I don't know how to acquire a suitable base model for shape-key deformation to begin with.

I've seen games use Daz models in unity or Unreal. You will need to pay for the real-time license to use them without licensing issues.

There is also

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.

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can be used to generate character models for free but I never liked the results.

Epic has their

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if you plan to use Unreal.

Part of the difficulty with creating adult games is finding models with usable and variable genitalia. To cut cost, you could try finding a character tool that gives you all the different body types, hair, and faces you want, minus the lewd bits, then commission an artist to create those for you.

You can also commission artists to create the shape-keys you want once you find suitable base male and female models.

You might want to have jiggle physics for breasts and butts. Some character rigs (the skeleton used for animating) may not have bones that you can apply physics to. In that case you may need to make your own rig. If you need to go that route then you might be interested in Blender's rigify tool to help you get a good rig with relatively little effort.

The penis and testicles can be a seperate model with it's own little rig which you can then attach to the body rig's pelvis bone (this would ideally be done in-engine). You will likely have a small seam where the body and genitelia meet unless the gens are made to fit the body perfectly.