IDEA / Procedural Character Generator

I did something like this in the past by drawing by hand. But now we can do it procedurally, how? Shape Keys and Skin Modifier!

Continue from my previous post about "modeling anime character in 3D in Blender using Skin Modifier",  I am now thinking of something that is a little bit ambitious, but maybe worth trying and perhaps you are also interested to explore this area.

Stick Figure Doodles in 2D. How about 3D?

This is one idea I have been wanting to do: to create some kind of CHARACTER GENERATOR based on properties such as:

• Gender: Male, Female
• Age: Baby, Child, Teenager, Adult, Old
• Body Shape: Fat, Skinny
• Leg and Arm: Short, Long
• Body Height: Tall, Short
• Head shapes: triangle, round, upside down triangle, square
• etc

There are 2 ways we can approach this using Skin Modifier:

1. Mix and Match method
2. Morph method

It is kind of like "crowd" procedural system.

Before going too far, I will try with a simple test first with "generic character" in mind.

SHAPE KEYS & SKIN MODIFIER
We know that Skin Modifier only requires Poly Mesh Edges to generate mesh. Being Poly Edges, it is quite easy to create Shape Keys that "morph" between different "edge shapes" which then updated down the line.

I will just use generic Stick Figure kind of character:

Even with stick figure, think the bare minimum of "Joints" anchor or pivot this character would have:

• Head
• Neck
• 3 for torso (chest, spine, pelvis)
• 3 for arm: shoulder, elbow, wrist 
• 3 for leg: hip, knee, ankle

I am not changing the point "weight" of this character yet. From my previous test, point weight of Skin Modifier is not morphed by Shape Key.

Shape Key maintains the same point weight array that you give during Edit Mode (by selecting point and hotkey Ctrl+A).

The point weight is an important feature that will give a lot of character to your 3D figure, so keep this in mind.

NEXT STEP: SHAPE KEYS

Create some Shape Keys, based on that simple edges. Make the shapes so that they are all can be added on top of each other.

Grow the character from the leg up to torso, branching into arms, neck, head as required. Imagine a tree growing from trunk into branches into smaller branches.

For examples:

Long Arm: (extend arm)

Long Leg: (extend leg)

Since our character is super simple, we only need to worry about: Head/Neck, Torso, Arm, Leg. Once you got the Shape Keys, you can start generating some character morph.

Change the Range Min and Max so that you can easily have the reverse effect: Short Arm, Short Leg, Short, Head, Short Torso. Do some variations.

RESULTING CHARACTER MORPHS

Like I mentioned above, the "weight" of each point matters. So when you start to give some volume characteristic, things started to get interesting.

The Skin Modifier will only keep a set of weight array you specified for that particular setup. So if you make the head point weight as BIG, then it will be BIG all the time. Unless I am wrong and you can animate the weight, I need to double check with Nicholas Bishop.

Anyhow, you can always have few different model variations of WEIGHT.

Each one of this stick figure character is still manipulable via Shape Keys.

We can actually add more detailed feature such as Hands, Feet, Fingers, Antennas, Wings, even when we are already gone quite far in this process.

Try applying all kind of modification (in Edit Mode) to the Basis Model or the Shape Keys and check the result instantly.

With this method, we can end up with unlimited 3D alien creature design just by mixing few properties. Remember we only started with just a stick figure!

FURTHER EXPLORATIONS

Probably we could explore this a little bit more in the future for character with a more refined chracter shapes. We are not limited to a character with two legs and to arms. You can have all kind of creatures with different properties and mix and match the design.

Even better, with some Python scripting that "randomize" the shape keys, you can have unlimited array of varieties from a single base model.

Trust me, I attempted to do this using other package (Maya, Houdini, etc), this is by far the most practical and robust without having to script.

UPDATE: QUICK TEST
Using the female "anime" character I built previously, I tried to extend it so I could have a little bit variations (in proportion):

Baby/Toddler

Girl/Teenage

Young Adult

Low poly version.

Parameter to control the length of limbs.

I leave the Head part just like that for now without any Shape Keys modification, but I think the head needs its own separate Skin Modifier setup for better control over the resulting mesh.

If your animation requires a simple character like this Intel "Me The Musical" below, you can just use Skin Modifier.

See Also:
EXOCORTEX SPECIES
http://www.exocortex.com/Plugins/Species

UPDATE 2013.01.11:

Thanks for the link share from the comment:
TERAWELL: Japan tool for character generation and pose
http://terawell.net/