Smooth Adulthood (a failed experiment)

[tomcat]

Maybe someone will be interested…

An attempt was made to create a smooth character maturation and aging in the game. The game was supposed to be a life simulation game. Externally similar to the The Sims (The Sims 3). The game is developed on the Godot engine.

This is what I was able to accomplish. Here is the result of the animation assignment at 10 stages of aging (from 1 year to 25):

0001-0110_6w.mkv File size: 1.46MB

Animation (02_01 walk) taken from cgspeed and a little bit finalized.
02_01.bvh File size: 254KB

The transition between stages is completely unacceptable:


There are a total of 90 frames of growing up from 1 to 25 years old according to MH. Growing up is divided into 10 steps (stages).Each stage consists of: a central mesha with a rig to which the body is attached and two morphs - the initial (young) and the final (old).

For example:
Stage: 4
Frames: 25(morph)/30(mesh, rig)/35(morph)
Years: 3/4/5
Height: 0.785945 m/0.849867 m/0.927994 m

Stage: 5
Frames: 35(morph)/40(mesh, rig)/45(morph)
Years: 5/6/7
Height: 0.927994 m/1.00612 m/1.09845 m

Table with details in pdf.

stage_2.pdf

(50.89 KiB) Downloaded 201 times

The morphs of the end of one stage and the beginning of the next coincide.

morphs Stage 4/frame 35 = Stage 5/frame 35. But their rigs are different.

The thought is that the distortions will be negligible. And for the static pose it was exactly that:


godot_exp_25_01.avi File size: 15.91MB

Growing up (changing stages) happens in an idle mode (rest or sleep) and is not sionally noticeable.

And it fell apart with the animation…

You can take a look at the Blender 2.93 file.
shape_transform_anim_separation_final_public.blend File size: 31.78MB

In theory, you can make stages for every step of growing up. But there are about 100 of them. And for each stage, then need to prescribe a variation of rig for different height and width of the shoulders/hips, arm and leg length (all where the skeleton changes) + about 1.4k target files for morphs. Unreal amount of work.

While I have no other ideas…

[punkduck]

oops. I answered with a PM. It happens because the shape keyed growth animation is bound to a skeleton which is not growing the same time. The armpit is above the skeleton and then the weight equation is flipped. (It is simply a distance algorithm afaik).

I tried to make a proposal by resizing the skeleton and not using morphs, because only 5-6 frames are used with one character (which results in 0.25 seconds). In this case the arms are not flipped.

The animation would be changed into 10 different characters and using the resize of the hip bone (parent bone for all others) to create the frames in between.

[tomcat]

First of all, thank you very much for trying to resolve the issue.

I tried to make a proposal by resizing the skeleton

Scaling the skeleton along with the body is probably the solution. But I suppose it would create other problems in the animation. For example, the combination of interaction with objects will be broken: to sit somewhere a character, lie down or pick up an object, for this it is necessary all the time to monitor the current scale of the rig and correct the position and animation. And also need to take into account that in addition to age, there should be other modifiable parameters rig (height, length of arms/legs). And interacting with other characters with changing rig (such as hugs) turns into an impossible quest.

[AKNightHawk]

I am not sure what could be done with Blender because I do not use it. But I think the mesh could use the blend shapes from make human directly. To change the mesh from a kid to an adult. In 3Ds max you would just change the shape of the character in an FBX file. Start them as a baby first. Then change the stage to the next age in Make Human. Export the fbx file. Load up the baby in max. And use the Morpher to change the baby. By loading the 2nd stage fbx file into max. Then do the same for the 3rd stage and so on. I am not sure how blender does it. (If you have to use more than one model to make blendshapes.) I will experiment in max for ya and see if I can get it working. With that system, I should still be able to use the same skeleton on the mesh and let it grow with the child. But I am not sure.

Also I will give a better explanation tomorrow when I wake up hehe. I will test it out first and send you a video.

[tomcat]

Thank you so much for the comprehensive answer!

Load up the baby in max. And use the Morpher to change the baby. By loading the 2nd stage fbx file into max. Then do the same for the 3rd stage and so on. I am not sure how blender does it. (If you have to use more than one model to make blendshapes.)

If I understood the sentence correctly, Blender has Shape Keys. There isn't much of a problem doing a body grow in a static pose. The unbridled fun begins when trying to set an animation — any movement. The point is that each step of body maturation must correspond to a suitable rig. Otherwise the animation will not look elegant, and for this the skeleton must change according to the shape of the body. And this is what I failed to do.

Making children in the game is not very difficult. It's hard to make them grow up.


Translated with http://www.DeepL.com/Translator (free version)

[tomcat]

Well, you can't say it's elegantly solved... but it'll probably do for a prototype.



shape_transform_size.mp4 750 KB

Made this way: when growing up, the body is scaled, only the proportions of the head (and a bit of the neck) are changed, and the young facial features (the shape) are applied. The body doesn't change, except for the prominent parts in women.

A child's adult body is not good, of course,but I don't see any other way yet.

[tomcat]

I'm still on that subject…

There's an addon for Blender. Maybe it can help solve the problem:

Game Rig Tools (Blender Addon)