Optimization of JCMs and Flections

[garden]

I have done some research on the effect of mute shapekeys on optimization.
G8+FACS - 83fps
G8+FACS (mute all) - 83fps

G8+JCMs - 73fps
G8+JCMs (mute all) - 95 fps
G8+JCMs + Mute Drivers - 90fps

G8+Flections - 92fps
G8+Flections (mute all) - 96fps

G8+Flections + JCMs - 67fps
G8+Flections + JCMs (mute all) - 91fps

As we can see, mute shapekeys FACS do not affect performance, but mute shapekeys JCMs and Flections do, and significantly.
Perhaps FACS shapekeys affect a small number of polygons, and JCMs affect a large number of polygons, so there is an influence of mute.

So, I suggest adding for JCMs shapkeys and Flections shapkeys drivers for mute, which will be mute shapkeys if the value of the JCMs and Flections morph driver is 0.
I have already done this manually with the model I imported JCMs into and it works fine.

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Video
Here is a video, the program for video recording spends about 10-15 fps, but even with it you can see that the fps is more than 73 that were without mute.

The driver expression should be "1-a", or "1 if a<0.0001 else 0", because a==0 does not work correctly, it looks like some drivers are equal to 0.00000...01 even in a calm state.

[Thomas Larsson]

Implemented in last commit. Zero morphs are muted for jcms and flexions, both with easy import and if they are loaded manually. I also added muting as an option for custom morphs. The expression is set to abs(a) < 0.0001, to make it work also for negative morph values. Clothes shapekeys are muted when the corresponding body shapekeys are.

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