Mesh Tension Addon

The Mesh Tension Addon generates vertex groups and vertex colors where there is compression of stretching on a surface. This all happens during animation, real-time. You can use the vertex colors (vertex paint) for shaders. And you use the vertex groups (weight paint) for everything else.

While you don’t see the weight paint updating in real time in weight paint mode, it’s effect does. For example when you add a particle system and you assign vertext groups to Desensity and length. The same for vertext paint: in Vertext Paint you don’t see animated paint but when you use it in a shader (attribute node) you see the effect. To get the desired strength, you go to the properties panel, and Object Data Properties. There you find the settings for Tension Maps like Strength and Bias. Especially the Bias affects vertex colors.

How the add-on works

• First, enable Lock Interface. You can find this in under Render in the 3D viewport’s menu.
• Then animate an object with an armature. (I couldn’t get it to work with shapekeys, but it seems that should work too).
• Once animated you select the object and go to the properties panel. Under the Object Data Properties you enable Tension Maps.
• And that is pretty much it. Now you need to find an application for it.

Once done, you see in the Properties Panel, Object Data Properties two new Vertex Groups and one Vertex Colors. Below a screenshot of that.

So now we gathered some data and feed it into something. Here I feed it in to a shader with help from the Attribute Node. So, in the Attribute node you type: tension_map, like below.

And the white material where there is compression you see a particle system with metaballs in this case. You can use the Vertext Groups in the Properties Panel> Particle Properties> Vertext Groups. Just like as shown below.

Where to download the Mesh Tension Addon?

Check this post on Blenderartists.org and you just install the addon as usuall in Blender. It’s a single .py file.