How to pass parameters to vertex shader at runtime

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The ShaderParam plugin can be used to define shader parameters in the sdf file. However, except for the 'time' variable, these are all constant values.

What is the preferred way to set such variables during runtime?

E.g. for the deformable sphere example: let's say we want to change color of the sphere at runtime, based on user input. How could this be done?

Is there a way to do this on a per-model basis? E.g. if you'd spawn multiple of those spheres, change the color of a specific one.