Think of a sphere that can 'reach out and touch' others of it's own kind... with a given strength and size, a metaball deforms to meld with others. The closer they are the stronger the connection between the two. The blobs can run together and merge if they are close enough, or a negative metaball can indent another. The area of the metaball that reaches out is rendered fluidly/smoothly. Thus you can create more organic/natural items, such as raindrops, muscles, etc. Note: they only do this magic trick between metaballs... if you throw a regular sphere into the mix, it just sits there.. grin

RosemaryR
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"This...this is magnificent!"
"Oh, yeah. Ooooo. Aaaaah. That's how it starts.
Then, later, there's ...running. And....screaming."