Why vertex painting has sharp edges of the puddle?

I use vertex painting to create a puddle. Tell me please how to make the smooth edges? They were smooth, and then became straight lines.

http://f6.s.qip.ru/sGa1lvNr.png

and that is necessary for me

http://f5.s.qip.ru/sGa1lvNs.png

Try making your mesh more tesselated (More Vertices) so there are more points to paint on which will make much smoother looking puddle edges.

Maybe you also need to add more noise/variation to you vertex color.
Take a look at this page: you’ll find something useful :slight_smile:
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