bv-1000-Concentric-Circles – Default Cube
This video provides some great information on creating concentric circles on a plane with nodes created in the Shader Editor.
This basic node schematic will create a starting place for creating and endless variety of forms.
Watch the complete video for details on how it works (I added the color ramp).
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This pattern on a sphere can be made from the schemaic below.
The image is in two parts to make it easier to read.
If you do not know how the Shader Editor Works see Blender Nodes.
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