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.
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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.
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If you do not know how the Shader Editor Works see Blender Nodes.
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