UV Mapping is the process of mapping a 2D texture to use onto a 3D object.
When UV Mapping and Texture Painting, there is sometimes a “bleeding” issue. This happens because some points of the UV map end up very close to other parts mapped to topologically-distant elements.
To prevent that issue, increase the Island Margin Value while creating the UV map, which will just create a space between those elements in the UV Map.
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