Why use SphereGeometry over IcosahedronGeometry?

Seems like IcosahedronGeometry makes a better sphere than SphereGeometry.

Whe would we actually want to use SphereGeometry over IcosahedronGeometry to make a sphere?

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SphereGeometry has a UV mapping that is equirectangular, which is useful for a lot of cases. It also has a quadrilateral topology rather than triangles, and the default sphere in blender is the same.
So you can slap an earth texture on it and get a planet, which iirc isn’t the case with IcoSpheres. The generation for the uvsphere is also conceptually simpler, as its just a grid warped to a sphere.

Icosahedron geometry generation is a bit more complex… in that it is a subdivided tetrahedron with normalized vertices. So it has 4 poles, and the triangles are all equal area.
Icospheres are nicer for custom shader stuff where you’re warping the geometry. So they each definitely have their own place in the toolbox.

Another alternative somewhere in between Ico and UV is the subdivided BoxGeometry where you normalize the vertices. This kind of sphere has 8 poles (one at each cube corner) rather that the 2 poles of a UV sphere, so it has more uniform area across faces.

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In addition to what @manthrax elaborated, it is much easier to cut a 3D pie from a SphereGeometry.

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Different approaches are often needed for different requirements.

See Collection of sphere definitions

For example, a sphere made of eight individual parts is very suitable for creating a cuboid with exactly symmetrical rounded corners.

Magic Sphere => Magic Box

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Man that list is epic! :smiley: A+

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