Icosphere drawing

[dkurtaev]

Better if planet's model is icosphere instead UV sphere. UV sphere has north and south pole where a lot of triangles compressed in single point. At icosphere all vertices owned only by three triangles.

Study how draw it.

[dkurtaev]

Icosphere based on an icosahedron. Icosahedron may be defined by length similar for each edge. Totally has 20 triangles, 12 vertices.

On picture computation of support planes width and height:

[dkurtaev]

Vertices of icosahedron located on the future icosphere. Procedure of icosphere building in next steps:

• Split each edge in halves.
• Instead each triangle make four triangles inside it. Example.
• Normalize each new vertex for locating it on icosphere.

Described procedure may repeated for smoothing icosphere.

Figure	Number of vertices	Number of triangles	Image
Icosahedron	12	20	Link
Icosphere x1	42	80	Link
Icosphere x2	162	320	Link
Icosphere x3	642	1280	Link