stars and curvature
Most Islamic domes aren’t spheres posing a supplementary challenge. The designers absorbed the changes of curvature by using different types of stars. In the article Girih for Domes: Analysis of Three Iranian Domes the authors Mohammad Hossein Kasraei, Yahya Nourian and Mohamadjavad Mahdavinejad compare the pattern of some Iranian domes. They conclude that the number of points of the stars depend on the
curvature of the dome. Zones with a greater curvature match with stars with a greater number of points and opposite. A different progression of curvature leads to a different progression of stars. E.g. in the Yazd domes the curvature and the number of star points decrease starting from the base of the dome while the progress in Saveh is totally different. Here the progression of the curvature isn’t equal but in two phases. So is the number of points of the stars.
