Why not just use conics' equations to draw them but Bspine I'm wondering.
jacheng
I looked up why circles can't be represented using a bezier. Turns out it is because you need a squareroot function to encode a circle, which the bezier equations does not have.
@Heisenberg The real point is simply that rational B-splines can represent a strictly larger set of shapes than ordinary B-splines. There are also plenty of scenarios where you need to mix conic sections with more general freeform shapes (e.g., a cylindrical surface in an engine block).
Why not just use conics' equations to draw them but Bspine I'm wondering.
I looked up why circles can't be represented using a bezier. Turns out it is because you need a squareroot function to encode a circle, which the bezier equations does not have.
https://stackoverflow.com/questions/1734745/how-to-create-circle-with-bézier-curves
@Heisenberg The real point is simply that rational B-splines can represent a strictly larger set of shapes than ordinary B-splines. There are also plenty of scenarios where you need to mix conic sections with more general freeform shapes (e.g., a cylindrical surface in an engine block).