Hi dears

I want to know about bezier surfaces,i heard the the name of Bezier surfaces but don’t have any information about this.

Thanks a lot dear menno for your attention

I have read if we have 4 single span curves (e.g: degree=3 & point count=4) and make a surface with them by EdgeSrf this means our single span surface is a **Bezier surface**.

I want to know is it true ?if true what is difference between Nurbs and Bezier surface or curve?

Bézier surfaces part of the larger family of NURBS surfaces. If the degree is one less than the point count a NURBS surface is a Bezier surface.

Another way of saying this: a Bezier surface is always a NURBS surface, and a NURBS surface is a Bezier surface iff the degrees in each direction is equal to the point-count minus one in each direction.

… and all point weights are = 1.

Philip

I don’t think so, a rational Bezier surface is a thing AFAIK.

Take a circle, extrude it, then run *ConvertToBeziers* - you will get four rational Bezier surface patches of degree 2 in the arc direction and degree 1 in the extrusion direction.

The original version of Bezier curves and surfaces were non-rational (no division). This equivalent to being rational with all weights = 1.

McNeel may be using an expanded definition of Bezier curves and surfaces with rational versions.

Thanks a lot dear menno

Thanks a lot dear Philip

Thanks a lot davidcockey

Your mean is: we don’t have rational Bezier curve or surface and this is a bug in rhino?