A surface is like a rectangular stretchy rubber sheet. The NURBS form can represent simple shapes, such as planes and cylinders, as well as free-form, sculptured surfaces.
All surface creation commands in Rhino result in the same object: a NURBS surface. Rhino has many tools for constructing surfaces directly or from existing curves.
All NURBS surfaces have an inherently rectangular organization.
甚至于圆柱面这样的造型也可以看作是一个矩形面首尾相接构成的，相接的边缘处被称为接缝，即使一个造型看起来不是矩形结构，它也是通过矩形结构修剪或移动了边缘的控制点形成的。
曲面可以是开放或封闭的，两端开放的圆柱面，有一个方向是封闭的。
环状体在两个方向都是封闭的。
Draw a rectangular planar surface.
Draw a rectangular planar surface with a bitmap texture.
Fit a rectangular planar surface through points.
Draw a surface from a grid of points that represent surface control points.
Draw a surface from three or four corner points.
Draw a surface from a grid of points that lie on the surface.
Drive closed planar curves in a straight line.
Create a surface from two, three, or four curves.
Extrude a curve on a surface in the surface normal direction.
Fit a surface through profile curves that define the surface shape.
Fit a surface through a network of crossing curves.
Fit a surface through curves and point objects.
Create a planar surface from planar curves.
Revolve a profile curve around an axis and along a rail curve.
Create a surface by revolving a profile curve around an axis.
Offset a curve and create a ruled surface between the curves.
Fit a surface through profile curves and one edge curve.
Fit a surface through profile curves and two edge curves.
Create planar surfaces through objects at specified locations.
将矩形的点物件阵列往使用中工作视窗工作平面的方向投影至物件上，并建立通过投影点的曲面。
Copy a surface parallel to the original.
Copy a surface specified varying distances from the original surface.
Flatten (develop) a surface or polysurface with curvature in one direction to a planar surface.
Create a surface based on gray-scale color values in an image file.
Duplicate each mesh face with a NURBS surface.
将曲线或曲面镜像，并使两个曲面以设定的连续性相接。
请参考
