This paper gives the methods generating cubic B-type spline curves with a shape parameter #alpha# and surfaces with two parameters #alpha# and #beta#.Under the condition of fixing the contorl points,these curves/surfces C~1 continuity and have many principal properties of common cubic B-spline curves/surfaces.The position and the shape of the curves/surfaces cna be mdoified by changing the value of #alpha# or #beta#.When #alpha# and #beta# tend to zero,they glovally approximate to contrl polygon/control net.As an important application,we also present a method smoothly approximating general compound straight-grained surface.
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