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+cstypes
+
+bezier
+
+Type bezier specifies a sequence of Bezier curves of similar degree, each
+beginning where the prior terminated.  If there are multiple curves in the
+sequence, then the initial control point of a latter curve is not explicitly
+specified since it is equal to the last control point of the prior curve.
+
+Consider the following example.
+
+    curv2 -6 -5 -4 -3 -2 -1 -6
+
+When the degree is 3, the above specifies two Bézier curves: C₁=(-6,-5,-4,-3) and
+C₂=(-3,-2,-1,-6).
+
+The Bézier curve functions are taken to be branches of a peicewise function C
+obtianed by dividing the parameter space into regions and mapping each region
+to a different curve.  For example,
+
+    parm u 0.00 1.00 2.00
+
+specifies two intervals, [0,1] and [1,2].  If the parameter is between 0 and 1,
+it will be mapped via the first curve C₁ and if it is between 1 and 2, it will
+be mapped via the second curve C₂.  In order to maintain continuity, an affine
+transformation will be applied first to obtain a value between 0 and 1 so that
+C(1.5) = C₂(0.5).
+