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GPR_$SPLINE_CUBIC_P               GPR Calls                GPR_$SPLINE_CUBIC_P


NAME
     gpr_$spline_cubic_p - draws a parametric cubic spline.

FORMAT
     gpr_$spline_cubic_p (x, y, npositions, status)

DESCRIPTION
     This routine draws a parametric cubic spline through the control points.

     gpr_$spline_cubic_p draws a smooth curve starting from the current posi-
     tion, through each of the specified points.  The current position cannot
     be equal to any point specified by the call.

     The specified coordinates are added to the corresponding elements of the
     coordinate origin for the current bitmap.  The resultant coordinate posi-
     tions are the points through which the spline is drawn.

     After the spline is drawn, the last point becomes the current position.

   Input Parameters
     x    List of the x-coordinates of all the successive positions.
          gpr_$coordinate_array_t, a ten-element array of 2-byte integers, is
          an example of such an array.  The actual array can have up to 32767
          elements.  The values must be within the bitmap limits, unless clip-
          ping is enabled.

     y    List of the y-coordinates of all the successive positions.
          gpr_$coordinate_array_t, a ten-element array of 2-byte integers, is
          an example of such an array.  The actual array can have up to 32767
          elements.  The values must be within the bitmap limits, unless clip-
          ping is enabled.

     npositions
          Number of coordinate positions.  This is a 2-byte integer in the
          range 1 - 32767.

   Output Parameters
     status
          Completion status, in status_$t format.

NOTES
     An error is returned if any two consecutive points are equal.

     When you have clipping enabled, you can specify coordinates outside the
     bitmap limits.  With clipping disabled, specifying coordinates outside
     the bitmap limits results in an error.

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