GPR_$SPLINE_CUBIC_Y GPR Calls GPR_$SPLINE_CUBIC_Y
NAME
gpr_$spline_cubic_y - draws a cubic spline as a function of y.
FORMAT
gpr_$spline_cubic_y (x, y, npositions, status)
DESCRIPTION
This routine draws a cubic spline as a function of y through the control
points.
gpr_$spline_cubic_y draws a smooth curve starting from the current posi-
tion and through each of the specified points. The y coordinate of the
current position has to be less than the first y coordinate in the y
array.
The specified coordinates are added to the corresponding elements of the
coordinate origin for the current bitmap. The resultant coordinate posi-
tions are the points through which the spline is drawn.
After the spline is drawn, the last point becomes the current position.
Input Parameters
x List of the x-coordinates of all the successive positions.
gpr_$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 y-coordinate is less than or equal to a pre-
vious y-coordinate. The y-coordinate array must be sorted into increas-
ing order.
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.