cairo-curve-to (cr x1 y1 x2 y2 x3 y3)

cr -- a cairo-t context
x1 -- a double float x coordinate of the first control point
y1 -- a double float y coordinate of the first control point
x2 -- a double float x coordinate of the second control point
y2 -- a double float y coordinate of the second control point
x3 -- a double float x coordinate of the third control point
y3 -- a double float x coordinate of the third control point

Adds a cubic Bezier spline to the path from the current point to position (x3, y3) in user-space coordinates, using (x1, y1) and (x2, y2) as the control points. After this call the current point will be (x3, y3).

If there is no current point before the call to the cairo-curve-to function this function will behave as if preceded by a call to:

(cairo-move-to cr x1 y1)