Relative-coordinate version of cairo_curve_to(). All offsets are
relative to the current point. Adds a cubic Bézier spline to the
path from the current point to a point offset from the current
point by (dx3, dy3), using points offset by (dx1, dy1) and
(dx2, dy2) as the control points. After this call the current
point will be offset by (dx3, dy3).
Given a current point of (x, y), cairo_rel_curve_to(cr, dx1,
dy1, dx2, dy2, dx3, dy3) is logically equivalent to
cairo_curve_to(cr, x+dx1, y+dy1, x+dx2, y+dy2, x+dx3, y+dy3).
It is an error to call this function with no current point. Doing
so will cause cr to shutdown with a status of
CAIRO_STATUS_NO_CURRENT_POINT.
Since 1.0
Relative-coordinate version of cairo_curve_to(). All offsets are relative to the current point. Adds a cubic Bézier spline to the path from the current point to a point offset from the current point by (dx3, dy3), using points offset by (dx1, dy1) and (dx2, dy2) as the control points. After this call the current point will be offset by (dx3, dy3). Given a current point of (x, y), cairo_rel_curve_to(cr, dx1, dy1, dx2, dy2, dx3, dy3) is logically equivalent to cairo_curve_to(cr, x+dx1, y+dy1, x+dx2, y+dy2, x+dx3, y+dy3). It is an error to call this function with no current point. Doing so will cause cr to shutdown with a status of CAIRO_STATUS_NO_CURRENT_POINT. Since 1.0