conicTo abstract method
Adds a bezier segment that curves from the current point to the given point (x2,y2), using the control points (x1,y1) and the weight w. If the weight is greater than 1, then the curve is a hyperbola; if the weight equals 1, it's a parabola; and if it is less than 1, it is an ellipse.
Implementation
void conicTo(double x1, double y1, double x2, double y2, double w);