Quadratic Bezier Curves Demo
This demo shows a path made up of four quadratic Bezier curve segments. Each segment is defined by its two endpoints and by a single control point. The endpoints are black disks. The control points are blue squares. A control point determines the tangent lines at both endpoints of the curve segment that it controls.
You can drag the endpoints and the control points!
It is possible to make a smooth curve, that is one where the segments join smoothly at each endpoint instead of making a corner. You just need to make sure that the endpoint that joins two segments lies on the line segment defined by the two control points for those segments. Try it!
The "Hide Controls" checkbox will hide the control points and endpoints so that you can see curve better. You can't edit the curve while Hide Controls is checked.