title: Drawing rounded/movable area over image
body: <p>I would like to draw rounded area and points over a photo.
  I decided to do it with a svg which is simplier to make it resizable and movable.</p>
  <p>But, from a list of points I do not have an area which go through all points.
  I used the Quadratic Bezier CurveTo, but I am not able to find the mathematic formula to give the the &quot;Q parameter&quot; the values to calculate the control point to go from A to C passing by B.
  For the moment, when the angle is too high, the line &quot;turn&quot; before the point, but i would like to go touch the point.</p>
  <p><a href="https://i.stack.imgur.com/79MkI.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/79MkI.png" alt="enter image description here" /></a><a href="https://i.stack.imgur.com/cr37X.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/cr37X.png" alt="enter image description here" /></a></p>