Wrong explanatory picture for Context2D arcTo function

In documentation the picture for function arcTo(x1, real y1, real x2, real y2, real radius) is incorrect, should be something like this:

Also W3C's 2D Context Standard for arcTo() is really clear describe arcTo
https://www.w3.org/TR/2dcontext/#dom-context-2d-arcto
it would be nice if such description was added to qt documentation.