WindowsForms touch functionality missing

[rapmue]

IF BUG, INCLUDE THIS PART:

Steps to reproduce

1. Run the WindowsForms example
2. Use a multitouch screen on Windows 10
3. Try to zoom / pan on a plot

Platform: Windows 10 / WindowsForms
.NET version: 4.5.2

Expected behaviour

Zooming and paning should work out of the box.

Actual behaviour

The zoom gesture is stuttering or not working at all. Paning is only available via translated touch gestures to mouse events.

What I have done already

1. I checked and found that in WindowsForms the Windowsmessages are not intercepted. I made a quick implementation and provided all information of the touch event to the TouchManipulator.

2. The TouchManipulator only works when the TouchTrackerManipulator is disabled at PlotController level (also mentioned in Pan and Zoom not working oxyplot-xamarin#62)

Number 1 is already solved, but the issue with a second touch manipulator, which overrides the first manipulator should be discussed. Mouse events are different with a modifier, where touch gestures aren't. There are a few different solutions to catch touch gestures. One solution is to handle WindowsMultitouch gestures. There are only 5 gestures, i.e. "zoom", "pan", "rotate", "two finger tap" and "press and tap".
The other solution could be to use the RAW touch points like in this example. The second approach needs a little bit more to work, but has more flexibility when it comes to tracking etc.

[rapmue]

Maybe the touch manipulator is also not working on other plattforms (#1197) because of the behaviour of overwriting the normal touchmanipulator?