Rewrite the Wpf control and version bump to 3.0.0

[jeremyVignelles]

Motivation

There are many Wpf bugs that are caused by the airspace issue #296 .

The Wpf control as it is now is just a wrapper around the WinForms control, which can be easily reproduced.

User are asking for a Wpf control that is not dependant on a WinForms component ( see #249 ).

Options that were available

Keep things as-is

Not a good option in my opinion, because many issues would have been left unanswered.

Try to use DirectX

Wpf is based on DirectX, it seemed to be a good option at first. However, using DirectX from WPF is really hard and suffers from too many bugs ( see sharpdx/SharpDX#599 (comment) ) . Most of the time, people are suggesting to use WinForms to use DirectX with best performance, but that would bring us no gain over the "keep as-is" method.

Moreover, things are not ready in libvlc to use DirectX from outside in the classic build (winrt build are available, but not really applicable for us...)

Using a Wpf bitmap

This is the solution that have been chosen. Warnings are there in the libvlc documentation to discourage the use of this method, because there is a copy of buffers involved, which slows down the rendering and consumes more resources.

However, this is a technique that have been used in older version of Vlc.DotNet and in other bindings like Meta.Vlc. It provides a good experience for WPF developpers, since an ImageSource can be used in a ImageBrush and painted everywhere !

If performance is critical, it is still possible to use the WinForms control in WPF.

What needs to be done

• Implement the Wpf control
• Make the "default" Wpf control and the ImageSource two separate things (one may want to use it without displaying the full video)
• Add the ability to pass mouse events to libvlc : not possible with current version of libvlc (3.0.0).
• Make sure that the API is correct for most of the use cases : Looks correct to me, we'll see in develop
• Update documentation
• Explain how to choose a Wpf component ( WPF for better UX, WinForms for performance )