This restores basic support for Intel AMT servers. They refuse clients
that request more than 16 bits per pixels, so implement a fallback
in just the "Raw" encoding.
The VNC protocol can't handle different deltas or speeds for a mouse
wheel event. When using a device that sends a lot of small mouse wheel
events, instead of fewer larger steps, the effect was that mouse wheel
scrolling was way to sensitive.
This patch looks at the delta of wheel events and doesn't send events
until the combined delta has passed a threshold. Single events that
doesn't pass the threshold get sent after a timeout in order to not
loose any events.
Fixes#577.
Servers will assume that a scan code is present if this message type
is used, so fall back to the standard key event message if we don't
know the scan code.
IE and Edge have some corner cases (e.g. Ctrl+key) where we get
insufficient information in the keydown event, and we never get
a keypress event. Try to make a guess of the key in those cases.
iOS sends decent key down events, but junk key up events when a
hardware keyboard is used. This confuses the key tracking as a
corresponding release is then never detected. To work around this
we'll treat the hardware keyboard like the virtual ones and send
the key release right away.
It doesn't need to be this general as the issue is mostly about
Windows. Also use the same modifier shuffle that RealVNC and
TigerVNC uses to get macOS working well.
The fields provided cannot tell us if it is the left or right
version of the key that's pressed, so they are inherently unreliable.
It is also not a huge problem in practice as we'll get in sync on
the next press or release of the modifier.
Look up keys that are independent of layout and state first,
followed by keys that are only mild variations in layouts.
This is more robust as there might be multiple physical keys
generating the same symbols, and Keysyms don't map directly to
Unicode in all cases.
At the same time switch over to using the modern, standardised
'code' field for lookup.
Use the more modern 'key' field, and remove some legacy fallbacks
that are no longer required. This also removes the "stall" mechanism
as it is not needed with current browsers.
Setting a style to null does restore it in FF, Chrome, Safari and Edge.
But it does not work in Internet Explorer. The proper way to restore to
default values is to set it to the empty string. This works in all
browsers. Fixes issue #808.
Samuel Mannehed
Pierre Ossman
shaneharris