Since REGION16 uses unsigned values, when appWindow->x or appWindow->y
is negative, the region will have a very large left or top value.
Avoid this problem by clamping to 0 before casting to an unsigned value.
Remove use of the visibleOffset, this completely breaks the display of all windows except for the main application window. Instead,
just maintain a local offset correction of the windowOffset.
Apply workaround to determining the workArea for remote app mode.
1. Linked Window Manager Maximize/Minimize and Restore operations to those from the Server Rail Window so that they are in sync
2. Enable things like "CTRL-ALT-DELETE" and "WindowsKey-L" to show the full desktop window again since the desktop is not actively monitored since
this was still trying to draw to the rail window without updating the size of the window to accomodate the full workspace area.
3. Changed local window coordinates to be based on the visibileOffsetX/Y- while moving server window based on WindowOffsetX/Y. I have seen various issues regarding this when trying to use a maximized window where this is a disconnect between local window coordinates and remote window coordinates. This change clears these things up.
4. Commented the XShapeCombineRectangles calls - this can cause issues where the entire window is not visible and it does not currently play well with the changes from #3. The gain here is greater than the loss.
5. Draw the initial workspace correctly when running across multiple monitors. The correct size was always used, but the window was only starting on the current monitor and thus could draw the window off of the viewable area.
Known Issues:
Although the changes for #2 worked well in the stable branch that I developed from - the desktop window shown once the rail windows are destroyed does not respond to input unless I minimize/restore the window. Once the window starts responding to input - you can hit cancel to close the desktop window and return to your rail windows again(or launch task manager, etc.). This is still a big step in the right direction as xfreerdp is now correctly acting when the rail server stops Actively Monitoring the desktop.
XShapeCombineRectangles needs to be revisited, most windows applications will give you a rectangular window anyways.
