Linux zero mouse values when running via VPN on other PC

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1

Hi,

we’re running Unreal Engine via streaming on an external machine on Linux. UnrealEngine does not seem to pick up the mousemove correctly in its viewport and slate. So e.g. when right-click and move the mouse in a blueprint graph it will move to an indefinite location (as the mouse position delta values are not correct).
Also in the viewport: Rightclick to move just rotates the y axis very fast and always points the camera to look into the sky.
When printing out MouseX and MouseY valus from the blueprint they always return 0.

When printing out GetMouseX in C++ in SceneViewport.cpp I get correct values from SDL.

Now I wanted to ask where in the engine would be other points to look for the error? I guess the mouse is not constantly transferred from my PC to the streamed PC with UnrealEngine running, therefore mouse delta values are probably zero or random values.

Some questions:

  • Where are the hooks for the AxisBindings in UnrealEngine, which read out the SDL mouse position and feed it into the bind
2

Got it figured out. I disabled the SlateApplication.cpp SetHighPrecisionMode.

void FSlateApplication::ProcessReply( const FWidgetPath& CurrentEventPath, const FReply& TheReply, const FWidgetPath* WidgetsUnderMouse, const FPointerEvent* InMouseEvent, const uint32 UserIndex )
{
   ...    
   //PlatformApplication->SetHighPrecisionMouseMode(true, Window->GetNativeWindow());
   ...
}

This mode has caused to Unreal on Linux to use the SDL_MouseMotionEvent which return wrong relative mouse x and y values when working on a remotely connected machine.