Method DoDragDropWayland

Source/Engine/Platform/SDL/SDLPlatform.Linux.cpp:664–739

}

DragDropEffect Window::DoDragDropWayland(const StringView& data, Window* dragSourceWindow, Float2 dragOffset)
{
    // HACK: For drag-and-drop, we need to run another event queue in a separate thread to avoid racing issues
    // while SDL is dispatching the main Wayland event queue when receiving the data offer from us.

    Engine::OnDraw();

    if (WaylandImpl::DraggingActive)
        LOG(Fatal, "Previous drag and drop operation was not finished");

    // Read the latest serial code from mouse event, and check if we are still holding the mouse before committing
    auto dragSerial = Platform::AtomicRead(&WaylandImpl::Serial);
    SDLPlatform::Tick(); // Handle events to check for serial changes

    if (!Input::Mouse->GetButton(MouseButton::Left) ||
        dragSerial == 0 ||
        dragSerial != Platform::AtomicRead(&WaylandImpl::Serial))
    {
        // The mouse up event was ignored earlier, release the button now
        Input::Mouse->OnMouseUp(Platform::GetMousePosition(), MouseButton::Left, this);
        
        return DragDropEffect::None;
    }
    
    WaylandImpl::DraggingActive = true;
    WaylandImpl::DraggingData = StringView(data.Get(), data.Length());
    WaylandImpl::DragOverFlag = 0;

    auto task = New<WaylandImpl::DragDropJob>();
    task->Window = this;
    task->DragSourceWindow = dragSourceWindow; // Needs to be the parent window when dragging a tab to window
    task->DragOffset = dragOffset;
    task->DragSerial = dragSerial;
    Task::StartNew(task);
    
    while (Platform::AtomicRead(&task->StartFlag) == 0)
    {
        SDLPlatform::Tick();
        Platform::Sleep(1);
    }

    while (Platform::AtomicRead(&WaylandImpl::DragOverFlag) == 0)
    {
        SDLPlatform::Tick();
        Engine::OnUpdate(); // For docking updates
        Engine::OnDraw();

        // The window needs to be finished showing up before we can start dragging it
        if (IsVisible() && Platform::AtomicRead(&task->WaitFlag) == 0)
            Platform::AtomicStore(&task->WaitFlag, 1);
        
        if (!WaylandImpl::DraggingWindow && !Input::Mouse->GetButton(MouseButton::Left))
        {
            // Abort in case the dragging was interrupted before receiving any data offers
            Platform::AtomicStore(&task->ExitFlag, 1);
            break;
        }