[Linux] Return the active window when there's no cursor constraint window

The cursor constraint window is only set by the Editor. In the game
launcher, this function was returning a null window, which makes
`GetSystemCursorPositionNormalized()` unable to determine the cursor
position. This in turn causes mouse input in ImGui to not work.

Fixes #4722, LYN-7491

Signed-off-by: Chris Burel <burelc@amazon.com>

Code/Framework/AzFramework/Platform/Common/Xcb/AzFramework/XcbInputDeviceMouse.cpp

@@ -13,18 +13,68 @@
 
 namespace AzFramework
 {
-    xcb_window_t GetSystemCursorFocusWindow()
+    xcb_window_t GetSystemCursorFocusWindow(xcb_connection_t* connection)
     {
         void* systemCursorFocusWindow = nullptr;
         AzFramework::InputSystemCursorConstraintRequestBus::BroadcastResult(
             systemCursorFocusWindow, &AzFramework::InputSystemCursorConstraintRequests::GetSystemCursorConstraintWindow);
 
-        if (!systemCursorFocusWindow)
+        if (systemCursorFocusWindow)
         {
-            return XCB_NONE;
+            return static_cast<xcb_window_t>(reinterpret_cast<uint64_t>(systemCursorFocusWindow));
         }
 
-        return static_cast<xcb_window_t>(reinterpret_cast<uint64_t>(systemCursorFocusWindow));
+        // EWMH-compliant window managers set the "_NET_ACTIVE_WINDOW" property
+        // of the X server's root window to the currently active window. This
+        // retrieves value of that property.
+
+        // Get the atom for the _NET_ACTIVE_WINDOW property
+        constexpr int propertyNameLength = 18;
+        xcb_generic_error_t* error = nullptr;
+        XcbStdFreePtr<xcb_intern_atom_reply_t> activeWindowAtom {xcb_intern_atom_reply(
+            connection,
+            xcb_intern_atom(connection, /*only_if_exists=*/ 1, propertyNameLength, "_NET_ACTIVE_WINDOW"),
+            &error
+        )};
+        if (!activeWindowAtom || error)
+        {
+            if (error)
+            {
+                AZ_Warning("XcbInput", false, "Retrieving _NET_ACTIVE_WINDOW atom failed : Error code %d", error->error_code);
+                free(error);
+            }
+            return XCB_WINDOW_NONE;
+        }
+
+        // Get the root window
+        const xcb_window_t rootWId = xcb_setup_roots_iterator(xcb_get_setup(connection)).data->root;
+
+        // Fetch the value of the root window's _NET_ACTIVE_WINDOW property
+        XcbStdFreePtr<xcb_get_property_reply_t> property {xcb_get_property_reply(
+            connection,
+            xcb_get_property(
+                /*c=*/connection,
+                /*_delete=*/ 0,
+                /*window=*/rootWId,
+                /*property=*/activeWindowAtom->atom,
+                /*type=*/XCB_ATOM_WINDOW,
+                /*long_offset=*/0,
+                /*long_length=*/1
+            ),
+            &error
+        )};
+
+        if (!property || error)
+        {
+            if (error)
+            {
+                AZ_Warning("XcbInput", false, "Retrieving _NET_ACTIVE_WINDOW atom failed : Error code %d", error->error_code);
+                free(error);
+            }
+            return XCB_WINDOW_NONE;
+        }
+
+        return *static_cast<xcb_window_t*>(xcb_get_property_value(property.get()));
     }
 
     xcb_connection_t* XcbInputDeviceMouse::s_xcbConnection = nullptr;
@@ -36,8 +86,7 @@ namespace AzFramework
         : InputDeviceMouse::Implementation(inputDevice)
         , m_systemCursorState(SystemCursorState::Unknown)
         , m_systemCursorPositionNormalized(0.5f, 0.5f)
-        , m_prevConstraintWindow(XCB_NONE)
-        , m_focusWindow(XCB_NONE)
+        , m_focusWindow(XCB_WINDOW_NONE)
         , m_cursorShown(true)
     {
         XcbEventHandlerBus::Handler::BusConnect();
@@ -271,7 +320,7 @@ namespace AzFramework
         {
             m_systemCursorState = systemCursorState;
 
-            m_focusWindow = GetSystemCursorFocusWindow();
+            m_focusWindow = GetSystemCursorFocusWindow(s_xcbConnection);
 
             HandleCursorState(m_focusWindow, systemCursorState);
         }
@@ -279,50 +328,10 @@ namespace AzFramework
 
     void XcbInputDeviceMouse::HandleCursorState(xcb_window_t window, SystemCursorState systemCursorState)
     {
-        bool confined = false, cursorShown = true;
-        switch (systemCursorState)
-        {
-        case SystemCursorState::ConstrainedAndHidden:
-            {
-                //!< Constrained to the application's main window and hidden
-                confined = true;
-                cursorShown = false;
-            }
-            break;
-        case SystemCursorState::ConstrainedAndVisible:
-            {
-                //!< Constrained to the application's main window and visible
-                confined = true;
-            }
-            break;
-        case SystemCursorState::UnconstrainedAndHidden:
-            {
-                //!< Free to move outside the main window but hidden while inside
-                cursorShown = false;
-            }
-            break;
-        case SystemCursorState::UnconstrainedAndVisible:
-            {
-                //!< Free to move outside the application's main window and visible
-            }
-        case SystemCursorState::Unknown:
-        default:
-            break;
-        }
-
-        // ATTN GetSystemCursorFocusWindow when getting out of the play in editor will return XCB_NONE
-        // We need however the window id to reset the cursor.
-        if (XCB_NONE == window && (confined || cursorShown))
-        {
-            // Reuse the previous window to reset states.
-            window = m_prevConstraintWindow;
-            m_prevConstraintWindow = XCB_NONE;
-        }
-        else
-        {
-            // Remember the window we used to modify cursor and barrier states.
-            m_prevConstraintWindow = window;
-        }
+        const bool confined = (systemCursorState == SystemCursorState::ConstrainedAndHidden) ||
+            (systemCursorState == SystemCursorState::ConstrainedAndVisible);
+        const bool cursorShown = (systemCursorState == SystemCursorState::ConstrainedAndVisible) ||
+            (systemCursorState == SystemCursorState::UnconstrainedAndVisible);
 
         CreateBarriers(window, confined);
         ShowCursor(window, cursorShown);
@@ -336,26 +345,26 @@ namespace AzFramework
     void XcbInputDeviceMouse::SetSystemCursorPositionNormalizedInternal(xcb_window_t window, AZ::Vector2 positionNormalized)
     {
         // TODO Basically not done at all. Added only the basic functions needed.
-        const XcbStdFreePtr<xcb_get_geometry_reply_t> xkbGeometryReply{ xcb_get_geometry_reply(
+        const XcbStdFreePtr<xcb_get_geometry_reply_t> xcbGeometryReply{ xcb_get_geometry_reply(
             s_xcbConnection, xcb_get_geometry(s_xcbConnection, window), nullptr) };
 
-        if (!xkbGeometryReply)
+        if (!xcbGeometryReply)
         {
             return;
         }
 
-        const int16_t x = static_cast<int16_t>(positionNormalized.GetX() * xkbGeometryReply->width);
-        const int16_t y = static_cast<int16_t>(positionNormalized.GetY() * xkbGeometryReply->height);
+        const int16_t x = static_cast<int16_t>(positionNormalized.GetX() * xcbGeometryReply->width);
+        const int16_t y = static_cast<int16_t>(positionNormalized.GetY() * xcbGeometryReply->height);
 
-        xcb_warp_pointer(s_xcbConnection, XCB_NONE, window, 0, 0, 0, 0, x, y);
+        xcb_warp_pointer(s_xcbConnection, XCB_WINDOW_NONE, window, 0, 0, 0, 0, x, y);
 
         xcb_flush(s_xcbConnection);
     }
 
     void XcbInputDeviceMouse::SetSystemCursorPositionNormalized(AZ::Vector2 positionNormalized)
     {
-        const xcb_window_t window = GetSystemCursorFocusWindow();
-        if (XCB_NONE == window)
+        const xcb_window_t window = GetSystemCursorFocusWindow(s_xcbConnection);
+        if (XCB_WINDOW_NONE == window)
         {
             return;
         }
@@ -397,8 +406,8 @@ namespace AzFramework
 
     AZ::Vector2 XcbInputDeviceMouse::GetSystemCursorPositionNormalized() const
     {
-        const xcb_window_t window = GetSystemCursorFocusWindow();
-        if (XCB_NONE == window)
+        const xcb_window_t window = GetSystemCursorFocusWindow(s_xcbConnection);
+        if (XCB_WINDOW_NONE == window)
         {
             return AZ::Vector2::CreateZero();
         }
@@ -549,7 +558,7 @@ namespace AzFramework
                 ProcessRawEventQueues();
                 ResetInputChannelStates();
 
-                m_focusWindow = XCB_NONE;
+                m_focusWindow = XCB_WINDOW_NONE;
 
                 auto* interface = AzFramework::XcbConnectionManagerInterface::Get();
                 interface->SetEnableXInput(interface->GetXcbConnection(), false);

Code/Framework/AzFramework/Platform/Common/Xcb/AzFramework/XcbInputDeviceMouse.h

@@ -161,9 +161,6 @@ namespace AzFramework
         //! Will be true if the xinput2 extension could be initialized.
         static bool m_xInputInitialized;
 
-        //! The window that had focus
-        xcb_window_t m_prevConstraintWindow;
-
         //! The current window that has focus
         xcb_window_t m_focusWindow;
 

Code/Framework/AzFramework/Tests/Platform/Common/Xcb/Actions.h

@@ -60,3 +60,10 @@ ACTION_TEMPLATE(ReturnMalloc,
     *value = T{ p0, p1, p2, p3, p4, p5 };
     return value;
 }
+ACTION_TEMPLATE(ReturnMalloc,
+                HAS_1_TEMPLATE_PARAMS(typename, T),
+                AND_7_VALUE_PARAMS(p0, p1, p2, p3, p4, p5, p6)) {
+    T* value = static_cast<T*>(malloc(sizeof(T)));
+    *value = T{ p0, p1, p2, p3, p4, p5, p6 };
+    return value;
+}

Code/Framework/AzFramework/Tests/Platform/Common/Xcb/MockXcbInterface.cpp

@@ -77,6 +77,37 @@ xcb_void_cookie_t xcb_warp_pointer(
 {
     return MockXcbInterface::Instance()->xcb_warp_pointer(c, src_window, dst_window, src_x, src_y, src_width, src_height, dst_x, dst_y);
 }
+xcb_intern_atom_cookie_t xcb_intern_atom(xcb_connection_t* c, uint8_t only_if_exists, uint16_t name_len, const char* name)
+{
+    return MockXcbInterface::Instance()->xcb_intern_atom(c, only_if_exists, name_len, name);
+}
+xcb_intern_atom_reply_t* xcb_intern_atom_reply(xcb_connection_t* c, xcb_intern_atom_cookie_t cookie, xcb_generic_error_t** e)
+{
+    return MockXcbInterface::Instance()->xcb_intern_atom_reply(c, cookie, e);
+}
+xcb_get_property_cookie_t xcb_get_property(
+    xcb_connection_t* c,
+    uint8_t _delete,
+    xcb_window_t window,
+    xcb_atom_t property,
+    xcb_atom_t type,
+    uint32_t long_offset,
+    uint32_t long_length)
+{
+    return MockXcbInterface::Instance()->xcb_get_property(c, _delete, window, property, type, long_offset, long_length);
+}
+xcb_get_property_reply_t* xcb_get_property_reply(xcb_connection_t* c, xcb_get_property_cookie_t cookie, xcb_generic_error_t** e)
+{
+    return MockXcbInterface::Instance()->xcb_get_property_reply(c, cookie, e);
+}
+void* xcb_get_property_value(const xcb_get_property_reply_t* R)
+{
+    return MockXcbInterface::Instance()->xcb_get_property_value(R);
+}
+uint32_t xcb_generate_id(xcb_connection_t *c)
+{
+    return MockXcbInterface::Instance()->xcb_generate_id(c);
+}
 
 // ----------------------------------------------------------------------------
 // xcb-xkb
@@ -181,6 +212,32 @@ xcb_void_cookie_t xcb_xfixes_hide_cursor_checked(xcb_connection_t* c, xcb_window
 {
     return MockXcbInterface::Instance()->xcb_xfixes_hide_cursor_checked(c, window);
 }
+xcb_void_cookie_t xcb_xfixes_delete_pointer_barrier_checked(xcb_connection_t* c, xcb_xfixes_barrier_t barrier)
+{
+    return MockXcbInterface::Instance()->xcb_xfixes_delete_pointer_barrier_checked(c, barrier);
+}
+xcb_translate_coordinates_cookie_t xcb_translate_coordinates(xcb_connection_t* c, xcb_window_t src_window, xcb_window_t dst_window, int16_t src_x, int16_t src_y)
+{
+    return MockXcbInterface::Instance()->xcb_translate_coordinates(c, src_window, dst_window, src_x, src_y);
+}
+xcb_translate_coordinates_reply_t* xcb_translate_coordinates_reply(xcb_connection_t* c, xcb_translate_coordinates_cookie_t cookie, xcb_generic_error_t** e)
+{
+    return MockXcbInterface::Instance()->xcb_translate_coordinates_reply(c, cookie, e);
+}
+xcb_void_cookie_t xcb_xfixes_create_pointer_barrier_checked(
+    xcb_connection_t* c,
+    xcb_xfixes_barrier_t barrier,
+    xcb_window_t window,
+    uint16_t x1,
+    uint16_t y1,
+    uint16_t x2,
+    uint16_t y2,
+    uint32_t directions,
+    uint16_t num_devices,
+    const uint16_t* devices)
+{
+    return MockXcbInterface::Instance()->xcb_xfixes_create_pointer_barrier_checked(c, barrier, window, x1, y1, x2, y2, directions, num_devices, devices);
+}
 
 // ----------------------------------------------------------------------------
 // xcb-xinput

Code/Framework/AzFramework/Tests/Platform/Common/Xcb/MockXcbInterface.h

@@ -82,6 +82,19 @@ public:
         uint16_t src_height,
         int16_t dst_x,
         int16_t dst_y));
+    MOCK_CONST_METHOD4(xcb_intern_atom, xcb_intern_atom_cookie_t(xcb_connection_t* c, uint8_t only_if_exists, uint16_t name_len, const char* name));
+    MOCK_CONST_METHOD3(xcb_intern_atom_reply, xcb_intern_atom_reply_t*(xcb_connection_t* c, xcb_intern_atom_cookie_t cookie, xcb_generic_error_t** e));
+    MOCK_CONST_METHOD7(xcb_get_property, xcb_get_property_cookie_t(
+        xcb_connection_t* c,
+        uint8_t _delete,
+        xcb_window_t window,
+        xcb_atom_t property,
+        xcb_atom_t type,
+        uint32_t long_offset,
+        uint32_t long_length));
+    MOCK_CONST_METHOD3(xcb_get_property_reply, xcb_get_property_reply_t*(xcb_connection_t* c, xcb_get_property_cookie_t cookie, xcb_generic_error_t** e));
+    MOCK_CONST_METHOD1(xcb_get_property_value, void*(const xcb_get_property_reply_t* R));
+    MOCK_CONST_METHOD1(xcb_generate_id, uint32_t(xcb_connection_t *c));
 
     // xcb-xkb
     MOCK_CONST_METHOD3(xcb_xkb_use_extension, xcb_xkb_use_extension_cookie_t(xcb_connection_t* c, uint16_t wantedMajor, uint16_t wantedMinor));
@@ -108,6 +121,20 @@ public:
     MOCK_CONST_METHOD3(xcb_xfixes_query_version_reply, xcb_xfixes_query_version_reply_t*(xcb_connection_t* c, xcb_xfixes_query_version_cookie_t cookie, xcb_generic_error_t** e));
     MOCK_CONST_METHOD2(xcb_xfixes_show_cursor_checked, xcb_void_cookie_t(xcb_connection_t* c, xcb_window_t window));
     MOCK_CONST_METHOD2(xcb_xfixes_hide_cursor_checked, xcb_void_cookie_t(xcb_connection_t* c, xcb_window_t window));
+    MOCK_CONST_METHOD2(xcb_xfixes_delete_pointer_barrier_checked, xcb_void_cookie_t(xcb_connection_t* c, xcb_xfixes_barrier_t barrier));
+    MOCK_CONST_METHOD5(xcb_translate_coordinates, xcb_translate_coordinates_cookie_t(xcb_connection_t* c, xcb_window_t src_window, xcb_window_t dst_window, int16_t src_x, int16_t src_y));
+    MOCK_CONST_METHOD3(xcb_translate_coordinates_reply, xcb_translate_coordinates_reply_t*(xcb_connection_t* c, xcb_translate_coordinates_cookie_t cookie, xcb_generic_error_t** e));
+    MOCK_CONST_METHOD10(xcb_xfixes_create_pointer_barrier_checked, xcb_void_cookie_t(
+        xcb_connection_t* c,
+        xcb_xfixes_barrier_t barrier,
+        xcb_window_t window,
+        uint16_t x1,
+        uint16_t y1,
+        uint16_t x2,
+        uint16_t y2,
+        uint32_t directions,
+        uint16_t num_devices,
+        const uint16_t* devices));
 
     // xcb-xinput
     MOCK_CONST_METHOD3(xcb_input_xi_query_version, xcb_input_xi_query_version_cookie_t(xcb_connection_t* c, uint16_t major_version, uint16_t minor_version));

Code/Framework/AzFramework/Tests/Platform/Common/Xcb/XcbInputDeviceMouseTests.cpp

@@ -28,7 +28,10 @@ namespace AzFramework
     public:
         void SetUp() override
         {
+            using testing::Eq;
+            using testing::Field;
             using testing::Return;
+            using testing::StrEq;
             using testing::_;
 
             XcbBaseTestFixture::SetUp();
@@ -61,6 +64,37 @@ namespace AzFramework
                     /*major_version=*/(uint16_t)2,
                     /*minor_version=*/(uint16_t)2
                 ));
+
+            // Set the default focus window
+            EXPECT_CALL(m_interface, xcb_intern_atom(&m_connection, 1, 18, StrEq("_NET_ACTIVE_WINDOW")))
+                .WillRepeatedly(Return(xcb_intern_atom_cookie_t{/*.sequence=*/ 1}));
+            ON_CALL(m_interface, xcb_intern_atom_reply(&m_connection, Field(&xcb_intern_atom_cookie_t::sequence, Eq(1)), _))
+                .WillByDefault(ReturnMalloc<xcb_intern_atom_reply_t>(
+                    /*response_type=*/(uint8_t)XCB_INTERN_ATOM,
+                    /*pad0=*/(uint8_t)0,
+                    /*sequence=*/(uint16_t)1,
+                    /*length=*/0u,
+                    /*xcb_atom_t=*/s_netActiveWindowAtom
+                ));
+            ON_CALL(m_interface, xcb_get_property(&m_connection, 0, s_rootWindow, s_netActiveWindowAtom, XCB_ATOM_WINDOW, 0, 1))
+                .WillByDefault(Return(xcb_get_property_cookie_t{/*.sequence=*/ s_getActiveWindowPropertySequence}));
+            ON_CALL(m_interface, xcb_get_property_reply(&m_connection, Field(&xcb_get_property_cookie_t::sequence, Eq(s_getActiveWindowPropertySequence)), _))
+                .WillByDefault(ReturnMalloc<xcb_get_property_reply_t>(
+                    /*response_type=*/(uint8_t)XCB_GET_PROPERTY,
+                    /*format=*/(uint8_t)0,
+                    /*sequence=*/(uint16_t)s_getActiveWindowPropertySequence,
+                    /*length=*/0u,
+                    /*type=*/XCB_ATOM_WINDOW,
+                    /*bytes_after=*/0u,
+                    /*value_len=*/1u
+                ));
+            ON_CALL(m_interface, xcb_get_property_value(Field(&xcb_get_property_reply_t::sequence, Eq(s_getActiveWindowPropertySequence))))
+                .WillByDefault(Return(const_cast<xcb_window_t*>(&s_nullWindow)));
+
+            ON_CALL(m_interface, xcb_get_geometry(&m_connection, _))
+                .WillByDefault(Return(xcb_get_geometry_cookie_t{/*.sequence=*/1}));
+            ON_CALL(m_interface, xcb_get_geometry_reply(&m_connection, Field(&xcb_get_geometry_cookie_t::sequence, Eq(1)), _))
+                .WillByDefault(ReturnMalloc<xcb_get_geometry_reply_t>(s_defaultWindowGeometry));
         }
 
         void PumpApplication()
@@ -73,10 +107,13 @@ namespace AzFramework
     protected:
         static constexpr inline uint8_t s_xinputMajorOpcode = 131;
         static constexpr inline xcb_window_t s_rootWindow = 1;
+        static constexpr inline xcb_window_t s_nullWindow = XCB_WINDOW_NONE;
         static constexpr inline xcb_input_device_id_t s_virtualCorePointerId = 2;
         static constexpr inline xcb_input_device_id_t s_physicalPointerDeviceId = 3;
         static constexpr inline uint16_t s_screenWidthInPixels = 3840;
         static constexpr inline uint16_t s_screenHeightInPixels = 2160;
+        static constexpr inline uint16_t s_getActiveWindowPropertySequence = 2160;
+        static constexpr inline xcb_atom_t s_netActiveWindowAtom = 1;
         static constexpr inline xcb_setup_t s_xcbSetup{
             /*.status=*/1,
             /*.pad0=*/0,
@@ -109,6 +146,19 @@ namespace AzFramework
             /*.present=*/1,
             /*.major_opcode=*/s_xinputMajorOpcode,
         };
+        static constexpr inline xcb_get_geometry_reply_t s_defaultWindowGeometry{
+            /*.response_type=*/XCB_GET_GEOMETRY,
+            /*.depth=*/0,
+            /*.sequence=*/1,
+            /*.length=*/0,
+            /*.root=*/s_rootWindow,
+            /*.x=*/100,
+            /*.y=*/100,
+            /*.width=*/100,
+            /*.height=*/100,
+            /*.border_width=*/3,
+            /*.pad0[2]=*/{},
+        };
         XcbTestApplication m_application{
             /*enabledGamepadsCount=*/0,
             /*keyboardEnabled=*/false,
@@ -398,4 +448,98 @@ namespace AzFramework
         EXPECT_THAT(xMotionChannel->GetValue(), FloatEq(0.0f));
         EXPECT_THAT(yMotionChannel->GetValue(), FloatEq(0.0f));
     }
+
+    struct GetCursorPositionParam
+    {
+        int16_t m_x;
+        int16_t m_y;
+    };
+
+    class XcbGetSystemCursorPositionTests
+        : public XcbInputDeviceMouseTests
+        , public testing::WithParamInterface<GetCursorPositionParam>
+    {
+    };
+
+    TEST_P(XcbGetSystemCursorPositionTests, GetSystemCursorPositionNormalizedReturnsCorrectValue)
+    {
+        using testing::Eq;
+        using testing::Field;
+        using testing::Return;
+        using testing::_;
+
+        xcb_window_t focusWindow = 42;
+        const xcb_query_pointer_reply_t queryPointerReply{
+            /*.response_type=*/XCB_QUERY_POINTER,
+            /*.same_screen=*/1,
+            /*.sequence=*/0,
+            /*.length=*/1,
+            /*.root=*/s_rootWindow,
+            /*.child=*/focusWindow,
+            /*.root_x=*/static_cast<int16_t>(GetParam().m_x + s_defaultWindowGeometry.x),
+            /*.root_y=*/static_cast<int16_t>(GetParam().m_y + s_defaultWindowGeometry.y),
+            /*.win_x=*/GetParam().m_x,
+            /*.win_y=*/GetParam().m_y,
+            /*.mask=*/{},
+            /*.pad0[2]=*/{},
+        };
+
+        // Querying the root window's pointer gives its absolute value
+        const xcb_query_pointer_reply_t rootWindowQueryPointerReply{
+            /*.response_type=*/XCB_QUERY_POINTER,
+            /*.same_screen=*/1,
+            /*.sequence=*/0,
+            /*.length=*/1,
+            /*.root=*/s_rootWindow,
+            /*.child=*/s_rootWindow,
+            /*.root_x=*/static_cast<int16_t>(GetParam().m_x + s_defaultWindowGeometry.x),
+            /*.root_y=*/static_cast<int16_t>(GetParam().m_y + s_defaultWindowGeometry.y),
+            /*.win_x=*/static_cast<int16_t>(GetParam().m_x + s_defaultWindowGeometry.x),
+            /*.win_y=*/static_cast<int16_t>(GetParam().m_y + s_defaultWindowGeometry.y),
+            /*.mask=*/{},
+            /*.pad0[2]=*/{},
+        };
+
+        EXPECT_CALL(m_interface, xcb_get_property_value(Field(&xcb_get_property_reply_t::sequence, Eq(s_getActiveWindowPropertySequence))))
+            .WillRepeatedly(Return(&focusWindow));
+
+        EXPECT_CALL(m_interface, xcb_query_pointer(&m_connection, focusWindow))
+            .WillRepeatedly(Return(xcb_query_pointer_cookie_t{/*.sequence=*/1}));
+        EXPECT_CALL(m_interface, xcb_query_pointer_reply(&m_connection, Field(&xcb_query_pointer_cookie_t::sequence, 1), _))
+            .WillRepeatedly(ReturnMalloc<xcb_query_pointer_reply_t>(queryPointerReply));
+
+        EXPECT_CALL(m_interface, xcb_query_pointer(&m_connection, s_rootWindow))
+            .WillRepeatedly(Return(xcb_query_pointer_cookie_t{/*.sequence=*/2}));
+        EXPECT_CALL(m_interface, xcb_query_pointer_reply(&m_connection, Field(&xcb_query_pointer_cookie_t::sequence, 2), _))
+            .WillRepeatedly(ReturnMalloc<xcb_query_pointer_reply_t>(rootWindowQueryPointerReply));
+
+        m_application.Start();
+        InputSystemCursorRequestBus::Event(
+            InputDeviceMouse::Id,
+            &InputSystemCursorRequests::SetSystemCursorState,
+            SystemCursorState::ConstrainedAndHidden);
+
+        AZ::Vector2 systemCursorPositionNormalized = AZ::Vector2::CreateZero();
+        InputSystemCursorRequestBus::EventResult(
+            systemCursorPositionNormalized,
+            InputDeviceMouse::Id,
+            &InputSystemCursorRequests::GetSystemCursorPositionNormalized);
+
+        EXPECT_THAT(systemCursorPositionNormalized, ::testing::AllOf(
+            testing::Property(&AZ::Vector2::GetX, testing::FloatEq(static_cast<float>(GetParam().m_x) / s_defaultWindowGeometry.width)),
+            testing::Property(&AZ::Vector2::GetY, testing::FloatEq(static_cast<float>(GetParam().m_y) / s_defaultWindowGeometry.height))
+        ));
+    }
+
+    INSTANTIATE_TEST_CASE_P(
+        AllPointerPositions,
+        XcbGetSystemCursorPositionTests,
+        testing::Values(
+            // Default mocked window geometry sets width and height to 100, all
+            // parameter values should be within [0, 100)
+            GetCursorPositionParam{ 50, 50 },
+            GetCursorPositionParam{ 25, 25 },
+            GetCursorPositionParam{ 0, 100 }
+        )
+    );
 } // namespace AzFramework