Add support for more than 4 joystick buttons under MSW

Use polling thread instead of relying on MM_JOYXXX events to allow
receiving events from all the supported buttons.

See https://github.com/wxWidgets/wxWidgets/pull/942

Closes #1142.

docs/changes.txt

@@ -141,6 +141,7 @@ wxMSW:
 - Add experimental support for Windows 10/ARM64 platform (Simon Rozman).
 - Fix hang after clearing wxTAB_TRAVERSAL style on a window with children.
 - Fix handling of AUX2 mouse button events (Timon Rozmanrylz).
+- Implement support for more than 4 joystick buttons (Mick Phillips).
 - Fix saving/restoring window position for maximized windows.
 - Fix stack corruption when using wxStackWalker (srfisk).
 - Fix positioning windows at positions >= SHORT_MAX (Cătălin Răceanu).

include/wx/msw/joystick.h

@@ -13,6 +13,8 @@
 
 #include "wx/event.h"
 
+class wxJoystickThread;
+
 class WXDLLIMPEXP_ADV wxJoystick: public wxObject
 {
   wxDECLARE_DYNAMIC_CLASS(wxJoystick);
@@ -22,6 +24,7 @@ public:
    */
 
   wxJoystick(int joystick = wxJOYSTICK1);
+  virtual ~wxJoystick();
 
   // Attributes
   ////////////////////////////////////////////////////////////////////////////
@@ -85,6 +88,7 @@ public:
 
 protected:
   int                   m_joystick;
+  wxJoystickThread*     m_thread;
 };
 
 #endif

src/msw/joystick.cpp

@@ -37,8 +37,129 @@
 
 #include <regstr.h>
 
+// Use optimised count trailing zeros where available.
+static int wxCtz(unsigned x)
+{
+    wxCHECK_MSG(x > 0, 0, "Undefined for x == 0.");
+#ifdef __GNUC__
+   return __builtin_ctz(x);
+#else
+   int n;
+   n = 1;
+   if ((x & 0x0000FFFF) == 0) {n = n +16; x = x >>16;}
+   if ((x & 0x000000FF) == 0) {n = n + 8; x = x >> 8;}
+   if ((x & 0x0000000F) == 0) {n = n + 4; x = x >> 4;}
+   if ((x & 0x00000003) == 0) {n = n + 2; x = x >> 2;}
+   return n - (x & 1);
+#endif
+}
+
+
+enum {
+    wxJS_AXIS_X = 0,
+    wxJS_AXIS_Y,
+    wxJS_AXIS_Z,
+    wxJS_AXIS_RUDDER,
+    wxJS_AXIS_U,
+    wxJS_AXIS_V,
+
+    wxJS_AXIS_MAX = 32767,
+    wxJS_AXIS_MIN = -32767,
+    wxJS_MAX_AXES = 6,      // WinMM supports up to 6 axes.
+    wxJS_MAX_BUTTONS = 32,  // WinMM supports up to 32 buttons.
+};
+
 wxIMPLEMENT_DYNAMIC_CLASS(wxJoystick, wxObject);
 
+////////////////////////////////////////////////////////////////////////////
+// Background thread for reading the joystick device
+////////////////////////////////////////////////////////////////////////////
+
+class wxJoystickThread : public wxThread
+{
+public:
+    explicit wxJoystickThread(int joystick);
+    void* Entry() wxOVERRIDE;
+    void SetPolling(wxWindow* win, int pollingFreq)
+    {
+        m_catchwin = win;
+        m_polling = pollingFreq;
+    };
+
+
+private:
+    void      SendEvent(wxEventType type, long ts, int change = 0);
+    int       m_joystick;
+    UINT      m_buttons;
+    wxWindow* m_catchwin;
+    int       m_polling;
+    JOYINFO   m_joyInfo;
+    JOYINFO   m_lastJoyInfo;
+};
+
+
+wxJoystickThread::wxJoystickThread(int joystick)
+    : m_joystick(joystick),
+      m_buttons(0),
+      m_catchwin(NULL),
+      m_polling(0),
+      m_joyInfo(),
+      m_lastJoyInfo()
+{
+}
+
+void wxJoystickThread::SendEvent(wxEventType type, long ts, int change)
+{
+    wxJoystickEvent joystickEvent(type, (int)m_buttons, m_joystick, change);
+
+    joystickEvent.SetTimestamp(ts);
+    joystickEvent.SetPosition(wxPoint( (int)m_joyInfo.wXpos, (int)m_joyInfo.wYpos) );
+    joystickEvent.SetZPosition( (int)m_joyInfo.wZpos );
+    joystickEvent.SetEventObject(m_catchwin);
+
+    if (m_catchwin)
+        m_catchwin->GetEventHandler()->ProcessThreadEvent(joystickEvent);
+}
+
+void* wxJoystickThread::Entry()
+{
+    joyGetPos(m_joystick, &m_lastJoyInfo);
+
+    while (!TestDestroy())
+    {
+        Sleep(m_polling);
+        long ts = GetTickCount();
+
+        joyGetPos(m_joystick, &m_joyInfo);
+        m_buttons = m_joyInfo.wButtons;
+        UINT delta = m_buttons ^ m_lastJoyInfo.wButtons;
+        UINT deltaUp = delta & !m_buttons;
+        UINT deltaDown = delta & m_buttons;
+
+        // Use count trailing zeros to determine which button changed.
+        // Was using JOYINFOEX.dwButtons, because the docs state this is
+        // "Current button number that is pressed.", but it turns out
+        // it is the *total* number of buttons pressed.
+        if (deltaUp)
+            SendEvent(wxEVT_JOY_BUTTON_UP, ts, wxCtz(deltaUp)+1);
+        if (deltaDown)
+            SendEvent(wxEVT_JOY_BUTTON_DOWN, ts, wxCtz(deltaDown)+1);
+
+        if ((m_joyInfo.wXpos != m_lastJoyInfo.wXpos) ||
+            (m_joyInfo.wYpos != m_lastJoyInfo.wYpos) ||
+            (m_joyInfo.wZpos != m_lastJoyInfo.wZpos)   )
+        {
+            SendEvent(wxEVT_JOY_MOVE, ts);
+        }
+
+        m_lastJoyInfo = m_joyInfo;
+    }
+
+    return NULL;
+}
+
+
+
 // Attributes
 ////////////////////////////////////////////////////////////////////////////
 
@@ -62,6 +183,8 @@ wxJoystick::wxJoystick(int joystick)
             {
                 /* Found the one we want, store actual OS id and return */
                 m_joystick = i;
+                m_thread = new wxJoystickThread(m_joystick);
+                m_thread->Run();
                 return;
             }
             joystick --;
@@ -73,6 +196,15 @@ wxJoystick::wxJoystick(int joystick)
     return;
 }
 
+
+wxJoystick::~wxJoystick()
+{
+    ReleaseCapture();
+    if (m_thread)
+        m_thread->Delete();  // It's detached so it will delete itself
+}
+
+
 wxPoint wxJoystick::GetPosition() const
 {
     JOYINFO joyInfo;
@@ -256,7 +388,7 @@ int wxJoystick::GetMovementThreshold() const
     MMRESULT res = joyGetThreshold(m_joystick, & thresh);
     if (res == JOYERR_NOERROR )
     {
-        return thresh;
+        return (int)thresh;
     }
     else
         return 0;
@@ -264,8 +396,7 @@ int wxJoystick::GetMovementThreshold() const
 
 void wxJoystick::SetMovementThreshold(int threshold)
 {
-    UINT thresh = threshold;
+    joySetThreshold(m_joystick, (UINT)threshold);
-    joySetThreshold(m_joystick, thresh);
 }
 
 // Capabilities
@@ -578,26 +709,28 @@ bool wxJoystick::HasPOVCTS() const
         return ((joyCaps.wCaps & JOYCAPS_POVCTS) == JOYCAPS_POVCTS);
 }
 
+////////////////////////////////////////////////////////////////////////////
 // Operations
 ////////////////////////////////////////////////////////////////////////////
 
 bool wxJoystick::SetCapture(wxWindow* win, int pollingFreq)
 {
-#ifdef __WXMSW__
+    if (m_thread)
-    BOOL changed = (pollingFreq == 0);
+    {
-    MMRESULT res = joySetCapture((HWND) win->GetHWND(), m_joystick, pollingFreq, changed);
+        m_thread->SetPolling(win, pollingFreq);
-    return (res == JOYERR_NOERROR);
+        return true;
-#else
+    }
-    wxUnusedVar(win);
-    wxUnusedVar(pollingFreq);
     return false;
-#endif
 }
 
 bool wxJoystick::ReleaseCapture()
 {
-    MMRESULT res = joyReleaseCapture(m_joystick);
+    if (m_thread)
-    return (res == JOYERR_NOERROR);
+    {
+        m_thread->SetPolling(NULL, 0);
+        return true;
+    }
+    return false;
 }
 
 #endif // wxUSE_JOYSTICK

src/msw/window.cpp

@@ -3133,19 +3133,6 @@ wxWindowMSW::MSWHandleMessage(WXLRESULT *result,
             }
             break;
 
-        case MM_JOY1MOVE:
-        case MM_JOY2MOVE:
-        case MM_JOY1ZMOVE:
-        case MM_JOY2ZMOVE:
-        case MM_JOY1BUTTONDOWN:
-        case MM_JOY2BUTTONDOWN:
-        case MM_JOY1BUTTONUP:
-        case MM_JOY2BUTTONUP:
-            processed = HandleJoystickEvent(message,
-                                            LOWORD(lParam),
-                                            HIWORD(lParam),
-                                            wParam);
-            break;
 
         case WM_COMMAND:
             {
@@ -6162,92 +6149,6 @@ bool wxWindowMSW::HandleClipboardEvent(WXUINT nMsg)
     return HandleWindowEvent(evt);
 }
 
-// ---------------------------------------------------------------------------
-// joystick
-// ---------------------------------------------------------------------------
-
-bool wxWindowMSW::HandleJoystickEvent(WXUINT msg, int x, int y, WXUINT flags)
-{
-    int change = 0;
-    if ( flags & JOY_BUTTON1CHG )
-        change = wxJOY_BUTTON1;
-    if ( flags & JOY_BUTTON2CHG )
-        change = wxJOY_BUTTON2;
-    if ( flags & JOY_BUTTON3CHG )
-        change = wxJOY_BUTTON3;
-    if ( flags & JOY_BUTTON4CHG )
-        change = wxJOY_BUTTON4;
-
-    int buttons = 0;
-    if ( flags & JOY_BUTTON1 )
-        buttons |= wxJOY_BUTTON1;
-    if ( flags & JOY_BUTTON2 )
-        buttons |= wxJOY_BUTTON2;
-    if ( flags & JOY_BUTTON3 )
-        buttons |= wxJOY_BUTTON3;
-    if ( flags & JOY_BUTTON4 )
-        buttons |= wxJOY_BUTTON4;
-
-    // the event ids aren't consecutive so we can't use table based lookup
-    int joystick;
-    wxEventType eventType;
-    switch ( msg )
-    {
-        case MM_JOY1MOVE:
-            joystick = 1;
-            eventType = wxEVT_JOY_MOVE;
-            break;
-
-        case MM_JOY2MOVE:
-            joystick = 2;
-            eventType = wxEVT_JOY_MOVE;
-            break;
-
-        case MM_JOY1ZMOVE:
-            joystick = 1;
-            eventType = wxEVT_JOY_ZMOVE;
-            break;
-
-        case MM_JOY2ZMOVE:
-            joystick = 2;
-            eventType = wxEVT_JOY_ZMOVE;
-            break;
-
-        case MM_JOY1BUTTONDOWN:
-            joystick = 1;
-            eventType = wxEVT_JOY_BUTTON_DOWN;
-            break;
-
-        case MM_JOY2BUTTONDOWN:
-            joystick = 2;
-            eventType = wxEVT_JOY_BUTTON_DOWN;
-            break;
-
-        case MM_JOY1BUTTONUP:
-            joystick = 1;
-            eventType = wxEVT_JOY_BUTTON_UP;
-            break;
-
-        case MM_JOY2BUTTONUP:
-            joystick = 2;
-            eventType = wxEVT_JOY_BUTTON_UP;
-            break;
-
-        default:
-            wxFAIL_MSG(wxT("no such joystick event"));
-
-            return false;
-    }
-
-    wxJoystickEvent event(eventType, buttons, joystick, change);
-    if ( eventType == wxEVT_JOY_ZMOVE )
-        event.SetZPosition(x);
-    else
-        event.SetPosition(wxPoint(x, y));
-    event.SetEventObject(this);
-
-    return HandleWindowEvent(event);
-}
 
 // ---------------------------------------------------------------------------
 // scrolling