Implement glfwGetJoystickHats

This moves the buttons-as-hats logic to shared code and adds the
GLFW_JOYSTICK_HAT_BUTTONS input mode as a way to disable this legacy
behavior.

Fixes #889.

README.md

@@ -127,11 +127,14 @@ information on what to include when reporting a bug.
 - Added `glfwSetWindowMaximizeCallback` and `GLFWwindowmaximizefun` for
   receiving window maximization events (#778)
 - Added `glfwSetWindowAttrib` function for changing window attributes (#537)
+- Added `glfwGetJoystickHats` function for querying joystick hats
+  (#889,#906,#934)
 - Added `glfwInitHint` function for setting library initialization hints
 - Added headless [OSMesa](http://mesa3d.org/osmesa.html) backend (#850)
 - Added definition of `GLAPIENTRY` to public header
 - Added `GLFW_CENTER_CURSOR` window hint for controlling cursor centering
   (#749,#842)
+- Added `GLFW_JOYSTICK_HAT_BUTTONS` init hint (#889)
 - Added macOS specific `GLFW_COCOA_RETINA_FRAMEBUFFER` window hint
 - Added macOS specific `GLFW_COCOA_FRAME_AUTOSAVE` window hint (#195)
 - Added macOS specific `GLFW_COCOA_GRAPHICS_SWITCHING` window hint (#377,#935)

docs/Doxyfile.in

@@ -204,7 +204,8 @@ ALIASES                = "thread_safety=@par Thread safety\n" \
                          "x11=__X11:__" \
                          "wayland=__Wayland:__" \
                          "win32=__Windows:__" \
-                         "macos=__macOS:__"
+                         "macos=__macOS:__" \
+                         "linux=__Linux:__"
 
 # This tag can be used to specify a number of word-keyword mappings (TCL only).
 # A mapping has the form "name=value". For example adding

docs/input.dox

@@ -510,21 +510,24 @@ A simple mouse wheel, being vertical, provides offsets along the Y-axis.
 
 The joystick functions expose connected joysticks and controllers, with both
 referred to as joysticks.  It supports up to sixteen joysticks, ranging from
-`GLFW_JOYSTICK_1`, `GLFW_JOYSTICK_2` up to `GLFW_JOYSTICK_LAST`.  You can test
+`GLFW_JOYSTICK_1`, `GLFW_JOYSTICK_2` up to and including `GLFW_JOYSTICK_16` or
-whether a [joystick](@ref joysticks) is present with @ref glfwJoystickPresent.
+`GLFW_JOYSTICK_LAST`.  You can test whether a [joystick](@ref joysticks) is
+present with @ref glfwJoystickPresent.
 
 @code
 int present = glfwJoystickPresent(GLFW_JOYSTICK_1);
 @endcode
 
 When GLFW is initialized, detected joysticks are added to to the beginning of
-the array, starting with `GLFW_JOYSTICK_1`.  Once a joystick is detected, it
+the array.  Once a joystick is detected, it keeps its assigned ID until it is
-keeps its assigned index until it is disconnected, so as joysticks are connected
+disconnected or the library is terminated, so as joysticks are connected and
-and disconnected, they will become spread out.
+disconnected, there may appear gaps in the IDs.
 
-Joystick state is updated as needed when a joystick function is called and does
+Joystick axis, button and hat state is updated when polled and does not require
-not require a window to be created or @ref glfwPollEvents or @ref glfwWaitEvents
+a window to be created or events to be processed.  However, if you want joystick
-to be called.
+connection and disconnection events reliably delivered to the
+[joystick callback](@ref joystick_event) then you must
+[process events](@ref events).
 
 To see all the properties of all connected joysticks in real-time, run the
 `joysticks` test program.
@@ -538,7 +541,7 @@ returned array.
 
 @code
 int count;
-const float* axes = glfwGetJoystickAxes(GLFW_JOYSTICK_1, &count);
+const float* axes = glfwGetJoystickAxes(GLFW_JOYSTICK_5, &count);
 @endcode
 
 Each element in the returned array is a value between -1.0 and 1.0.
@@ -552,11 +555,55 @@ returned array.
 
 @code
 int count;
-const unsigned char* axes = glfwGetJoystickButtons(GLFW_JOYSTICK_1, &count);
+const unsigned char* buttons = glfwGetJoystickButtons(GLFW_JOYSTICK_3, &count);
 @endcode
 
 Each element in the returned array is either `GLFW_PRESS` or `GLFW_RELEASE`.
 
+For backward compatibility with earlier versions that did not have @ref
+glfwGetJoystickHats, the button array by default also includes all hats.  See
+the reference documentation for @ref glfwGetJoystickButtons for details.
+
+
+@subsection joystick_hat Joystick hat states
+
+The states of all hats are returned by @ref glfwGetJoystickHats.  See the
+reference documentation for the lifetime of the returned array.
+
+@code
+int count;
+const unsigned char* hats = glfwGetJoystickHats(GLFW_JOYSTICK_7, &count);
+@endcode
+
+Each element in the returned array is one of the following:
+
+Name                  | Value
+--------------------- | --------------------------------
+`GLFW_HAT_CENTERED`   | 0
+`GLFW_HAT_UP`         | 1
+`GLFW_HAT_RIGHT`      | 2
+`GLFW_HAT_DOWN`       | 4
+`GLFW_HAT_LEFT`       | 8
+`GLFW_HAT_RIGHT_UP`   | `GLFW_HAT_RIGHT` \| `GLFW_HAT_UP`
+`GLFW_HAT_RIGHT_DOWN` | `GLFW_HAT_RIGHT` \| `GLFW_HAT_DOWN`
+`GLFW_HAT_LEFT_UP`    | `GLFW_HAT_LEFT` \| `GLFW_HAT_UP`
+`GLFW_HAT_LEFT_DOWN`  | `GLFW_HAT_LEFT` \| `GLFW_HAT_DOWN`
+
+The diagonal directions are bitwise combinations of the primary (up, right, down
+and left) directions and you can test for these individually by ANDing it with
+the corresponding direction.
+
+@code
+if (hats[2] & GLFW_HAT_RIGHT)
+{
+    // State of hat 2 could be right-up, right or right-down
+}
+@endcode
+
+For backward compatibility with earlier versions that did not have @ref
+glfwGetJoystickHats, all hats are by default also included in the button array.
+See the reference documentation for @ref glfwGetJoystickButtons for details.
+
 
 @subsection joystick_name Joystick name
 
@@ -565,7 +612,7 @@ glfwGetJoystickName.  See the reference documentation for the lifetime of the
 returned string.           
 
 @code
-const char* name = glfwGetJoystickName(GLFW_JOYSTICK_1);
+const char* name = glfwGetJoystickName(GLFW_JOYSTICK_4);
 @endcode
 
 Joystick names are not guaranteed to be unique.  Two joysticks of the same model

docs/intro.dox

@@ -77,6 +77,11 @@ platform but they will only affect their specific platform.  Other platforms
 will simply ignore them.  Setting these hints requires no platform specific
 headers or calls.
 
+@anchor GLFW_JOYSTICK_HAT_BUTTONS
+__GLFW_JOYSTICK_HAT_BUTTONS__ specifies whether to also expose joystick hats as
+buttons, for compatibility with earlier versions of GLFW that did not have @ref
+glfwGetJoystickHats.
+
 
 @subsubsection init_hints_osx macOS specific hints
 
@@ -95,6 +100,7 @@ initialized.
 
 Init hint                       | Default value | Supported values
 ------------------------------- | ------------- | ----------------
+@ref GLFW_JOYSTICK_HAT_BUTTONS  | `GLFW_TRUE`   | `GLFW_TRUE` or `GLFW_FALSE`
 @ref GLFW_COCOA_CHDIR_RESOURCES | `GLFW_TRUE`   | `GLFW_TRUE` or `GLFW_FALSE`
 @ref GLFW_COCOA_MENUBAR         | `GLFW_TRUE`   | `GLFW_TRUE` or `GLFW_FALSE`
 

docs/news.dox

@@ -25,6 +25,13 @@ GLFW now supports changing the [GLFW_DECORATED](@ref GLFW_DECORATED_attrib),
 windows with @ref glfwSetWindowAttrib.
 
 
+@subsection news_33_joyhats Support for joystick hats
+
+GLFW now supports querying the hats of a joystick with @ref glfwGetJoystickHats
+and controlling whether hats are also exposed as buttons with the @ref
+GLFW_JOYSTICK_HAT_BUTTONS init hint.
+
+
 @subsection news_33_inithint Support for initialization hints
 
 GLFW now supports setting library initialization hints with @ref glfwInitHint.

include/GLFW/glfw3.h

@@ -297,7 +297,7 @@ extern "C" {
 #define GLFW_REPEAT                 2
 /*! @} */
 
-/*! @defgroup hat_directions Joystick hat directions
+/*! @defgroup hat_state Joystick hat states
  *
  *  See [joystick hat input](@ref joystick_hat) for how these are used.
  *
@@ -945,6 +945,8 @@ extern "C" {
 
 /*! @addtogroup init
  *  @{ */
+#define GLFW_JOYSTICK_HAT_BUTTONS   0x00050001
+
 #define GLFW_COCOA_CHDIR_RESOURCES  0x00051001
 #define GLFW_COCOA_MENUBAR          0x00051002
 /*! @} */
@@ -4020,7 +4022,7 @@ GLFWAPI int glfwJoystickPresent(int jid);
  *  This function returns the values of all axes of the specified joystick.
  *  Each element in the array is a value between -1.0 and 1.0.
  *
- *  Querying a joystick slot with no device present is not an error, but will
+ *  Querying a joystick ID with no device present is not an error, but will
  *  cause this function to return `NULL`.  Call @ref glfwJoystickPresent to
  *  check device presence.
  *
@@ -4053,7 +4055,14 @@ GLFWAPI const float* glfwGetJoystickAxes(int jid, int* count);
  *  This function returns the state of all buttons of the specified joystick.
  *  Each element in the array is either `GLFW_PRESS` or `GLFW_RELEASE`.
  *
- *  Querying a joystick slot with no device present is not an error, but will
+ *  For backward compatibility with earlier versions that did not have @ref
+ *  glfwGetJoystickHats, the button array also includes all hats, each
+ *  represented as four buttons.  The hats are in the same order as returned by
+ *  __glfwGetJoystickHats__ and are in the order _up_, _right_, _down_ and
+ *  _left_.  To disable these extra buttons, set the @ref
+ *  GLFW_JOYSTICK_HAT_BUTTONS init hint before initialization.
+ *
+ *  Querying a joystick ID with no device present is not an error, but will
  *  cause this function to return `NULL`.  Call @ref glfwJoystickPresent to
  *  check device presence.
  *
@@ -4085,27 +4094,32 @@ GLFWAPI const unsigned char* glfwGetJoystickButtons(int jid, int* count);
 /*! @brief Returns the state of all hats of the specified joystick.
  *
  *  This function returns the state of all hats of the specified joystick.
- *  Each element in the array is one of the following:
+ *  Each element in the array is one of the following values:
- *
+ *
- *      GLFW_HAT_CENTERED
+ *  Name                  | Value
- *      GLFW_HAT_UP
+ *  --------------------- | --------------------------------
- *      GLFW_HAT_RIGHT
+ *  `GLFW_HAT_CENTERED`   | 0
- *      GLFW_HAT_DOWN
+ *  `GLFW_HAT_UP`         | 1
- *      GLFW_HAT_LEFT
+ *  `GLFW_HAT_RIGHT`      | 2
- *      GLFW_HAT_RIGHT_UP
+ *  `GLFW_HAT_DOWN`       | 4
- *      GLFW_HAT_RIGHT_DOWN
+ *  `GLFW_HAT_LEFT`       | 8
- *      GLFW_HAT_LEFT_UP
+ *  `GLFW_HAT_RIGHT_UP`   | `GLFW_HAT_RIGHT` \| `GLFW_HAT_UP`
- *      GLFW_HAT_LEFT_DOWN
+ *  `GLFW_HAT_RIGHT_DOWN` | `GLFW_HAT_RIGHT` \| `GLFW_HAT_DOWN`
- *
+ *  `GLFW_HAT_LEFT_UP`    | `GLFW_HAT_LEFT` \| `GLFW_HAT_UP`
- *  For masking purposes, the hat state may be ANDed with the following primary
+ *  `GLFW_HAT_LEFT_DOWN`  | `GLFW_HAT_LEFT` \| `GLFW_HAT_DOWN`
- *  directions:
+ *
- *
+ *  The diagonal directions are bitwise combinations of the primary (up, right,
- *      GLFW_HAT_UP
+ *  down and left) directions and you can test for these individually by ANDing
- *      GLFW_HAT_RIGHT
+ *  it with the corresponding direction.
- *      GLFW_HAT_DOWN
+ *
- *      GLFW_HAT_LEFT
+ *  @code
- *
+ *  if (hats[2] & GLFW_HAT_RIGHT)                                
- *  Querying a joystick slot with no device present is not an error, but will
+ *  {                                                            
+ *      // State of hat 2 could be right-up, right or right-down 
+ *  }                                                            
+ *  @endcode
+ *
+ *  Querying a joystick ID with no device present is not an error, but will
  *  cause this function to return `NULL`.  Call @ref glfwJoystickPresent to
  *  check device presence.
  *
@@ -4119,7 +4133,7 @@ GLFWAPI const unsigned char* glfwGetJoystickButtons(int jid, int* count);
  *  @errors Possible errors include @ref GLFW_NOT_INITIALIZED, @ref
  *  GLFW_INVALID_ENUM and @ref GLFW_PLATFORM_ERROR.
  *
- *  @remark @linux Linux does not currently support hats.
+ *  @bug @linux Joystick hats are currently unimplemented.
  *
  *  @pointer_lifetime The returned array is allocated and freed by GLFW.  You
  *  should not free it yourself.  It is valid until the specified joystick is
@@ -4142,7 +4156,7 @@ GLFWAPI const unsigned char* glfwGetJoystickHats(int jid, int* count);
  *  The returned string is allocated and freed by GLFW.  You should not free it
  *  yourself.
  *
- *  Querying a joystick slot with no device present is not an error, but will
+ *  Querying a joystick ID with no device present is not an error, but will
  *  cause this function to return `NULL`.  Call @ref glfwJoystickPresent to
  *  check device presence.
  *

src/cocoa_joystick.m

@@ -204,7 +204,8 @@ static void matchCallback(void* context,
 
     js = _glfwAllocJoystick(name,
                             CFArrayGetCount(axes),
-                            CFArrayGetCount(buttons) + CFArrayGetCount(hats) * 4);
+                            CFArrayGetCount(buttons),
+                            CFArrayGetCount(hats));
 
     js->ns.device  = device;
     js->ns.axes    = axes;
@@ -358,33 +359,38 @@ int _glfwPlatformPollJoystick(int jid, int mode)
     }
     else if (mode == _GLFW_POLL_BUTTONS)
     {
-        CFIndex i, bi = 0;
+        CFIndex i;
 
         for (i = 0;  i < CFArrayGetCount(js->ns.buttons);  i++)
         {
             _GLFWjoyelementNS* button = (_GLFWjoyelementNS*)
                 CFArrayGetValueAtIndex(js->ns.buttons, i);
             const char value = getElementValue(js, button) ? 1 : 0;
-            _glfwInputJoystickButton(jid, bi++, value);
+            _glfwInputJoystickButton(jid, i, value);
         }
 
         for (i = 0;  i < CFArrayGetCount(js->ns.hats);  i++)
         {
+            const int states[9] =
+            {
+                GLFW_HAT_UP,
+                GLFW_HAT_RIGHT_UP,
+                GLFW_HAT_RIGHT,
+                GLFW_HAT_RIGHT_DOWN,
+                GLFW_HAT_DOWN,
+                GLFW_HAT_LEFT_DOWN,
+                GLFW_HAT_LEFT,
+                GLFW_HAT_LEFT_UP,
+                GLFW_HAT_CENTERED
+            };
+
             _GLFWjoyelementNS* hat = (_GLFWjoyelementNS*)
                 CFArrayGetValueAtIndex(js->ns.hats, i);
-
+            long state = getElementValue(js, hat);
-            // Bit fields of button presses for each direction, including nil
-            const int directions[9] = { 1, 3, 2, 6, 4, 12, 8, 9, 0 };
-
-            long j, state = getElementValue(js, hat);
             if (state < 0 || state > 8)
                 state = 8;
 
-            for (j = 0;  j < 4;  j++)
+            _glfwInputJoystickHat(jid, i, states[state]);
-            {
-                const char value = directions[state] & (1 << j) ? 1 : 0;
-                _glfwInputJoystickButton(jid, bi++, value);
-            }
         }
     }
 

src/init.c

@@ -46,6 +46,7 @@ _GLFWlibrary _glfw = { GLFW_FALSE };
 static GLFWerrorfun _glfwErrorCallback;
 static _GLFWinitconfig _glfwInitHints =
 {
+    GLFW_TRUE, // hat buttons
     {
         GLFW_TRUE, // menubar
         GLFW_TRUE  // chdir
@@ -188,6 +189,9 @@ GLFWAPI void glfwInitHint(int hint, int value)
 {
     switch (hint)
     {
+        case GLFW_JOYSTICK_HAT_BUTTONS:
+            _glfwInitHints.hatButtons = value;
+            return;
         case GLFW_COCOA_CHDIR_RESOURCES:
             _glfwInitHints.ns.chdir = value;
             return;

src/input.c

@@ -140,6 +140,19 @@ void _glfwInputJoystickButton(int jid, int button, char value)
     _glfw.joysticks[jid].buttons[button] = value;
 }
 
+void _glfwInputJoystickHat(int jid, int hat, char value)
+{
+    _GLFWjoystick* js = _glfw.joysticks + jid;
+    const int base = js->buttonCount + hat * 4;
+
+    js->buttons[base + 0] = (value & 0x01) ? GLFW_PRESS : GLFW_RELEASE;
+    js->buttons[base + 1] = (value & 0x02) ? GLFW_PRESS : GLFW_RELEASE;
+    js->buttons[base + 2] = (value & 0x04) ? GLFW_PRESS : GLFW_RELEASE;
+    js->buttons[base + 3] = (value & 0x08) ? GLFW_PRESS : GLFW_RELEASE;
+
+    js->hats[hat] = value;
+}
+
 
 //////////////////////////////////////////////////////////////////////////
 //////                       GLFW internal API                      //////
@@ -152,7 +165,10 @@ GLFWbool _glfwIsPrintable(int key)
            key == GLFW_KEY_KP_EQUAL;
 }
 
-_GLFWjoystick* _glfwAllocJoystick(const char* name, int axisCount, int buttonCount)
+_GLFWjoystick* _glfwAllocJoystick(const char* name,
+                                  int axisCount,
+                                  int buttonCount,
+                                  int hatCount)
 {
     int jid;
     _GLFWjoystick* js;
@@ -170,9 +186,11 @@ _GLFWjoystick* _glfwAllocJoystick(const char* name, int axisCount, int buttonCou
     js->present     = GLFW_TRUE;
     js->name        = strdup(name);
     js->axes        = calloc(axisCount, sizeof(float));
-    js->buttons     = calloc(buttonCount, 1);
+    js->buttons     = calloc(buttonCount + hatCount * 4, 1);
+    js->hats        = calloc(hatCount, 1);
     js->axisCount   = axisCount;
     js->buttonCount = buttonCount;
+    js->hatCount    = hatCount;
 
     return js;
 }
@@ -182,6 +200,7 @@ void _glfwFreeJoystick(_GLFWjoystick* js)
     free(js->name);
     free(js->axes);
     free(js->buttons);
+    free(js->hats);
     memset(js, 0, sizeof(_GLFWjoystick));
 }
 
@@ -663,13 +682,23 @@ GLFWAPI const unsigned char* glfwGetJoystickButtons(int jid, int* count)
     if (!_glfwPlatformPollJoystick(jid, _GLFW_POLL_BUTTONS))
         return NULL;
 
+    if (_glfw.hints.init.hatButtons)
+    {
+        *count = _glfw.joysticks[jid].buttonCount +
+                 _glfw.joysticks[jid].hatCount * 4;
+    }
+    else
         *count = _glfw.joysticks[jid].buttonCount;
+
     return _glfw.joysticks[jid].buttons;
 }
 
 GLFWAPI const unsigned char* glfwGetJoystickHats(int jid, int* count)
 {
+    assert(jid >= GLFW_JOYSTICK_1);
+    assert(jid <= GLFW_JOYSTICK_LAST);
     assert(count != NULL);
+
     *count = 0;
 
     _GLFW_REQUIRE_INIT_OR_RETURN(NULL);
@@ -680,7 +709,14 @@ GLFWAPI const unsigned char* glfwGetJoystickHats(int jid, int* count)
         return NULL;
     }
 
+    if (!_glfw.joysticks[jid].present)
+        return NULL;
+
+    if (!_glfwPlatformPollJoystick(jid, _GLFW_POLL_BUTTONS))
         return NULL;
+
+    *count = _glfw.joysticks[jid].hatCount;
+    return _glfw.joysticks[jid].hats;
 }
 
 GLFWAPI const char* glfwGetJoystickName(int jid)

src/internal.h

@@ -266,6 +266,7 @@ typedef void (APIENTRY * PFN_vkVoidFunction)(void);
  */
 struct _GLFWinitconfig
 {
+    GLFWbool      hatButtons;
     struct {
         GLFWbool  menubar;
         GLFWbool  chdir;
@@ -476,6 +477,8 @@ struct _GLFWjoystick
     int             axisCount;
     unsigned char*  buttons;
     int             buttonCount;
+    unsigned char*  hats;
+    int             hatCount;
     char*           name;
 
     // This is defined in the joystick API's joystick.h
@@ -823,6 +826,13 @@ void _glfwInputJoystickAxis(int jid, int axis, float value);
  */
 void _glfwInputJoystickButton(int jid, int button, char value);
 
+/*! @brief Notifies shared code of the new value of a joystick hat.
+ *  @param[in] jid The joystick whose hat to update.
+ *  @param[in] button The index of the hat to update.
+ *  @param[in] value The new value of the hat.
+ */
+void _glfwInputJoystickHat(int jid, int hat, char value);
+
 
 //========================================================================
 // Utility functions
@@ -912,7 +922,7 @@ void _glfwFreeMonitor(_GLFWmonitor* monitor);
 /*! @brief Returns an available joystick object with arrays and name allocated.
  *  @ingroup utility
   */
-_GLFWjoystick* _glfwAllocJoystick(const char* name, int axisCount, int buttonCount);
+_GLFWjoystick* _glfwAllocJoystick(const char* name, int axisCount, int buttonCount, int hatCount);
 
 /*! @brief Frees arrays and name and flags the joystick object as unused.
  *  @ingroup utility

src/linux_joystick.c

@@ -77,7 +77,7 @@ static GLFWbool openJoystickDevice(const char* path)
     ioctl(fd, JSIOCGAXES, &axisCount);
     ioctl(fd, JSIOCGBUTTONS, &buttonCount);
 
-    js = _glfwAllocJoystick(name, axisCount, buttonCount);
+    js = _glfwAllocJoystick(name, axisCount, buttonCount, 0);
     if (!js)
     {
         close(fd);

src/win32_joystick.c

@@ -427,7 +427,8 @@ static BOOL CALLBACK deviceCallback(const DIDEVICEINSTANCE* di, void* user)
 
     js = _glfwAllocJoystick(name,
                             data.axisCount + data.sliderCount,
-                            data.buttonCount + data.povCount * 4);
+                            data.buttonCount,
+                            data.povCount);
     if (!js)
     {
         IDirectInputDevice8_Release(device);
@@ -512,7 +513,7 @@ void _glfwDetectJoystickConnectionWin32(void)
             if (XInputGetCapabilities(index, 0, &xic) != ERROR_SUCCESS)
                 continue;
 
-            js = _glfwAllocJoystick(getDeviceDescription(&xic), 6, 14);
+            js = _glfwAllocJoystick(getDeviceDescription(&xic), 6, 10, 1);
             if (!js)
                 continue;
 
@@ -561,7 +562,7 @@ int _glfwPlatformPollJoystick(int jid, int mode)
 
     if (js->win32.device)
     {
-        int i, j, ai = 0, bi = 0;
+        int i, ai = 0, bi = 0, pi = 0;
         HRESULT result;
         DIJOYSTATE state;
 
@@ -612,19 +613,26 @@ int _glfwPlatformPollJoystick(int jid, int mode)
 
                 case _GLFW_TYPE_POV:
                 {
-                    const int directions[9] = { 1, 3, 2, 6, 4, 12, 8, 9, 0 };
+                    const int states[9] =
+                    {
+                        GLFW_HAT_UP,
+                        GLFW_HAT_RIGHT_UP,
+                        GLFW_HAT_RIGHT,
+                        GLFW_HAT_RIGHT_DOWN,
+                        GLFW_HAT_DOWN,
+                        GLFW_HAT_LEFT_DOWN,
+                        GLFW_HAT_LEFT,
+                        GLFW_HAT_LEFT_UP,
+                        GLFW_HAT_CENTERED
+                    };
+
                     // Screams of horror are appropriate at this point
                     int state = LOWORD(*(DWORD*) data) / (45 * DI_DEGREES);
                     if (state < 0 || state > 8)
                         state = 8;
 
-                    for (j = 0;  j < 4;  j++)
+                    _glfwInputJoystickHat(jid, pi, states[state]);
-                    {
+                    pi++;
-                        const char value = (directions[state] & (1 << j)) != 0;
-                        _glfwInputJoystickButton(jid, bi, value);
-                        bi++;
-                    }
-
                     break;
                 }
             }
@@ -632,7 +640,7 @@ int _glfwPlatformPollJoystick(int jid, int mode)
     }
     else
     {
-        int i;
+        int i, dpad = 0;
         DWORD result;
         XINPUT_STATE xis;
         float axes[6] = { 0.f, 0.f, 0.f, 0.f, -1.f, -1.f };
@@ -647,11 +655,7 @@ int _glfwPlatformPollJoystick(int jid, int mode)
             XINPUT_GAMEPAD_BACK,
             XINPUT_GAMEPAD_START,
             XINPUT_GAMEPAD_LEFT_THUMB,
-            XINPUT_GAMEPAD_RIGHT_THUMB,
+            XINPUT_GAMEPAD_RIGHT_THUMB
-            XINPUT_GAMEPAD_DPAD_UP,
-            XINPUT_GAMEPAD_DPAD_RIGHT,
-            XINPUT_GAMEPAD_DPAD_DOWN,
-            XINPUT_GAMEPAD_DPAD_LEFT
         };
 
         result = XInputGetState(js->win32.index, &xis);
@@ -693,11 +697,22 @@ int _glfwPlatformPollJoystick(int jid, int mode)
         for (i = 0;  i < 6;  i++)
             _glfwInputJoystickAxis(jid, i, axes[i]);
 
-        for (i = 0;  i < 14;  i++)
+        for (i = 0;  i < 10;  i++)
         {
             const char value = (xis.Gamepad.wButtons & buttons[i]) ? 1 : 0;
             _glfwInputJoystickButton(jid, i, value);
         }
+
+        if (xis.Gamepad.wButtons & XINPUT_GAMEPAD_DPAD_UP)
+            dpad |= GLFW_HAT_UP;
+        if (xis.Gamepad.wButtons & XINPUT_GAMEPAD_DPAD_RIGHT)
+            dpad |= GLFW_HAT_RIGHT;
+        if (xis.Gamepad.wButtons & XINPUT_GAMEPAD_DPAD_DOWN)
+            dpad |= GLFW_HAT_DOWN;
+        if (xis.Gamepad.wButtons & XINPUT_GAMEPAD_DPAD_LEFT)
+            dpad |= GLFW_HAT_LEFT;
+
+        _glfwInputJoystickHat(jid, 0, dpad);
     }
 
     return GLFW_TRUE;

tests/joysticks.c

@@ -98,6 +98,7 @@ int main(void)
     memset(joysticks, 0, sizeof(joysticks));
 
     glfwSetErrorCallback(error_callback);
+    glfwInitHint(GLFW_JOYSTICK_HAT_BUTTONS, GLFW_FALSE);
 
     if (!glfwInit())
         exit(EXIT_FAILURE);
@@ -142,6 +143,8 @@ int main(void)
         {
             nk_layout_row_dynamic(nk, 30, 1);
 
+            nk_label(nk, "Hat buttons disabled", NK_TEXT_LEFT);
+
             if (joystick_count)
             {
                 for (i = 0;  i < joystick_count;  i++)
@@ -167,30 +170,78 @@ int main(void)
                          NK_WINDOW_MINIMIZABLE |
                          NK_WINDOW_TITLE))
             {
-                int j, axis_count, button_count;
+                int j, axis_count, button_count, hat_count;
                 const float* axes;
                 const unsigned char* buttons;
+                const unsigned char* hats;
 
                 nk_layout_row_dynamic(nk, 30, 1);
 
                 axes = glfwGetJoystickAxes(joysticks[i], &axis_count);
-                if (axis_count)
-                {
                 for (j = 0;  j < axis_count;  j++)
                     nk_slide_float(nk, -1.f, axes[j], 1.f, 0.1f);
-                }
 
                 nk_layout_row_dynamic(nk, 30, 8);
 
                 buttons = glfwGetJoystickButtons(joysticks[i], &button_count);
-                if (button_count)
-                {
                 for (j = 0;  j < button_count;  j++)
                 {
                     char name[16];
                     snprintf(name, sizeof(name), "%i", j + 1);
                     nk_select_label(nk, name, NK_TEXT_CENTERED, buttons[j]);
                 }
+
+                nk_layout_row_dynamic(nk, 30, 8);
+
+                hats = glfwGetJoystickHats(joysticks[i], &hat_count);
+                for (j = 0;  j < hat_count;  j++)
+                {
+                    float radius;
+                    struct nk_rect area;
+                    struct nk_vec2 center;
+
+                    if (nk_widget(&area, nk) != NK_WIDGET_VALID)
+                        continue;
+
+                    center = nk_vec2(area.x + area.w / 2.f,
+                                     area.y + area.h / 2.f);
+                    radius = NK_MIN(area.w, area.h) / 2.f;
+
+                    nk_stroke_circle(nk_window_get_canvas(nk),
+                                     nk_rect(center.x - radius,
+                                             center.y - radius,
+                                             radius * 2.f,
+                                             radius * 2.f),
+                                     1.f,
+                                     nk_rgb(175, 175, 175));
+
+                    if (hats[j])
+                    {
+                        const float angles[] =
+                        {
+                            0.f,           0.f,
+                            NK_PI * 1.5f,  NK_PI * 1.75f,
+                            NK_PI,         0.f,
+                            NK_PI * 1.25f, 0.f,
+                            NK_PI * 0.5f,  NK_PI * 0.25f,
+                            0.f,           0.f,
+                            NK_PI * 0.75f, 0.f,
+                        };
+                        const float cosa = nk_cos(angles[hats[j]]);
+                        const float sina = nk_sin(angles[hats[j]]);
+                        const struct nk_vec2 p0 = nk_vec2(0.f, -radius);
+                        const struct nk_vec2 p1 = nk_vec2( radius / 2.f, -radius / 3.f);
+                        const struct nk_vec2 p2 = nk_vec2(-radius / 2.f, -radius / 3.f);
+
+                        nk_fill_triangle(nk_window_get_canvas(nk),
+                                         center.x + cosa * p0.x + sina * p0.y,
+                                         center.y + cosa * p0.y - sina * p0.x,
+                                         center.x + cosa * p1.x + sina * p1.y,
+                                         center.y + cosa * p1.y - sina * p1.x,
+                                         center.x + cosa * p2.x + sina * p2.y,
+                                         center.y + cosa * p2.y - sina * p2.x,
+                                         nk_rgb(175, 175, 175));
+                    }
                 }
             }