Support Windows touch (Windows7 and later)

Thanks to: glfw#1736

include/GLFW/glfw3.h

@@ -320,18 +320,18 @@ extern "C" {
  */
 #define GLFW_FALSE                  0
 
-/*! @name Key and button actions
+/*! @name Key, button and touch actions
  *  @{ */
-/*! @brief The key or mouse button was released.
+/*! @brief The key or mouse button was released, or the touch ended.
  *
- *  The key or mouse button was released.
+ *  The key or mouse button was released, or the touch ended.
  *
  *  @ingroup input
  */
 #define GLFW_RELEASE                0
-/*! @brief The key or mouse button was pressed.
+/*! @brief The key or mouse button was pressed, or the touch started.
  *
- *  The key or mouse button was pressed.
+ *  The key or mouse button was pressed, or the touch started.
  *
  *  @ingroup input
  */
@@ -343,6 +343,13 @@ extern "C" {
  *  @ingroup input
  */
 #define GLFW_REPEAT                 2
+/*! @brief The touch was moved.
+ *
+ *  The touch was moved.
+ *
+ *  @ingroup input
+ */
+#define GLFW_MOVE                   3
 /*! @} */
 
 /*! @defgroup hat_state Joystick hat states
@@ -1149,6 +1156,7 @@ extern "C" {
 #define GLFW_LOCK_KEY_MODS          0x00033004
 #define GLFW_RAW_MOUSE_MOTION       0x00033005
 #define GLFW_IME                    0x00033006
+#define GLFW_TOUCH                  0x00033007
 
 #define GLFW_CURSOR_NORMAL          0x00034001
 #define GLFW_CURSOR_HIDDEN          0x00034002
@@ -2000,6 +2008,26 @@ typedef void (* GLFWpreeditcandidatefun)(GLFWwindow* window,
  */
 typedef void (* GLFWdropfun)(GLFWwindow* window, int path_count, const char* paths[]);
 
+/*! @brief The function pointer type for touch callbacks.
+ *
+ *  This is the function pointer type for touch callbacks.
+ *  A touch callback function has the following signature:
+ *  @code
+ *  void function_name(GLFWwindow* window, int touch, int action, double xpos, double ypos)
+ *  @endcode
+ *
+ *  @param[in] window The window that received the event.
+ *  @param[in] touch The touch that triggered the event.
+ *  @param[in] action One of @ref GLFW_PRESS, @ref GLFW_MOVE or @ref GLFW_RELEASE.
+ *  @param[in] xpos The new x-coordinate of the touch.
+ *  @param[in] ypos The new y-coordinate of the touch.
+ *
+ *  @sa @ref glfwSetTouchCallback
+ *
+ *  @ingroup input
+ */
+typedef void (* GLFWtouchfun)(GLFWwindow*,int,int,double,double);
+
 /*! @brief The function pointer type for monitor configuration callbacks.
  *
  *  This is the function pointer type for monitor configuration callbacks.
@@ -4625,12 +4653,12 @@ GLFWAPI void glfwPostEmptyEvent(void);
  *  This function returns the value of an input option for the specified window.
  *  The mode must be one of @ref GLFW_CURSOR, @ref GLFW_STICKY_KEYS,
  *  @ref GLFW_STICKY_MOUSE_BUTTONS, @ref GLFW_LOCK_KEY_MODS,
- *  @ref GLFW_RAW_MOUSE_MOTION or @ref GLFW_IME.
+ *  @ref GLFW_RAW_MOUSE_MOTION, @ref GLFW_IME or @ref GLFW_TOUCH.
  *
  *  @param[in] window The window to query.
  *  @param[in] mode One of `GLFW_CURSOR`, `GLFW_STICKY_KEYS`,
  *  `GLFW_STICKY_MOUSE_BUTTONS`, `GLFW_LOCK_KEY_MODS`, `GLFW_RAW_MOUSE_MOTION`,
- *  or `GLFW_IME`.
+ *  `GLFW_IME`, or `GLFW_TOUCH`..
  *
  *  @errors Possible errors include @ref GLFW_NOT_INITIALIZED and @ref
  *  GLFW_INVALID_ENUM.
@@ -4650,7 +4678,7 @@ GLFWAPI int glfwGetInputMode(GLFWwindow* window, int mode);
  *  This function sets an input mode option for the specified window.  The mode
  *  must be one of @ref GLFW_CURSOR, @ref GLFW_STICKY_KEYS,
  *  @ref GLFW_STICKY_MOUSE_BUTTONS, @ref GLFW_LOCK_KEY_MODS,
- *  @ref GLFW_RAW_MOUSE_MOTION or @ref GLFW_IME.
+ *  @ref GLFW_RAW_MOUSE_MOTION, @ref GLFW_IME or @ref GLFW_TOUCH.
  *
  *  If the mode is `GLFW_CURSOR`, the value must be one of the following cursor
  *  modes:
@@ -4693,10 +4721,15 @@ GLFWAPI int glfwGetInputMode(GLFWwindow* window, int mode);
  *  If the mode is `GLFW_IME`, the value must be either `GLFW_TRUE` to turn on
  *  IME, or `GLFW_FALSE` to turn off it.
  *
+ *  If the mode is `GLFW_TOUCH`, the value must be either `GLFW_TRUE` to enable 
+ *  touch input, or `GLFW_FALSE` to disable it. If touch input is not supported,
+ *  attempting to set this will emit @ref GLFW_FEATURE_UNAVAILABLE.  Call @ref
+ *  glfwTouchInputSupported to check for support.
+ *
  *  @param[in] window The window whose input mode to set.
  *  @param[in] mode One of `GLFW_CURSOR`, `GLFW_STICKY_KEYS`,
  *  `GLFW_STICKY_MOUSE_BUTTONS`, `GLFW_LOCK_KEY_MODS`,
- *  `GLFW_RAW_MOUSE_MOTION` or `GLFW_IME`.
+ *  `GLFW_RAW_MOUSE_MOTION`, `GLFW_IME` or `GLFW_TOUCH`.
  *  @param[in] value The new value of the specified input mode.
  *
  *  @errors Possible errors include @ref GLFW_NOT_INITIALIZED, @ref
@@ -4742,6 +4775,26 @@ GLFWAPI void glfwSetInputMode(GLFWwindow* window, int mode, int value);
  */
 GLFWAPI int glfwRawMouseMotionSupported(void);
 
+/*! @brief Returns whether touch input is supported.
+ *
+ *  This function returns whether touch input is supported on the current
+ *  system.  This status does not change after GLFW has been initialized so you
+ *  only need to check this once.  If you attempt to enable touch input on
+ *  a system that does not support it, @ref GLFW_PLATFORM_ERROR will be emitted.
+ *
+ *  @return `GLFW_TRUE` if touch input is supported on the current machine,
+ *  or `GLFW_FALSE` otherwise.
+ *
+ *  @errors Possible errors include @ref GLFW_NOT_INITIALIZED.
+ *
+ *  @thread_safety This function must only be called from the main thread.
+ *
+ *  @sa @ref glfwSetInputMode
+ *
+ *  @ingroup input
+ */
+GLFWAPI int glfwTouchInputSupported(void);
+
 /*! @brief Returns the layout-specific name of the specified printable key.
  *
  *  This function returns the name of the specified printable key, encoded as
@@ -5638,6 +5691,21 @@ GLFWAPI GLFWscrollfun glfwSetScrollCallback(GLFWwindow* window, GLFWscrollfun ca
  */
 GLFWAPI GLFWdropfun glfwSetDropCallback(GLFWwindow* window, GLFWdropfun callback);
 
+/*! @brief Sets the touch callback.
+ *
+ *  This function sets the touch callback, which is called when a touch is
+ *  started, ended or moved.
+ *
+ *  @param[in] window The window whose callback to set.
+ *  @param[in] callback The new touch callback, or `NULL` to remove the currently
+ *  set callback.
+ *  @return The previously set callback, or `NULL` if no callback was set or an
+ *  error occurred.
+ *
+ *  @ingroup input
+ */
+GLFWAPI GLFWtouchfun glfwSetTouchCallback(GLFWwindow* window, GLFWtouchfun callback);
+
 /*! @brief Returns whether the specified joystick is present.
  *
  *  This function returns whether the specified joystick is present.

src/cocoa_init.m

@@ -575,6 +575,8 @@ GLFWbool _glfwConnectCocoa(int platformID, _GLFWplatform* platform)
         _glfwResetPreeditTextCocoa,
         _glfwSetIMEStatusCocoa,
         _glfwGetIMEStatusCocoa,
+        _glfwSetTouchInputCocoa,
+        _glfwTouchInputSupportedCocoa,
         _glfwInitJoysticksCocoa,
         _glfwTerminateJoysticksCocoa,
         _glfwPollJoystickCocoa,

src/cocoa_platform.h

@@ -281,6 +281,9 @@ void _glfwSetWindowMousePassthroughCocoa(_GLFWwindow* window, GLFWbool enabled);
 void _glfwSetRawMouseMotionCocoa(_GLFWwindow *window, GLFWbool enabled);
 GLFWbool _glfwRawMouseMotionSupportedCocoa(void);
 
+void _glfwSetTouchInputCocoa(_GLFWwindow *window, GLFWbool enabled);
+GLFWbool _glfwTouchInputSupportedCocoa(void);
+
 void _glfwPollEventsCocoa(void);
 void _glfwWaitEventsCocoa(void);
 void _glfwWaitEventsTimeoutCocoa(double timeout);

src/cocoa_window.m

@@ -1635,6 +1635,17 @@ GLFWbool _glfwRawMouseMotionSupportedCocoa(void)
     return GLFW_FALSE;
 }
 
+void _glfwSetTouchInputCocoa(_GLFWwindow *window, GLFWbool enabled)
+{
+    _glfwInputError(GLFW_FEATURE_UNIMPLEMENTED,
+                    "Cocoa: Touch input not yet implemented");
+}
+
+GLFWbool _glfwTouchInputSupportedCocoa(void)
+{
+    return GLFW_FALSE;
+}
+
 void _glfwPollEventsCocoa(void)
 {
     @autoreleasepool {

src/input.c

@@ -37,7 +37,7 @@
 #include <string.h>
 
 // Internal key state used for sticky keys
-#define _GLFW_STICK 3
+#define _GLFW_STICK 4
 
 // Internal constants for gamepad mapping source types
 #define _GLFW_JOYSTICK_AXIS     1
@@ -455,6 +455,14 @@ void _glfwInputDrop(_GLFWwindow* window, int count, const char** paths)
         window->callbacks.drop((GLFWwindow*) window, count, paths);
 }
 
+// Notifies shared code of touch events
+//
+void _glfwInputTouch(_GLFWwindow* window, int touch, int action, double xpos, double ypos)
+{
+    if (window->callbacks.touch)
+        window->callbacks.touch((GLFWwindow*) window, touch, action, xpos, ypos);
+}
+
 // Notifies shared code of a joystick connection or disconnection
 //
 void _glfwInputJoystick(_GLFWjoystick* js, int event)
@@ -615,6 +623,8 @@ GLFWAPI int glfwGetInputMode(GLFWwindow* handle, int mode)
             return window->stickyKeys;
         case GLFW_STICKY_MOUSE_BUTTONS:
             return window->stickyMouseButtons;
+        case GLFW_TOUCH:
+            return window->touchInput;
         case GLFW_LOCK_KEY_MODS:
             return window->lockKeyMods;
         case GLFW_RAW_MOUSE_MOTION:
@@ -734,6 +744,24 @@ GLFWAPI void glfwSetInputMode(GLFWwindow* handle, int mode, int value)
             _glfw.platform.setIMEStatus(window, value ? GLFW_TRUE : GLFW_FALSE);
             return;
         }
+
+        case GLFW_TOUCH:
+        {
+            if (!_glfw.platform.touchInputSupported())
+            {
+                _glfwInputError(GLFW_PLATFORM_ERROR,
+                                "Touch input is not supported on this system");
+                return;
+            }
+
+            value = value ? GLFW_TRUE : GLFW_FALSE;
+            if (window->touchInput == value)
+                return;
+
+            window->touchInput = value;
+            _glfw.platform.setTouchInput(window, value);
+            return;
+        }
     }
 
     _glfwInputError(GLFW_INVALID_ENUM, "Invalid input mode 0x%08X", mode);
@@ -745,6 +773,12 @@ GLFWAPI int glfwRawMouseMotionSupported(void)
     return _glfw.platform.rawMouseMotionSupported();
 }
 
+GLFWAPI int glfwTouchInputSupported(void)
+{
+    _GLFW_REQUIRE_INIT_OR_RETURN(GLFW_FALSE);
+    return _glfw.platform.touchInputSupported();
+}
+
 GLFWAPI const char* glfwGetKeyName(int key, int scancode)
 {
     _GLFW_REQUIRE_INIT_OR_RETURN(NULL);
@@ -1582,6 +1616,14 @@ GLFWAPI int glfwGetGamepadState(int jid, GLFWgamepadstate* state)
     return GLFW_TRUE;
 }
 
+GLFWAPI GLFWtouchfun glfwSetTouchCallback(GLFWwindow* handle, GLFWtouchfun cbfun)
+{
+    _GLFWwindow* window = (_GLFWwindow*) handle;
+    _GLFW_REQUIRE_INIT_OR_RETURN(NULL);
+    _GLFW_SWAP(GLFWtouchfun, window->callbacks.touch, cbfun);
+    return cbfun;
+}
+
 GLFWAPI void glfwSetClipboardString(GLFWwindow* handle, const char* string)
 {
     assert(string != NULL);

src/internal.h

@@ -579,6 +579,7 @@ struct _GLFWwindow
 
     GLFWbool            stickyKeys;
     GLFWbool            stickyMouseButtons;
+    GLFWbool            touchInput;
     GLFWbool            lockKeyMods;
     int                 cursorMode;
     char                mouseButtons[GLFW_MOUSE_BUTTON_LAST + 1];
@@ -612,6 +613,7 @@ struct _GLFWwindow
         GLFWimestatusfun          imestatus;
         GLFWpreeditcandidatefun   preeditCandidate;
         GLFWdropfun               drop;
+        GLFWtouchfun              touch;
     } callbacks;
 
     // This is defined in platform.h
@@ -734,6 +736,8 @@ struct _GLFWplatform
     void (*resetPreeditText)(_GLFWwindow*);
     void (*setIMEStatus)(_GLFWwindow*,int);
     int  (*getIMEStatus)(_GLFWwindow*);
+    void (*setTouchInput)(_GLFWwindow*,int);
+    GLFWbool (*touchInputSupported)(void);
     GLFWbool (*initJoysticks)(void);
     void (*terminateJoysticks)(void);
     GLFWbool (*pollJoystick)(_GLFWjoystick*,int);
@@ -973,6 +977,8 @@ void _glfwInputScroll(_GLFWwindow* window, double xoffset, double yoffset);
 void _glfwInputMouseClick(_GLFWwindow* window, int button, int action, int mods);
 void _glfwInputCursorPos(_GLFWwindow* window, double xpos, double ypos);
 void _glfwInputCursorEnter(_GLFWwindow* window, GLFWbool entered);
+void _glfwInputTouch(_GLFWwindow* window, int touch, int action, double xpos, double ypos);
+
 void _glfwInputDrop(_GLFWwindow* window, int count, const char** names);
 void _glfwInputJoystick(_GLFWjoystick* js, int event);
 void _glfwInputJoystickAxis(_GLFWjoystick* js, int axis, float value);

src/null_init.c

@@ -60,6 +60,8 @@ GLFWbool _glfwConnectNull(int platformID, _GLFWplatform* platform)
         _glfwResetPreeditTextNull,
         _glfwSetIMEStatusNull,
         _glfwGetIMEStatusNull,
+        _glfwSetTouchInputNull,
+        _glfwTouchInputSupportedNull,
         _glfwInitJoysticksNull,
         _glfwTerminateJoysticksNull,
         _glfwPollJoystickNull,

src/null_platform.h

@@ -142,6 +142,9 @@ void _glfwResetPreeditTextNull(_GLFWwindow* window);
 void _glfwSetIMEStatusNull(_GLFWwindow* window, int active);
 int _glfwGetIMEStatusNull(_GLFWwindow* window);
 
+void _glfwSetTouchInputNull(_GLFWwindow *window, GLFWbool enabled);
+GLFWbool _glfwTouchInputSupportedNull(void);
+
 EGLenum _glfwGetEGLPlatformNull(EGLint** attribs);
 EGLNativeDisplayType _glfwGetEGLNativeDisplayNull(void);
 EGLNativeWindowType _glfwGetEGLNativeWindowNull(_GLFWwindow* window);

src/null_window.c

@@ -432,6 +432,15 @@ void _glfwShowWindowNull(_GLFWwindow* window)
     window->null.visible = GLFW_TRUE;
 }
 
+void _glfwSetTouchInputNull(_GLFWwindow *window, GLFWbool enabled)
+{
+}
+
+GLFWbool _glfwTouchInputSupportedNull(void)
+{
+    return GLFW_TRUE;
+}
+
 void _glfwRequestWindowAttentionNull(_GLFWwindow* window)
 {
 }

src/win32_init.c

@@ -113,6 +113,23 @@ static GLFWbool loadLibraries(void)
             _glfwPlatformGetModuleSymbol(_glfw.win32.dinput8.instance, "DirectInput8Create");
     }
 
+    _glfw.win32.user32.GetTouchInputInfo_ = (PFN_GetTouchInputInfo)
+        GetProcAddress(_glfw.win32.user32.instance, "GetTouchInputInfo");
+    _glfw.win32.user32.CloseTouchInputHandle_ = (PFN_CloseTouchInputHandle)
+        GetProcAddress(_glfw.win32.user32.instance, "CloseTouchInputHandle");
+    _glfw.win32.user32.RegisterTouchWindow_ = (PFN_RegisterTouchWindow)
+        GetProcAddress(_glfw.win32.user32.instance, "RegisterTouchWindow");
+    _glfw.win32.user32.UnregisterTouchWindow_ = (PFN_UnregisterTouchWindow)
+        GetProcAddress(_glfw.win32.user32.instance, "UnregisterTouchWindow");
+
+    if (_glfw.win32.user32.GetTouchInputInfo_ &&
+        _glfw.win32.user32.CloseTouchInputHandle_ &&
+        _glfw.win32.user32.RegisterTouchWindow_ &&
+        _glfw.win32.user32.UnregisterTouchWindow_)
+    {
+        _glfw.win32.touch.available = GLFW_TRUE;
+    }
+
     {
         int i;
         const char* names[] =
@@ -653,6 +670,8 @@ GLFWbool _glfwConnectWin32(int platformID, _GLFWplatform* platform)
         _glfwResetPreeditTextWin32,
         _glfwSetIMEStatusWin32,
         _glfwGetIMEStatusWin32,
+        _glfwSetTouchInputWin32,
+        _glfwTouchInputSupportedWin32,
         _glfwInitJoysticksWin32,
         _glfwTerminateJoysticksWin32,
         _glfwPollJoystickWin32,