Add GLFW_RAW_INPUT and glfwRawInputSupported

This adds runtime per-window control of whether accelerated or raw mouse
motion is provided when the cursor is disabled.

Fixes #1400.
Closes #1401.

README.md

@@ -182,6 +182,7 @@ information on what to include when reporting a bug.
 - Added `GLFW_OSMESA_CONTEXT_API` for creating OpenGL contexts with
   [OSMesa](https://www.mesa3d.org/osmesa.html) (#281)
 - Added `GenerateMappings.cmake` script for updating gamepad mappings
+- Added `GLFW_RAW_INPUT` input mode and `glfwRawInputSupported` function (#1401)
 - Made `glfwCreateWindowSurface` emit an error when the window has a context
   (#1194,#1205)
 - Deprecated window parameter of clipboard string functions
@@ -489,6 +490,7 @@ skills.
  - Santi Zupancic
  - Jonas Ådahl
  - Lasse Öörni
+ - Nathan Poirier
  - All the unmentioned and anonymous contributors in the GLFW community, for bug
    reports, patches, feedback, testing and encouragement
 

include/GLFW/glfw3.h

@@ -1002,6 +1002,7 @@ extern "C" {
 #define GLFW_STICKY_KEYS            0x00033002
 #define GLFW_STICKY_MOUSE_BUTTONS   0x00033003
 #define GLFW_LOCK_KEY_MODS          0x00033004
+#define GLFW_RAW_INPUT              0x00033005
 
 #define GLFW_CURSOR_NORMAL          0x00034001
 #define GLFW_CURSOR_HIDDEN          0x00034002
@@ -3812,11 +3813,12 @@ 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 or @ref GLFW_LOCK_KEY_MODS.
+ *  @ref GLFW_STICKY_MOUSE_BUTTONS, @ref GLFW_LOCK_KEY_MODS or
+ *  @ref GLFW_RAW_INPUT.
  *
  *  @param[in] window The window to query.
  *  @param[in] mode One of `GLFW_CURSOR`, `GLFW_STICKY_KEYS`,
- *  `GLFW_STICKY_MOUSE_BUTTONS` or `GLFW_LOCK_KEY_MODS`.
+ *  `GLFW_STICKY_MOUSE_BUTTONS`, `GLFW_LOCK_KEY_MODS` or `GLFW_RAW_INPUT`.
  *
  *  @errors Possible errors include @ref GLFW_NOT_INITIALIZED and @ref
  *  GLFW_INVALID_ENUM.
@@ -3835,7 +3837,8 @@ 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 or @ref GLFW_LOCK_KEY_MODS.
+ *  @ref GLFW_STICKY_MOUSE_BUTTONS, @ref GLFW_LOCK_KEY_MODS or
+ *  @ref GLFW_RAW_INPUT.
  *
  *  If the mode is `GLFW_CURSOR`, the value must be one of the following cursor
  *  modes:
@@ -3867,9 +3870,14 @@ GLFWAPI int glfwGetInputMode(GLFWwindow* window, int mode);
  *  GLFW_MOD_CAPS_LOCK bit set when the event was generated with Caps Lock on,
  *  and the @ref GLFW_MOD_NUM_LOCK bit when Num Lock was on.
  *
+ *  If the mode is `GLFW_RAW_INPUT`, the value must be either `GLFW_TRUE` to
+ *  enable the use of raw input, or `GLFW_FALSE` to disable it.  If enabled and
+ *  supported by the machine, the program will retrieve high-definition mouse
+ *  movement when cursor is grabbed.
+ *
  *  @param[in] window The window whose input mode to set.
  *  @param[in] mode One of `GLFW_CURSOR`, `GLFW_STICKY_KEYS`,
- *  `GLFW_STICKY_MOUSE_BUTTONS` or `GLFW_LOCK_KEY_MODS`.
+ *  `GLFW_STICKY_MOUSE_BUTTONS`, `GLFW_LOCK_KEY_MODS` or `GLFW_RAW_INPUT`.
  *  @param[in] value The new value of the specified input mode.
  *
  *  @errors Possible errors include @ref GLFW_NOT_INITIALIZED, @ref
@@ -3885,6 +3893,38 @@ GLFWAPI int glfwGetInputMode(GLFWwindow* window, int mode);
  */
 GLFWAPI void glfwSetInputMode(GLFWwindow* window, int mode, int value);
 
+/*! @brief Returns whether the raw input is supported.
+ *
+ * This function returns whether the raw input is supported by the current
+ * machine.
+ *
+ * Raw input allow to retrieve high-definition movement from mouse.
+ * Input from a high-definition mouse is much more precise than that from a
+ * standard mouse.  But often, they cannot be obtained through standard
+ * platforms API which transform mouse movement using their own improvements
+ * (like pointer acceleration).  Platform's improvements are ideal for pointer
+ * control but it is not so good for moving a first-person camera.  For this
+ * reason when the cursor of a window is grabbed by setting @ref GLFW_CURSOR
+ * to @ref GLFW_CURSOR_DISABLED, raw input is used.
+ *
+ * The use of raw input can be disabled using @ref glfwSetInputMode with
+ * @ref GLFW_RAW_INPUT mode.
+ *
+ *  @return `GLFW_TRUE` if high-definition mouse movement is supported, or
+ *  `GLFW_FALSE` otherwise.
+ *
+ *  @errors Possible errors include @ref GLFW_NOT_INITIALIZED.
+ *
+ *  @thread_safety This function may be called from any thread.
+ *
+ *  @sa @ref glfwSetInputMode
+ *
+ *  @since Added in version 3.3.
+ *
+ *  @ingroup input
+ */
+GLFWAPI int glfwRawInputSupported(void);
+
 /*! @brief Returns the layout-specific name of the specified printable key.
  *
  *  This function returns the name of the specified printable key, encoded as

src/cocoa_window.m

@@ -1297,6 +1297,16 @@ void _glfwPlatformSetWindowOpacity(_GLFWwindow* window, float opacity)
     [window->ns.object setAlphaValue:opacity];
 }
 
+void _glfwPlatformSetRawInput(_GLFWwindow *window, GLFWbool enabled)
+{
+    window->useRawInput = enabled;
+}
+
+GLFWbool _glfwPlatformRawInputSupported(void)
+{
+    return GLFW_FALSE;
+}
+
 void _glfwPlatformPollEvents(void)
 {
     for (;;)

src/input.c

@@ -484,6 +484,8 @@ GLFWAPI int glfwGetInputMode(GLFWwindow* handle, int mode)
             return window->stickyMouseButtons;
         case GLFW_LOCK_KEY_MODS:
             return window->lockKeyMods;
+        case GLFW_RAW_INPUT:
+            return window->useRawInput;
     }
 
     _glfwInputError(GLFW_INVALID_ENUM, "Invalid input mode 0x%08X", mode);
@@ -561,10 +563,18 @@ GLFWAPI void glfwSetInputMode(GLFWwindow* handle, int mode, int value)
     }
     else if (mode == GLFW_LOCK_KEY_MODS)
         window->lockKeyMods = value ? GLFW_TRUE : GLFW_FALSE;
+    else if (mode == GLFW_RAW_INPUT)
+        _glfwPlatformSetRawInput(window, value ? GLFW_TRUE : GLFW_FALSE);
     else
         _glfwInputError(GLFW_INVALID_ENUM, "Invalid input mode 0x%08X", mode);
 }
 
+GLFWAPI int glfwRawInputSupported(void)
+{
+    _GLFW_REQUIRE_INIT_OR_RETURN(0);
+    return _glfwPlatformRawInputSupported();
+}
+
 GLFWAPI const char* glfwGetKeyName(int key, int scancode)
 {
     _GLFW_REQUIRE_INIT_OR_RETURN(NULL);
@@ -1313,4 +1323,3 @@ GLFWAPI uint64_t glfwGetTimerFrequency(void)
     _GLFW_REQUIRE_INIT_OR_RETURN(0);
     return _glfwPlatformGetTimerFrequency();
 }
-

src/internal.h

@@ -390,6 +390,7 @@ struct _GLFWwindow
     char                keys[GLFW_KEY_LAST + 1];
     // Virtual cursor position when cursor is disabled
     double              virtualCursorPosX, virtualCursorPosY;
+    GLFWbool            useRawInput;
 
     _GLFWcontext        context;
 
@@ -596,6 +597,8 @@ const char* _glfwPlatformGetVersionString(void);
 void _glfwPlatformGetCursorPos(_GLFWwindow* window, double* xpos, double* ypos);
 void _glfwPlatformSetCursorPos(_GLFWwindow* window, double xpos, double ypos);
 void _glfwPlatformSetCursorMode(_GLFWwindow* window, int mode);
+void _glfwPlatformSetRawInput(_GLFWwindow *window, GLFWbool enabled);
+GLFWbool _glfwPlatformRawInputSupported(void);
 int _glfwPlatformCreateCursor(_GLFWcursor* cursor,
                               const GLFWimage* image, int xhot, int yhot);
 int _glfwPlatformCreateStandardCursor(_GLFWcursor* cursor, int shape);

src/null_window.c

@@ -196,6 +196,16 @@ void _glfwPlatformSetWindowOpacity(_GLFWwindow* window, float opacity)
 {
 }
 
+void _glfwPlatformSetRawInput(_GLFWwindow *window, GLFWbool enabled)
+{
+    window->useRawInput = enabled;
+}
+
+GLFWbool _glfwPlatformRawInputSupported(void)
+{
+    return GLFW_FALSE;
+}
+
 void _glfwPlatformShowWindow(_GLFWwindow* window)
 {
 }

src/win32_window.c

@@ -281,7 +281,7 @@ static void disableCursor(_GLFWwindow* window)
     _glfwCenterCursorInContentArea(window);
     updateClipRect(window);
 
-    if (!RegisterRawInputDevices(&rid, 1, sizeof(rid)))
+    if (window->useRawInput && !RegisterRawInputDevices(&rid, 1, sizeof(rid)))
     {
         _glfwInputErrorWin32(GLFW_PLATFORM_ERROR,
                              "Win32: Failed to register raw input device");
@@ -301,7 +301,7 @@ static void enableCursor(_GLFWwindow* window)
                               _glfw.win32.restoreCursorPosY);
     updateCursorImage(window);
 
-    if (!RegisterRawInputDevices(&rid, 1, sizeof(rid)))
+    if (window->useRawInput && !RegisterRawInputDevices(&rid, 1, sizeof(rid)))
     {
         _glfwInputErrorWin32(GLFW_PLATFORM_ERROR,
                              "Win32: Failed to remove raw input device");
@@ -816,9 +816,18 @@ static LRESULT CALLBACK windowProc(HWND hWnd, UINT uMsg,
 
             // Disabled cursor motion input is provided by WM_INPUT
             if (window->cursorMode == GLFW_CURSOR_DISABLED)
-                break;
+            {
+                if (_glfw.win32.disabledCursorWindow != window || window->useRawInput)
+                    break;
 
-            _glfwInputCursorPos(window, x, y);
+                const int dx = x - window->win32.lastCursorPosX;
+                const int dy = y - window->win32.lastCursorPosY;
+                _glfwInputCursorPos(window,
+                                    window->virtualCursorPosX + dx,
+                                    window->virtualCursorPosY + dy);
+            }
+            else
+                _glfwInputCursorPos(window, x, y);
 
             window->win32.lastCursorPosX = x;
             window->win32.lastCursorPosY = y;
@@ -847,7 +856,7 @@ static LRESULT CALLBACK windowProc(HWND hWnd, UINT uMsg,
             int dx, dy;
 
             // Only process input when disabled cursor mode is applied
-            if (_glfw.win32.disabledCursorWindow != window)
+            if (_glfw.win32.disabledCursorWindow != window || !window->useRawInput)
                 break;
 
             GetRawInputData(ri, RID_INPUT, NULL, &size, sizeof(RAWINPUTHEADER));
@@ -1845,6 +1854,24 @@ void _glfwPlatformSetWindowOpacity(_GLFWwindow* window, float opacity)
     }
 }
 
+void _glfwPlatformSetRawInput(_GLFWwindow *window, GLFWbool enabled)
+{
+    if (window->useRawInput != enabled)
+    {
+        int update = (_glfw.win32.disabledCursorWindow == window);
+        if (update)
+            enableCursor(window);
+        window->useRawInput = enabled;
+        if (update)
+            disableCursor(window);
+    }
+}
+
+GLFWbool _glfwPlatformRawInputSupported(void)
+{
+    return GLFW_TRUE;
+}
+
 void _glfwPlatformPollEvents(void)
 {
     MSG msg;

src/window.c

@@ -202,6 +202,7 @@ GLFWAPI GLFWwindow* glfwCreateWindow(int width, int height,
     window->floating    = wndconfig.floating;
     window->focusOnShow = wndconfig.focusOnShow;
     window->cursorMode  = GLFW_CURSOR_NORMAL;
+    window->useRawInput = GLFW_TRUE;
 
     window->minwidth    = GLFW_DONT_CARE;
     window->minheight   = GLFW_DONT_CARE;
@@ -1097,4 +1098,3 @@ GLFWAPI void glfwPostEmptyEvent(void)
     _GLFW_REQUIRE_INIT();
     _glfwPlatformPostEmptyEvent();
 }
-

src/wl_window.c

@@ -1318,6 +1318,16 @@ void _glfwPlatformSetWindowOpacity(_GLFWwindow* window, float opacity)
 {
 }
 
+void _glfwPlatformSetRawInput(_GLFWwindow *window, GLFWbool enabled)
+{
+    window->useRawInput = enabled;
+}
+
+GLFWbool _glfwPlatformRawInputSupported(void)
+{
+    return GLFW_FALSE;
+}
+
 void _glfwPlatformPollEvents(void)
 {
     handleEvents(0);

src/x11_window.c

@@ -526,7 +526,7 @@ static void updateCursorImage(_GLFWwindow* window)
 //
 static void disableCursor(_GLFWwindow* window)
 {
-    if (_glfw.x11.xi.available)
+    if (_glfw.x11.xi.available && window->useRawInput)
     {
         XIEventMask em;
         unsigned char mask[XIMaskLen(XI_RawMotion)] = { 0 };
@@ -557,7 +557,7 @@ static void disableCursor(_GLFWwindow* window)
 //
 static void enableCursor(_GLFWwindow* window)
 {
-    if (_glfw.x11.xi.available)
+    if (_glfw.x11.xi.available && window->useRawInput)
     {
         XIEventMask em;
         unsigned char mask[] = { 0 };
@@ -1183,6 +1183,7 @@ static void processEvent(XEvent *event)
             _GLFWwindow* window = _glfw.x11.disabledCursorWindow;
 
             if (window &&
+                window->useRawInput &&
                 event->xcookie.extension == _glfw.x11.xi.majorOpcode &&
                 XGetEventData(_glfw.x11.display, &event->xcookie) &&
                 event->xcookie.evtype == XI_RawMotion)
@@ -1483,7 +1484,7 @@ static void processEvent(XEvent *event)
                 {
                     if (_glfw.x11.disabledCursorWindow != window)
                         return;
-                    if (_glfw.x11.xi.available)
+                    if (_glfw.x11.xi.available && window->useRawInput)
                         return;
 
                     const int dx = x - window->x11.lastCursorPosX;
@@ -2652,6 +2653,24 @@ void _glfwPlatformSetWindowOpacity(_GLFWwindow* window, float opacity)
                     PropModeReplace, (unsigned char*) &value, 1);
 }
 
+void _glfwPlatformSetRawInput(_GLFWwindow *window, GLFWbool enabled)
+{
+    if (window->useRawInput != enabled)
+    {
+        int update = (_glfw.x11.disabledCursorWindow == window && _glfw.x11.xi.available);
+        if (update)
+            enableCursor(window);
+        window->useRawInput = enabled;
+        if (update)
+            disableCursor(window);
+    }
+}
+
+GLFWbool _glfwPlatformRawInputSupported(void)
+{
+    return _glfw.x11.xi.available;
+}
+
 void _glfwPlatformPollEvents(void)
 {
     _GLFWwindow* window;

tests/cursor.c

@@ -163,6 +163,19 @@ static void key_callback(GLFWwindow* window, int key, int scancode, int action,
             printf("(( cursor is hidden ))\n");
             break;
 
+        case GLFW_KEY_R:
+            if (glfwGetInputMode(window, GLFW_RAW_INPUT))
+            {
+                glfwSetInputMode(window, GLFW_RAW_INPUT, GLFW_FALSE);
+                printf("(( raw input is disabled ))\n");
+            }
+            else
+            {
+                glfwSetInputMode(window, GLFW_RAW_INPUT, GLFW_TRUE);
+                printf("(( raw input is enabled ))\n");
+            }
+            break;
+
         case GLFW_KEY_SPACE:
             swap_interval = 1 - swap_interval;
             printf("(( swap interval: %i ))\n", swap_interval);