Merge df8a36baeb into 4884232360

README.md

@@ -122,6 +122,7 @@ information on what to include when reporting a bug.
 
 ## Changelog
 
+- Added `glfwDragWindow` function for starting a drag operation on a window
 - Added `glfwGetKeyScancode` function that allows retrieving platform dependent
   scancodes for keys (#830)
 - Added `glfwSetWindowMaximizeCallback` and `GLFWwindowmaximizefun` for

examples/simple.c

@@ -68,6 +68,12 @@ static void error_callback(int error, const char* description)
     fprintf(stderr, "Error: %s\n", description);
 }
 
+void mouse_button_callback(GLFWwindow* window, int button, int action, int mods)
+{
+    if (button == GLFW_MOUSE_BUTTON_LEFT && action == GLFW_PRESS)
+        glfwDragWindow(window);
+}
+
 static void key_callback(GLFWwindow* window, int key, int scancode, int action, int mods)
 {
     if (key == GLFW_KEY_ESCAPE && action == GLFW_PRESS)
@@ -96,6 +102,7 @@ int main(void)
     }
 
     glfwSetKeyCallback(window, key_callback);
+    glfwSetMouseButtonCallback(window, mouse_button_callback);
 
     glfwMakeContextCurrent(window);
     gladLoadGLLoader((GLADloadproc) glfwGetProcAddress);

include/GLFW/glfw3.h

@@ -2751,6 +2751,25 @@ GLFWAPI void glfwHideWindow(GLFWwindow* window);
  */
 GLFWAPI void glfwFocusWindow(GLFWwindow* window);
 
+/*! @brief Starts drag operation to the specified window.
+ *
+ *  This function starts the drag operation of the specified window.
+ *
+ *  @param[in] window The window to start the dragging operation.
+ *
+ *  @errors Possible errors include @ref GLFW_NOT_INITIALIZED and @ref
+ *  GLFW_PLATFORM_ERROR.
+ *
+ *  @thread_safety This function must only be called from the main thread.
+ *
+ *  @sa @ref window_drag
+ *
+ *  @since Added in version 3.2.
+ *
+ *  @ingroup window
+ */
+GLFWAPI void glfwDragWindow(GLFWwindow* handle);
+
 /*! @brief Returns the monitor that the window uses for full screen mode.
  *
  *  This function returns the handle of the monitor that the specified window is

src/cocoa_window.m

@@ -1288,6 +1288,10 @@ void _glfwPlatformFocusWindow(_GLFWwindow* window)
     [window->ns.object makeKeyAndOrderFront:nil];
 }
 
+void _glfwPlatformDragWindow(_GLFWwindow* window)
+{
+}
+
 void _glfwPlatformSetWindowMonitor(_GLFWwindow* window,
                                    _GLFWmonitor* monitor,
                                    int xpos, int ypos,

src/internal.h

@@ -631,6 +631,7 @@ void _glfwPlatformMaximizeWindow(_GLFWwindow* window);
 void _glfwPlatformShowWindow(_GLFWwindow* window);
 void _glfwPlatformHideWindow(_GLFWwindow* window);
 void _glfwPlatformFocusWindow(_GLFWwindow* window);
+void _glfwPlatformDragWindow(_GLFWwindow* window);
 void _glfwPlatformSetWindowMonitor(_GLFWwindow* window, _GLFWmonitor* monitor, int xpos, int ypos, int width, int height, int refreshRate);
 int _glfwPlatformWindowFocused(_GLFWwindow* window);
 int _glfwPlatformWindowIconified(_GLFWwindow* window);

src/mir_window.c

@@ -576,6 +576,10 @@ void _glfwPlatformFocusWindow(_GLFWwindow* window)
                     "Mir: Unsupported function %s", __PRETTY_FUNCTION__);
 }
 
+void _glfwPlatformDragWindow(_GLFWwindow* window)
+{
+}
+
 void _glfwPlatformSetWindowMonitor(_GLFWwindow* window,
                                    _GLFWmonitor* monitor,
                                    int xpos, int ypos,

src/null_window.c

@@ -184,6 +184,10 @@ void _glfwPlatformFocusWindow(_GLFWwindow* window)
 {
 }
 
+void _glfwPlatformDragWindow(_GLFWwindow* window)
+{
+}
+
 int _glfwPlatformWindowFocused(_GLFWwindow* window)
 {
     return GLFW_FALSE;

src/win32_window.c

@@ -1323,6 +1323,12 @@ void _glfwPlatformFocusWindow(_GLFWwindow* window)
     SetFocus(window->win32.handle);
 }
 
+void _glfwPlatformDragWindow(_GLFWwindow* window)
+{
+    ReleaseCapture();
+    SendMessage(window->win32.handle, WM_NCLBUTTONDOWN, HTCAPTION, 0);
+}
+
 void _glfwPlatformSetWindowMonitor(_GLFWwindow* window,
                                    _GLFWmonitor* monitor,
                                    int xpos, int ypos,

src/window.c

@@ -698,6 +698,16 @@ GLFWAPI void glfwFocusWindow(GLFWwindow* handle)
     _glfwPlatformFocusWindow(window);
 }
 
+GLFWAPI void glfwDragWindow(GLFWwindow* handle)
+{
+    _GLFWwindow* window = (_GLFWwindow*) handle;
+    assert(window != NULL);
+
+    _GLFW_REQUIRE_INIT();
+
+    _glfwPlatformDragWindow(window);
+}
+
 GLFWAPI int glfwGetWindowAttrib(GLFWwindow* handle, int attrib)
 {
     _GLFWwindow* window = (_GLFWwindow*) handle;

src/wl_window.c

@@ -605,6 +605,11 @@ void _glfwPlatformFocusWindow(_GLFWwindow* window)
                     "Wayland: Focusing a window requires user interaction");
 }
 
+void _glfwPlatformDragWindow(_GLFWwindow* window)
+{
+    wl_shell_surface_move(window->wl.shellSurface, _glfw.wl.seat, _glfw.wl.pointerSerial);
+}
+
 void _glfwPlatformSetWindowMonitor(_GLFWwindow* window,
                                    _GLFWmonitor* monitor,
                                    int xpos, int ypos,

src/x11_window.c

@@ -43,6 +43,7 @@
 #define _NET_WM_STATE_REMOVE        0
 #define _NET_WM_STATE_ADD           1
 #define _NET_WM_STATE_TOGGLE        2
+#define _NET_WM_MOVERESIZE_MOVE     8
 
 // Additional mouse button names for XButtonEvent
 #define Button6            6
@@ -2091,6 +2092,28 @@ void _glfwPlatformFocusWindow(_GLFWwindow* window)
     XFlush(_glfw.x11.display);
 }
 
+void _glfwPlatformDragWindow(_GLFWwindow* window)
+{
+    int winXpos, winYpos;
+    double curXpos, curYpos;
+    XClientMessageEvent xclient;
+    memset(&xclient, 0, sizeof(XClientMessageEvent));
+    XUngrabPointer(_glfw.x11.display, 0);
+    XFlush(_glfw.x11.display);
+    _glfwPlatformGetCursorPos(window, &curXpos, &curYpos);
+    _glfwPlatformGetWindowPos(window, &winXpos, &winYpos);
+    xclient.type = ClientMessage;
+    xclient.window = window->x11.handle;
+    xclient.message_type = XInternAtom(_glfw.x11.display, "_NET_WM_MOVERESIZE", False);
+    xclient.format = 32;
+    xclient.data.l[0] = winXpos + curXpos;
+    xclient.data.l[1] = winYpos + curYpos;
+    xclient.data.l[2] = _NET_WM_MOVERESIZE_MOVE;
+    xclient.data.l[3] = 0;
+    xclient.data.l[4] = 0;
+    XSendEvent(_glfw.x11.display, _glfw.x11.root, False, SubstructureRedirectMask | SubstructureNotifyMask, (XEvent *)&xclient);
+}
+
 void _glfwPlatformSetWindowMonitor(_GLFWwindow* window,
                                    _GLFWmonitor* monitor,
                                    int xpos, int ypos,