Added glfwGetWindowFrameSize.

src/cocoa_window.m

@@ -1091,6 +1091,25 @@ void _glfwPlatformGetFramebufferSize(_GLFWwindow* window, int* width, int* heigh
         *height = (int) fbRect.size.height;
 }
 
+void _glfwPlatformGetWindowFrameSize(_GLFWwindow* window,
+                                     int* left, int* top,
+                                     int* right, int* bottom)
+{
+    const NSRect contentRect = [window->ns.view frame];
+    const NSRect frameRect = [window->ns.object frameRectForContentRect:contentRect];
+
+    if (left)
+        *left = contentRect.origin.x - frameRect.origin.x;
+    if (top)
+        *top = frameRect.origin.y + frameRect.size.height -
+               contentRect.origin.y - contentRect.size.height;
+    if (right)
+        *right = frameRect.origin.x + frameRect.size.width -
+                 contentRect.origin.x - contentRect.size.width;
+    if (bottom)
+        *bottom = contentRect.origin.y - frameRect.origin.y;
+}
+
 void _glfwPlatformIconifyWindow(_GLFWwindow* window)
 {
     if (window->monitor)

src/internal.h

@@ -524,6 +524,11 @@ void _glfwPlatformSetWindowSize(_GLFWwindow* window, int width, int height);
  */
 void _glfwPlatformGetFramebufferSize(_GLFWwindow* window, int* width, int* height);
 
+/*! @copydoc glfwGetWindowFrameSize
+ *  @ingroup platform
+ */
+void _glfwPlatformGetWindowFrameSize(_GLFWwindow* window, int* left, int* top, int* right, int* bottom);
+
 /*! @copydoc glfwIconifyWindow
  *  @ingroup platform
  */

src/win32_window.c

@@ -1120,6 +1120,28 @@ void _glfwPlatformGetFramebufferSize(_GLFWwindow* window, int* width, int* heigh
     _glfwPlatformGetWindowSize(window, width, height);
 }
 
+void _glfwPlatformGetWindowFrameSize(_GLFWwindow* window,
+                                     int* left, int* top,
+                                     int* right, int* bottom)
+{
+    RECT rect;
+    int width, height;
+
+    _glfwPlatformGetWindowSize(window, &width, &height);
+    SetRect(&rect, 0, 0, width, height);
+    AdjustWindowRectEx(&rect, window->win32.dwStyle,
+                       FALSE, window->win32.dwExStyle);
+
+    if (left)
+        *left = -rect.left;
+    if (top)
+        *top = -rect.top;
+    if (right)
+        *right = rect.right - width;
+    if (bottom)
+        *bottom = rect.bottom - height;
+}
+
 void _glfwPlatformIconifyWindow(_GLFWwindow* window)
 {
     ShowWindow(window->win32.handle, SW_MINIMIZE);

src/window.c

@@ -488,6 +488,15 @@ GLFWAPI void glfwGetFramebufferSize(GLFWwindow* handle, int* width, int* height)
     _glfwPlatformGetFramebufferSize(window, width, height);
 }
 
+GLFWAPI void glfwGetWindowFrameSize(GLFWwindow* handle,
+                                    int* left, int* top,
+                                    int* right, int* bottom)
+{
+    _GLFWwindow* window = (_GLFWwindow*) handle;
+    _GLFW_REQUIRE_INIT();
+    _glfwPlatformGetWindowFrameSize(window, left, top, right, bottom);
+}
+
 GLFWAPI void glfwIconifyWindow(GLFWwindow* handle)
 {
     _GLFWwindow* window = (_GLFWwindow*) handle;

src/x11_init.c

@@ -415,6 +415,8 @@ static void detectEWMH(void)
         getSupportedAtom(supportedAtoms, atomCount, "_NET_WM_PING");
     _glfw.x11.NET_ACTIVE_WINDOW =
         getSupportedAtom(supportedAtoms, atomCount, "_NET_ACTIVE_WINDOW");
+    _glfw.x11.NET_FRAME_EXTENTS =
+        getSupportedAtom(supportedAtoms, atomCount, "_NET_FRAME_EXTENTS");
     _glfw.x11.NET_WM_BYPASS_COMPOSITOR =
         getSupportedAtom(supportedAtoms, atomCount, "_NET_WM_BYPASS_COMPOSITOR");
 

src/x11_platform.h

@@ -120,6 +120,7 @@ typedef struct _GLFWlibraryX11
     Atom            NET_WM_STATE_FULLSCREEN;
     Atom            NET_WM_BYPASS_COMPOSITOR;
     Atom            NET_ACTIVE_WINDOW;
+    Atom            NET_FRAME_EXTENTS;
     Atom            MOTIF_WM_HINTS;
 
     // Xdnd (drag and drop) atoms

src/x11_window.c

@@ -1234,6 +1234,43 @@ void _glfwPlatformGetFramebufferSize(_GLFWwindow* window, int* width, int* heigh
     _glfwPlatformGetWindowSize(window, width, height);
 }
 
+void _glfwPlatformGetWindowFrameSize(_GLFWwindow* window,
+                                     int* left, int* top,
+                                     int* right, int* bottom)
+{
+    long* extents = NULL;
+
+    if (left)
+        *left = 0;
+    if (top)
+        *top = 0;
+    if (right)
+        *right = 0;
+    if (bottom)
+        *bottom = 0;
+
+    if (_glfw.x11.NET_FRAME_EXTENTS == None)
+        return;
+
+    if (_glfwGetWindowProperty(window->x11.handle,
+                               _glfw.x11.NET_FRAME_EXTENTS,
+                               XA_CARDINAL,
+                               (unsigned char**) &extents) == 4)
+    {
+        if (left)
+            *left = extents[0];
+        if (top)
+            *top = extents[2];
+        if (right)
+            *right = extents[1];
+        if (bottom)
+            *bottom = extents[3];
+    }
+
+    if (extents)
+        XFree(extents);
+}
+
 void _glfwPlatformIconifyWindow(_GLFWwindow* window)
 {
     if (window->x11.overrideRedirect)