Added window creation hint to disable native OS title-bar

- Disabling title-bar only implemented for win32 window.

include/GLFW/glfw3.h

@@ -842,6 +842,12 @@ extern "C" {
  *  [window attribute](@ref GLFW_FOCUS_ON_SHOW_attrib).
  */
 #define GLFW_FOCUS_ON_SHOW          0x0002000C
+ /*! @brief Window has titlebar window hint and attribute
+  *
+  *  Window has titlebar [window hint](@ref GLFW_TITLEBAR_hint) and
+  *  [window attribute](@ref GLFW_TITLEBAR_attrib).
+  */
+#define GLFW_TITLEBAR               0x0002000D
 
 /*! @brief Framebuffer bit depth hint.
  *
@@ -1291,8 +1297,30 @@ typedef void (* GLFWerrorfun)(int,const char*);
  *
  *  @ingroup window
  */
+
 typedef void (* GLFWwindowposfun)(GLFWwindow*,int,int);
 
+/*! @brief The function pointer type for window titlebar hittest callbacks.
+ *
+ *  This is the function pointer type for window titelebar hittest callbacks.
+ *  A window  titlebar hittest callback function has the following signature:
+ *  @code
+ *  void callback_name(GLFWwindow* window, int xpos, int ypos, int* hit)
+ *  @endcode
+ *
+ *  @param[in] window The window that was moved.
+ *  @param[in] xpos The x-coordinate of mouse, in screen coordinates.
+ *  @param[in] ypos The y-coordinate of mouse, in screen coordinates.
+ *  @param[out] hit 'true' or '1' if mouse hovering titlebar.
+ *
+ *  @sa @ref window_pos
+ *  @sa @ref glfwSetTitlebarHitTestCallback
+ *
+ *  @ingroup window
+ */
+typedef void (*GLFWtitlebarhittestfun)(GLFWwindow*, int, int, int*);
+
+
 /*! @brief The function pointer type for window size callbacks.
  *
  *  This is the function pointer type for window size callbacks.  A window size
@@ -3688,6 +3716,37 @@ GLFWAPI void* glfwGetWindowUserPointer(GLFWwindow* window);
  */
 GLFWAPI GLFWwindowposfun glfwSetWindowPosCallback(GLFWwindow* window, GLFWwindowposfun callback);
 
+/*! @brief Sets the titlebar hittest callback for the specified window.
+ *
+ *  This function sets the titlebar hittest callback of the specified window,
+ *  which is called when the mouse hoveres the window to ask client if it's
+ *  hovering over custom titlebar area which needs to be handles as a native
+ *  titlebar. The callback is provided with the x and y coordinates of the mouse
+ *  cursor in screen coordinates.
+ *
+ *  @param[in] window The window whose callback to set.
+ *  @param[in] callback The new callback, or `NULL` to remove the currently set
+ *  callback.
+ *  @return The previously set callback, or `NULL` if no callback was set or the
+ *  library had not been [initialized](@ref intro_init).
+ *
+ *  @callback_signature
+ *  @code
+ *  void function_name(GLFWwindow* window, int xpos, int ypos, int* hit)
+ *  @endcode
+ *  For more information about the callback parameters, see the
+ *  [function pointer type](@ref GLFWtitlebarhittestfun).
+ *
+ *  @errors Possible errors include @ref GLFW_NOT_INITIALIZED.
+ *
+ *  @thread_safety This function must only be called from the main thread.
+ *
+ *  @sa @ref window_pos
+ *
+ *  @ingroup window
+ */
+GLFWAPI GLFWtitlebarhittestfun glfwSetTitlebarHitTestCallback(GLFWwindow* window, GLFWtitlebarhittestfun callback);
+
 /*! @brief Sets the size callback for the specified window.
  *
  *  This function sets the size callback of the specified window, which is

premake5.lua

@@ -64,6 +64,11 @@ project "GLFW"
 			"_CRT_SECURE_NO_WARNINGS"
 		}
 
+		links
+		{
+			"Dwmapi.lib"
+		}
+
 	filter "configurations:Debug"
 		runtime "Debug"
 		symbols "on"

src/cocoa_window.m

@@ -1337,6 +1337,13 @@ void _glfwPlatformSetWindowDecorated(_GLFWwindow* window, GLFWbool enabled)
     } // autoreleasepool
 }
 
+void _glfwPlatformSetWindowTitlebar(_GLFWwindow* window, GLFWbool enabled)
+{
+    // TODO
+    _glfwInputError(GLFW_PLATFORM_ERROR,
+        "Cocoa: Window attribute setting not implemented yet");
+}
+
 void _glfwPlatformSetWindowFloating(_GLFWwindow* window, GLFWbool enabled)
 {
     @autoreleasepool {

src/internal.h

@@ -260,6 +260,7 @@ struct _GLFWwndconfig
     GLFWbool      resizable;
     GLFWbool      visible;
     GLFWbool      decorated;
+    GLFWbool      titlebar;
     GLFWbool      focused;
     GLFWbool      autoIconify;
     GLFWbool      floating;
@@ -373,6 +374,7 @@ struct _GLFWwindow
     // Window settings and state
     GLFWbool            resizable;
     GLFWbool            decorated;
+    GLFWbool            titlebar;
     GLFWbool            autoIconify;
     GLFWbool            floating;
     GLFWbool            focusOnShow;
@@ -400,6 +402,7 @@ struct _GLFWwindow
 
     struct {
         GLFWwindowposfun        pos;
+        GLFWtitlebarhittestfun  tbhittest;
         GLFWwindowsizefun       size;
         GLFWwindowclosefun      close;
         GLFWwindowrefreshfun    refresh;
@@ -673,6 +676,7 @@ int _glfwPlatformFramebufferTransparent(_GLFWwindow* window);
 float _glfwPlatformGetWindowOpacity(_GLFWwindow* window);
 void _glfwPlatformSetWindowResizable(_GLFWwindow* window, GLFWbool enabled);
 void _glfwPlatformSetWindowDecorated(_GLFWwindow* window, GLFWbool enabled);
+void _glfwPlatformSetWindowTitlebar(_GLFWwindow* window, GLFWbool enabled);
 void _glfwPlatformSetWindowFloating(_GLFWwindow* window, GLFWbool enabled);
 void _glfwPlatformSetWindowOpacity(_GLFWwindow* window, float opacity);
 
@@ -708,6 +712,7 @@ void _glfwPlatformUnlockMutex(_GLFWmutex* mutex);
 void _glfwInputWindowFocus(_GLFWwindow* window, GLFWbool focused);
 void _glfwInputWindowPos(_GLFWwindow* window, int xpos, int ypos);
 void _glfwInputWindowSize(_GLFWwindow* window, int width, int height);
+void _glfwInputTitleBarHitTest(_GLFWwindow* window, int posX, int posY, int* hit);
 void _glfwInputFramebufferSize(_GLFWwindow* window, int width, int height);
 void _glfwInputWindowContentScale(_GLFWwindow* window,
                                   float xscale, float yscale);

src/null_window.c

@@ -185,6 +185,10 @@ void _glfwPlatformSetWindowDecorated(_GLFWwindow* window, GLFWbool enabled)
 {
 }
 
+void _glfwPlatformSetWindowTitlebar(_GLFWwindow* window, GLFWbool enabled)
+{
+}
+
 void _glfwPlatformSetWindowFloating(_GLFWwindow* window, GLFWbool enabled)
 {
 }

src/win32_window.c

@@ -35,6 +35,7 @@
 #include <string.h>
 #include <windowsx.h>
 #include <shellapi.h>
+#include <uxtheme.h>
 
 // Returns the window style for the specified window
 //
@@ -508,6 +509,8 @@ static void releaseMonitor(_GLFWwindow* window)
 static LRESULT CALLBACK windowProc(HWND hWnd, UINT uMsg,
                                    WPARAM wParam, LPARAM lParam)
 {
+    static RECT border_thickness;
+
     _GLFWwindow* window = GetPropW(hWnd, L"GLFW");
     if (!window)
     {
@@ -545,6 +548,48 @@ static LRESULT CALLBACK windowProc(HWND hWnd, UINT uMsg,
 
                 break;
             }
+
+            case WM_CREATE:
+            {
+                if (_glfw.hints.window.titlebar)
+                    break;
+
+                //find border thickness
+                SetRectEmpty(&border_thickness);
+                if (GetWindowLongPtr(hWnd, GWL_STYLE) & WS_THICKFRAME)
+                {
+                    AdjustWindowRectEx(&border_thickness, GetWindowLongPtr(hWnd, GWL_STYLE) & ~WS_CAPTION, FALSE, NULL);
+                    border_thickness.left *= -1;
+                    border_thickness.top *= -1;
+                }
+                else// if (GetWindowLongPtr(hWnd, GWL_STYLE) & WS_BORDER)
+                {
+                    SetRect(&border_thickness, 4, 4, 4, 4);
+                }
+
+                MARGINS margins = { 0 };
+                DwmExtendFrameIntoClientArea(hWnd, &margins);
+                SetWindowPos(hWnd, NULL, 0, 0, 0, 0, SWP_SHOWWINDOW | SWP_NOMOVE | SWP_NOSIZE | SWP_FRAMECHANGED);
+
+                break;
+            }
+
+            case WM_ACTIVATE:
+            {
+                if (_glfw.hints.window.titlebar)
+                    break;
+
+                // Extend the frame into the client area.
+                MARGINS margins = { 0 };
+                auto hr = DwmExtendFrameIntoClientArea(hWnd, &margins);
+
+                if (!SUCCEEDED(hr))
+                {
+                    // Handle the error.
+                }
+
+                break;
+            }
         }
 
         return DefWindowProcW(hWnd, uMsg, wParam, lParam);
@@ -951,6 +996,16 @@ static LRESULT CALLBACK windowProc(HWND hWnd, UINT uMsg,
             break;
         }
 
+        case  WM_NCCALCSIZE:
+        {
+            if (window->titlebar)
+                break;
+
+            if (lParam)
+                return 0;
+
+            break;
+        }
         case WM_SIZE:
         {
             const GLFWbool iconified = wParam == SIZE_MINIMIZED;
@@ -1182,6 +1237,61 @@ static LRESULT CALLBACK windowProc(HWND hWnd, UINT uMsg,
             DragFinish(drop);
             return 0;
         }
+
+        case WM_ACTIVATE:
+        {
+            if (window->titlebar)
+                break;
+
+            // Extend the frame into the client area.
+            MARGINS margins = { 0 };
+            auto hr = DwmExtendFrameIntoClientArea(hWnd, &margins);
+
+            if (!SUCCEEDED(hr))
+            {
+                // Handle the error.
+            }
+
+            break;
+        }
+        case WM_NCHITTEST:
+        {
+            if (window->titlebar)
+                break;
+
+            POINT pt = { GET_X_LPARAM(lParam), GET_Y_LPARAM(lParam) };
+            ScreenToClient(hWnd, &pt);
+            RECT rc;
+            GetClientRect(hWnd, &rc);
+
+            int titlebarHittest = 0;
+            _glfwInputTitleBarHitTest(window, pt.x, pt.y, &titlebarHittest);
+
+            if (titlebarHittest)
+            {
+                return HTCAPTION;
+            }
+            else
+            {
+                enum { left = 1, top = 2, right = 4, bottom = 8 };
+                int hit = 0;
+                if (pt.x < border_thickness.left)               hit |= left;
+                if (pt.x > rc.right - border_thickness.right)   hit |= right;
+                if (pt.y < border_thickness.top)                hit |= top;
+                if (pt.y > rc.bottom - border_thickness.bottom) hit |= bottom;
+
+                if (hit & top && hit & left)        return HTTOPLEFT;
+                if (hit & top && hit & right)       return HTTOPRIGHT;
+                if (hit & bottom && hit & left)     return HTBOTTOMLEFT;
+                if (hit & bottom && hit & right)    return HTBOTTOMRIGHT;
+                if (hit & left)                     return HTLEFT;
+                if (hit & top)                      return HTTOP;
+                if (hit & right)                    return HTRIGHT;
+                if (hit & bottom)                   return HTBOTTOM;
+
+                return HTCLIENT;
+            }
+        }
     }
 
     return DefWindowProcW(hWnd, uMsg, wParam, lParam);
@@ -1828,6 +1938,11 @@ void _glfwPlatformSetWindowDecorated(_GLFWwindow* window, GLFWbool enabled)
     updateWindowStyles(window);
 }
 
+void _glfwPlatformSetWindowTitlebar(_GLFWwindow* window, GLFWbool enabled)
+{
+    updateWindowStyles(window);
+}
+
 void _glfwPlatformSetWindowFloating(_GLFWwindow* window, GLFWbool enabled)
 {
     const HWND after = enabled ? HWND_TOPMOST : HWND_NOTOPMOST;

src/window.c

@@ -86,6 +86,14 @@ void _glfwInputWindowSize(_GLFWwindow* window, int width, int height)
         window->callbacks.size((GLFWwindow*) window, width, height);
 }
 
+// Notifies shared code that mouse hittest needs to be resolved
+//
+void _glfwInputTitleBarHitTest(_GLFWwindow* window, int posX, int posY, int* hit)
+{
+    if (window->callbacks.tbhittest)
+        window->callbacks.tbhittest((GLFWwindow*)window, posX, posY, hit);
+}
+
 // Notifies shared code that a window has been iconified or restored
 //
 void _glfwInputWindowIconify(_GLFWwindow* window, GLFWbool iconified)
@@ -200,6 +208,7 @@ GLFWAPI GLFWwindow* glfwCreateWindow(int width, int height,
     window->monitor     = (_GLFWmonitor*) monitor;
     window->resizable   = wndconfig.resizable;
     window->decorated   = wndconfig.decorated;
+    window->titlebar    = wndconfig.titlebar;
     window->autoIconify = wndconfig.autoIconify;
     window->floating    = wndconfig.floating;
     window->focusOnShow = wndconfig.focusOnShow;
@@ -262,6 +271,7 @@ void glfwDefaultWindowHints(void)
     _glfw.hints.window.resizable    = GLFW_TRUE;
     _glfw.hints.window.visible      = GLFW_TRUE;
     _glfw.hints.window.decorated    = GLFW_TRUE;
+    _glfw.hints.window.titlebar     = GLFW_TRUE;
     _glfw.hints.window.focused      = GLFW_TRUE;
     _glfw.hints.window.autoIconify  = GLFW_TRUE;
     _glfw.hints.window.centerCursor = GLFW_TRUE;
@@ -345,6 +355,9 @@ GLFWAPI void glfwWindowHint(int hint, int value)
         case GLFW_DECORATED:
             _glfw.hints.window.decorated = value ? GLFW_TRUE : GLFW_FALSE;
             return;
+        case GLFW_TITLEBAR:
+            _glfw.hints.window.titlebar = value ? GLFW_TRUE : GLFW_FALSE;
+            return;
         case GLFW_FOCUSED:
             _glfw.hints.window.focused = value ? GLFW_TRUE : GLFW_FALSE;
             return;
@@ -828,6 +841,8 @@ GLFWAPI int glfwGetWindowAttrib(GLFWwindow* handle, int attrib)
             return window->resizable;
         case GLFW_DECORATED:
             return window->decorated;
+        case GLFW_TITLEBAR:
+            return window->titlebar;
         case GLFW_FLOATING:
             return window->floating;
         case GLFW_AUTO_ICONIFY:
@@ -889,6 +904,15 @@ GLFWAPI void glfwSetWindowAttrib(GLFWwindow* handle, int attrib, int value)
         if (!window->monitor)
             _glfwPlatformSetWindowDecorated(window, value);
     }
+    else if (attrib == GLFW_TITLEBAR)
+    {
+        if (window->titlebar == value)
+            return;
+
+        window->titlebar = value;
+        if (!window->monitor)
+            _glfwPlatformSetWindowTitlebar(window, value);
+    }
     else if (attrib == GLFW_FLOATING)
     {
         if (window->floating == value)
@@ -981,6 +1005,16 @@ GLFWAPI GLFWwindowposfun glfwSetWindowPosCallback(GLFWwindow* handle,
     return cbfun;
 }
 
+GLFWAPI GLFWtitlebarhittestfun glfwSetTitlebarHitTestCallback(GLFWwindow* handle, GLFWtitlebarhittestfun tbhtfun)
+{
+    _GLFWwindow* window = (_GLFWwindow*)handle;
+    assert(window != NULL);
+
+    _GLFW_REQUIRE_INIT_OR_RETURN(NULL);
+    _GLFW_SWAP_POINTERS(window->callbacks.tbhittest, tbhtfun);
+    return tbhtfun;
+}
+
 GLFWAPI GLFWwindowsizefun glfwSetWindowSizeCallback(GLFWwindow* handle,
                                                     GLFWwindowsizefun cbfun)
 {

src/wl_window.c

@@ -1111,6 +1111,13 @@ void _glfwPlatformSetWindowDecorated(_GLFWwindow* window, GLFWbool enabled)
     }
 }
 
+void _glfwPlatformSetWindowTitlebar(_GLFWwindow* window, GLFWbool enabled)
+{
+    // TODO
+    _glfwInputError(GLFW_PLATFORM_ERROR,
+        "Wayland: Window attribute setting not implemented yet");
+}
+
 void _glfwPlatformSetWindowFloating(_GLFWwindow* window, GLFWbool enabled)
 {
     // TODO

src/x11_window.c

@@ -2658,6 +2658,13 @@ void _glfwPlatformSetWindowDecorated(_GLFWwindow* window, GLFWbool enabled)
                     sizeof(hints) / sizeof(long));
 }
 
+void _glfwPlatformSetWindowTitlebar(_GLFWwindow* window, GLFWbool enabled)
+{
+    // TODO
+    _glfwInputError(GLFW_PLATFORM_ERROR,
+        "X11: Window attribute setting not implemented yet");
+}
+
 void _glfwPlatformSetWindowFloating(_GLFWwindow* window, GLFWbool enabled)
 {
     if (!_glfw.x11.NET_WM_STATE || !_glfw.x11.NET_WM_STATE_ABOVE)