Ticket #1570: win32-opengl-alpha.patch

xpra/platform/win32/common.py

@@ -257 +257 @@
 
 IID = GUID
 REFIID = POINTER(IID)
+
+
+HGRN = HANDLE
+class DWM_BLURBEHIND(Structure):
+    _fields_ = [
+        ("dwFlags",                 DWORD),
+        ("fEnable",                 BOOL),
+        ("hRgnBlur",                HGRN),
+        ("fTransitionOnMaximized",  BOOL),
+    ]
+CreateRectRgn = gdi32.CreateRectRgn
+CreateRectRgn.restype = HGRN
+CreateRectRgn.argtypes = [INT, INT, INT, INT]
+
+DWM_BB_ENABLE = 1
+DWM_BB_BLURREGION = 2
+DWM_BB_TRANSITIONONMAXIMIZED = 4
+
+dwmapi = WinDLL("dwmapi", use_last_error=True)
+DwmEnableBlurBehindWindow = dwmapi.DwmEnableBlurBehindWindow
+DwmEnableBlurBehindWindow.restype = HRESULT
+DwmEnableBlurBehindWindow.argtypes = [HWND, POINTER(DWM_BLURBEHIND)]

xpra/client/gl/gtk3/gl_client_window.py

@@ -9 +9 @@
 
 from xpra.client.gtk3.client_window import ClientWindow
 from xpra.client.gl.gtk_base.gl_client_window_common import GLClientWindowCommon
+from xpra.platform.win32.gui import get_window_handle
 
 
 class GLClientWindowBase(GLClientWindowCommon, ClientWindow):
@@ -17 +18 @@
         ClientWindow.set_alpha(self)
         rgb_formats = self._client_properties.get("encodings.rgb_formats", [])
         GLClientWindowCommon.add_rgb_formats(self, rgb_formats)
+        log.info("set_alpha() has_alpha=%s", self._has_alpha)
+        if self._has_alpha:
+            self.when_realized("alpha", self._enable_gl_alpha)
+            self.timeout_add(1000, self._enable_gl_alpha)
 
+    def _enable_gl_alpha(self):
+        log.info("_enable_gl_alpha() window=%s", self.get_window())
+        from xpra.platform.win32.common import CreateRectRgn, DWM_BLURBEHIND, DWM_BB_ENABLE, DWM_BB_BLURREGION, DwmEnableBlurBehindWindow
+        from ctypes import byref
+        rgn = CreateRectRgn(0, 0, 1000, 1000)
+        log.info("CreateRectRgn(..)=%#x", rgn)
+        bb = DWM_BLURBEHIND()
+        bb.dwFlags = DWM_BB_ENABLE | DWM_BB_BLURREGION
+        bb.hRgnBlur = rgn
+        bb.fEnable = True
+        hwnd = get_window_handle(self)
+        log.info("hwnd=%x", hwnd)
+        r = DwmEnableBlurBehindWindow(hwnd, byref(bb))
+        log.info("r=%s", r)
+
     def do_configure_event(self, event):
         log("GL do_configure_event(%s)", event)
         ClientWindow.do_configure_event(self, event)