Merge branch 'msw-offset-fixes'

Fix handling client area offset in wxMSW for different DC classes.

See #24924.

docs/changes.txt

@@ -108,6 +108,11 @@ Changes in behaviour not resulting in compilation errors
   platforms with RTF support. If you need to save/load plain text even for the
   files with the .rtf extension, specify wxTEXT_TYPE_PLAIN explicitly.
 
+- wxClientDC and wxPaintDC now correctly offset their origin by wxFrame
+  toolbar, if any. This is consistent with the behaviour of the other ports
+  but may require removing any compensation for not doing this before that may
+  be present in the application code.
+
 
 Changes in behaviour which may result in build errors
 -----------------------------------------------------

src/msw/dcclient.cpp

@@ -188,9 +188,8 @@ void wxClientDCImpl::InitDC()
 {
     wxWindowDCImpl::InitDC();
 
-    // in wxUniv build we must manually do some DC adjustments usually
-    // performed by Windows for us
-#if defined(__WXUNIVERSAL__)
+    // Account for the origin of the client area which is non-zero only for
+    // TLWs with (left or top) toolbar: we shouldn't draw over the toolbar.
     wxPoint ptOrigin = m_window->GetClientAreaOrigin();
     if ( ptOrigin.x || ptOrigin.y )
     {
@@ -198,6 +197,9 @@ void wxClientDCImpl::InitDC()
         SetDeviceOrigin(ptOrigin.x, ptOrigin.y);
     }
 
+    // in wxUniv build we must manually do some DC adjustments usually
+    // performed by Windows for us
+#if defined(__WXUNIVERSAL__)
     // clip the DC to avoid overwriting the non client area
     wxSize size = m_window->GetClientSize();
     DoSetClippingRegion(0, 0, size.x, size.y);

src/msw/overlay.cpp

@@ -161,9 +161,15 @@ void wxOverlayImpl::Init(wxDC* dc, int , int , int , int )
     m_window = dc->GetWindow();
 
     // The rectangle must be in screen coordinates
-    m_rect = m_window->GetClientRect();
+    m_rect = m_window->GetClientSize();
     m_window->ClientToScreen(&m_rect.x, &m_rect.y);
 
+    // Because wxClientDC adjusts the origin of the device context to the
+    // origin of the client area of the window, we need to compensate for it
+    // here, to make sure that (0, 0) of the rectangle corresponds to the point
+    // (0, 0) of the window client area.
+    m_rect.Offset(-m_window->GetClientAreaOrigin());
+
     if ( IsUsingConstantOpacity() )
     {
         m_bitmap.CreateWithDIPSize(m_rect.GetSize(), m_window->GetDPIScaleFactor());