split wxRegion(wxBitmap) ctor into two ctors with clearer semantics

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@27606 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/os2/region.h

@@ -15,6 +15,7 @@
 #include "wx/list.h"
 #include "wx/gdiobj.h"
 #include "wx/gdicmn.h"
+#include "wx/bitmap.h"
 #include "wx/os2/private.h"
 
 class WXDLLEXPORT wxRect;
@@ -45,6 +46,15 @@ public:
             );
     wxRegion(const wxRect& rRect);
     wxRegion(WXHRGN hRegion, WXHDC hPS); // Hangs on to this region
+    wxRegion( const wxBitmap& bmp)
+    {
+        Union(bmp);
+    }
+    wxRegion( const wxBitmap& bmp,
+              const wxColour& transColour, int tolerance = 0)
+    {
+        Union(bmp, transColour, tolerance);
+    }
 
     wxRegion();
     ~wxRegion();
@@ -179,13 +189,13 @@ public:
     wxBitmap        ConvertToBitmap(void) const;
 
     // Use the non-transparent pixels of a wxBitmap for the region to combine
-    // with this region.  If the bitmap has a mask then it will be used,
-    // otherwise the colour to be treated as transparent may be specified,
+    // with this region.  First version takes transparency from bitmap's mask,
+    // second lets the user specify the colour to be treated as transparent
     // along with an optional tolerance value.
-    bool            Union( const wxBitmap& rBmp
-                          ,const wxColour& rTransColour = wxNullColour
-                          ,int   nTolerance = 0
-                         );
+    // NOTE: implemented in common/rgncmn.cpp
+    bool Union(const wxBitmap& bmp);
+    bool Union(const wxBitmap& bmp,
+               const wxColour& transColour, int tolerance = 0);
 
     //
     // Does the region contain the point pt?