moved HasTransparentBackground() from wxUniv to common wxWindow

[wxWidgets.git] / src / msw / dc.cpp

diff --git a/src/msw/dc.cpp b/src/msw/dc.cpp
index 5a3bbdd0cbd52309c3a4e94160bc85c5f8a2cc81..0ec26a8b0e9737fbd964f7e66d8476faea68a190 100644 (file)
--- a/src/msw/dc.cpp
+++ b/src/msw/dc.cpp
@@ -54,7 +54,6 @@
 #endif
 
 #include <string.h>
-#include <math.h>
 
 #if wxUSE_COMMON_DIALOGS && !defined(__WXMICROWIN__)
     #include <commdlg.h>
@@ -94,11 +93,6 @@ static const int VIEWPORT_EXTENT = 1000;
 static const int MM_POINTS = 9;
 static const int MM_METRIC = 10;
 
-// usually this is defined in math.h
-#ifndef M_PI
-    static const double M_PI = 3.14159265358979323846;
-#endif // M_PI
-
 // ROPs which don't have standard names (see "Ternary Raster Operations" in the
 // MSDN docs for how this and other numbers in wxDC::Blit() are obtained)
 #define DSTCOPY 0x00AA0029      // a.k.a. NOP operation
@@ -1911,8 +1905,11 @@ bool wxDC::DoBlit(wxCoord xdest, wxCoord ydest,
 
     WXMICROWIN_CHECK_HDC_RET(false)
 
+    // if either the source or destination has alpha channel, we must use
+    // AlphaBlt() as other function don't handle it correctly
     const wxBitmap& bmpSrc = source->m_selectedBitmap;
-    if ( bmpSrc.Ok() && bmpSrc.HasAlpha() )
+    if ( bmpSrc.Ok() && (bmpSrc.HasAlpha() ||
+            (m_selectedBitmap.Ok() && m_selectedBitmap.HasAlpha())) )
     {
         if ( AlphaBlt(GetHdc(), xdest, ydest, width, height,
                       GetHdcOf(*source), bmpSrc) )
@@ -2458,6 +2455,7 @@ static bool AlphaBlt(HDC hdcDst,
 #else // !wxHAVE_RAW_BITMAP
     // no wxAlphaBlend() neither, fall back to using simple BitBlt() (we lose
     // alpha but at least something will be shown like this)
+    wxUnusedVar(bmp);
     return false;
 #endif // wxHAVE_RAW_BITMAP
 }