- // the mask returned by GetIconInfo() is inversed compared to the usual
- // wxWin convention
- refData->SetMask(wxInvertMask(iconInfo.hbmMask, w, h));
-
+#if wxUSE_WXDIB
+ // If the icon is 32 bits per pixel then it may have alpha channel data,
+ // although there are some icons that are 32 bpp but have no alpha... So
+ // convert to a DIB and manually check the 4th byte for each pixel.
+ BITMAP bm;
+ if ( ::GetObject(iconInfo.hbmColor, sizeof(BITMAP), (LPVOID)&bm)
+ && bm.bmBitsPixel == 32)
+ {
+ wxDIB dib(iconInfo.hbmColor);
+ if (dib.IsOk())
+ {
+ unsigned char* pixels = dib.GetData();
+ for (int idx=0; idx<w*h*4; idx+=4)
+ {
+ if (pixels[idx+3] != 0)
+ {
+ // If there is an alpha byte that is non-zero then set the
+ // alpha flag and bail out of the loop.
+ refData->m_hasAlpha = true;
+ break;
+ }
+ }
+ }
+ }
+#endif
+ if ( !refData->m_hasAlpha )
+ {
+ // the mask returned by GetIconInfo() is inverted compared to the usual
+ // wxWin convention
+ refData->SetMask(wxInvertMask(iconInfo.hbmMask, w, h));
+ }