+ wxCHECK_MSG( Ok(), (unsigned char *)NULL, wxT("invalid image") );
+
+ return M_IMGDATA->m_alpha;
+}
+
+// ----------------------------------------------------------------------------
+// mask support
+// ----------------------------------------------------------------------------
+
+void wxImage::SetMaskColour( unsigned char r, unsigned char g, unsigned char b )
+{
+ wxCHECK_RET( Ok(), wxT("invalid image") );
+
+ M_IMGDATA->m_maskRed = r;
+ M_IMGDATA->m_maskGreen = g;
+ M_IMGDATA->m_maskBlue = b;
+ M_IMGDATA->m_hasMask = true;
+}
+
+unsigned char wxImage::GetMaskRed() const
+{
+ wxCHECK_MSG( Ok(), 0, wxT("invalid image") );
+
+ return M_IMGDATA->m_maskRed;
+}
+
+unsigned char wxImage::GetMaskGreen() const
+{
+ wxCHECK_MSG( Ok(), 0, wxT("invalid image") );
+
+ return M_IMGDATA->m_maskGreen;
+}
+
+unsigned char wxImage::GetMaskBlue() const
+{
+ wxCHECK_MSG( Ok(), 0, wxT("invalid image") );
+
+ return M_IMGDATA->m_maskBlue;
+}
+
+void wxImage::SetMask( bool mask )
+{
+ wxCHECK_RET( Ok(), wxT("invalid image") );
+
+ M_IMGDATA->m_hasMask = mask;
+}
+
+bool wxImage::HasMask() const
+{
+ wxCHECK_MSG( Ok(), false, wxT("invalid image") );
+
+ return M_IMGDATA->m_hasMask;
+}
+
+int wxImage::GetWidth() const
+{
+ wxCHECK_MSG( Ok(), 0, wxT("invalid image") );
+
+ return M_IMGDATA->m_width;
+}
+
+int wxImage::GetHeight() const
+{
+ wxCHECK_MSG( Ok(), 0, wxT("invalid image") );
+
+ return M_IMGDATA->m_height;
+}
+
+bool wxImage::SetMaskFromImage(const wxImage& mask,
+ unsigned char mr, unsigned char mg, unsigned char mb)
+{
+ // check that the images are the same size
+ if ( (M_IMGDATA->m_height != mask.GetHeight() ) || (M_IMGDATA->m_width != mask.GetWidth () ) )
+ {
+ wxLogError( _("Image and Mask have different sizes") );
+ return false;
+ }
+
+ // find unused colour
+ unsigned char r,g,b ;
+ if (!FindFirstUnusedColour(&r, &g, &b))