return M_IMGDATA->m_alpha;
}
+void wxImage::InitAlpha()
+{
+ wxCHECK_RET( !HasAlpha(), wxT("image already has an alpha channel") );
+
+ // initialize memory for alpha channel
+ SetAlpha();
+
+ unsigned char *alpha = M_IMGDATA->m_alpha;
+ const size_t lenAlpha = M_IMGDATA->m_width * M_IMGDATA->m_height;
+
+ static const unsigned char ALPHA_TRANSPARENT = 0;
+ static const unsigned char ALPHA_OPAQUE = 0xff;
+ if ( HasMask() )
+ {
+ // use the mask to initialize the alpha channel.
+ const unsigned char * const alphaEnd = alpha + lenAlpha;
+
+ const unsigned char mr = M_IMGDATA->m_maskRed;
+ const unsigned char mg = M_IMGDATA->m_maskGreen;
+ const unsigned char mb = M_IMGDATA->m_maskBlue;
+ for ( unsigned char *src = M_IMGDATA->m_data;
+ alpha < alphaEnd;
+ src += 3, alpha++ )
+ {
+ *alpha = (src[0] == mr && src[1] == mg && src[2] == mb)
+ ? ALPHA_TRANSPARENT
+ : ALPHA_OPAQUE;
+ }
+
+ M_IMGDATA->m_hasMask = false;
+ }
+ else // no mask
+ {
+ // make the image fully opaque
+ memset(alpha, ALPHA_OPAQUE, lenAlpha);
+ }
+}
+
// ----------------------------------------------------------------------------
// mask support
// ----------------------------------------------------------------------------
int wxImage::GetOptionInt(const wxString& name) const
{
- wxCHECK_MSG( Ok(), 0, wxT("invalid image") );
-
return wxAtoi(GetOption(name));
}