#if wxUSE_IMAGE
-bool wxDIB::Create(const wxImage& image)
+bool wxDIB::Create(const wxImage& image, PixelFormat pf)
{
wxCHECK_MSG( image.Ok(), false, wxT("invalid wxImage in wxDIB ctor") );
unsigned char *dstLineStart = (unsigned char *)m_data;
for ( int y = 0; y < h; y++ )
{
- // copy one DIB line
+ // Copy one DIB line. Note that RGB components order is reversed in
+ // Windows bitmaps compared to wxImage and is actually BGR.
unsigned char *dst = dstLineStart;
if ( alpha )
{
- for ( int x = 0; x < w; x++ )
+ int x;
+
+ switch ( pf )
{
- // RGB order is reversed, and we need to premultiply
- // all channels by alpha value for use with ::AlphaBlend.
- const unsigned char a = *alpha++;
- *dst++ = (unsigned char)((src[2] * a + 127) / 255);
- *dst++ = (unsigned char)((src[1] * a + 127) / 255);
- *dst++ = (unsigned char)((src[0] * a + 127) / 255);
- *dst++ = a;
- src += 3;
+ case PixelFormat_PreMultiplied:
+ // Pre-multiply pixel values so that the DIB could be used
+ // with ::AlphaBlend().
+ for ( x = 0; x < w; x++ )
+ {
+ const unsigned char a = *alpha++;
+ *dst++ = (unsigned char)((src[2] * a + 127) / 255);
+ *dst++ = (unsigned char)((src[1] * a + 127) / 255);
+ *dst++ = (unsigned char)((src[0] * a + 127) / 255);
+ *dst++ = a;
+ src += 3;
+ }
+ break;
+
+ case PixelFormat_NotPreMultiplied:
+ // Just copy pixel data without changing it.
+ for ( x = 0; x < w; x++ )
+ {
+ *dst++ = src[2];
+ *dst++ = src[1];
+ *dst++ = src[0];
+
+ *dst++ = *alpha++;
+ src += 3;
+ }
+ break;
}
+
}
else // no alpha channel
{
for ( int x = 0; x < w; x++ )
{
- // RGB order is reversed.
*dst++ = src[2];
*dst++ = src[1];
*dst++ = src[0];