555 

   556 bool QDirectFBPixmapData::scroll(int dx, int dy, const QRect &rect)

   557 {

   558     if (!dfbSurface) {

   559         return false;

   560     }

   561     unlockSurface();

   562     DFBResult result = dfbSurface->SetBlittingFlags(dfbSurface, DSBLIT_NOFX);

   563     if (result != DFB_OK) {

   564         DirectFBError("QDirectFBPixmapData::scroll", result);

   565         return false;

   566     }

   567     result = dfbSurface->SetPorterDuff(dfbSurface, DSPD_NONE);

   568     if (result != DFB_OK) {

   569         DirectFBError("QDirectFBPixmapData::scroll", result);

   570         return false;

   571     }

   572 

   573     const DFBRectangle source = { rect.x(), rect.y(), rect.width(), rect.height() };

   574     result = dfbSurface->Blit(dfbSurface, dfbSurface, &source, source.x + dx, source.y + dy);

   575     if (result != DFB_OK) {

   576         DirectFBError("QDirectFBPixmapData::scroll", result);

   577         return false;

   578     }

   579 

   580     return true;

   581 }

   582