+ case kEventWindowGetRegion :
+ {
+ if ( toplevelWindow->GetBackgroundStyle() == wxBG_STYLE_TRANSPARENT )
+ {
+ WindowRegionCode windowRegionCode ;
+
+ // Fetch the region code that is being queried
+ GetEventParameter( event,
+ kEventParamWindowRegionCode,
+ typeWindowRegionCode, NULL,
+ sizeof windowRegionCode, NULL,
+ &windowRegionCode ) ;
+
+ // If it is the opaque region code then set the
+ // region to empty and return noErr to stop event
+ // propagation
+ if ( windowRegionCode == kWindowOpaqueRgn ) {
+ RgnHandle region;
+ GetEventParameter( event,
+ kEventParamRgnHandle,
+ typeQDRgnHandle, NULL,
+ sizeof region, NULL,
+ ®ion) ;
+ SetEmptyRgn(region) ;
+ result = noErr ;
+ }
+ }
+ }
+ break ;
+