public MapViewer(Composite parent, int style) {
if( (style & SWT.MULTI) == SWT.MULTI ){
viewport = new ViewportPaneTiledSWT(parent, style, this );
}
else if( (style & SWT.SINGLE) == SWT.SINGLE){
viewport = new ViewportPaneSWT(parent, style, this );
}
else {
viewport = new ViewportPaneSWT(parent, this );
}
}