for (map<RGBA, RGBA>::const_iterator i = _colours.begin(); i != _colours.end(); ++i) {
xmlpp::Node* node = root->add_child("Colour");
i->first.as_xml (node->add_child("From"));
for (map<RGBA, RGBA>::const_iterator i = _colours.begin(); i != _colours.end(); ++i) {
xmlpp::Node* node = root->add_child("Colour");
i->first.as_xml (node->add_child("From"));