private List<IReactionGenerator> makeReactionGenerators() {
List<IReactionGenerator> generators = new ArrayList<IReactionGenerator>();
// generate the bounds first, so that they are to the back
if (debug) {
generators.add(new BoundsGenerator());
}
generators.add(new ReactionBoxGenerator());
generators.add(new ReactionArrowGenerator());
generators.add(new ReactionPlusGenerator());
generators.add(new ReactantsBoxGenerator());