public static void populateModel(TestbedModel model) {
// particles
model.addCategory("Particles");
model.addTest(new BulletTest());
model.addTest(new DamBreak());
model.addTest(new DrawingParticles());
model.addTest(new LiquidTimer());
model.addTest(new WaveMachine());
model.addTest(new Particles());
model.addCategory("Featured");