@Override public void perform(final Context context) throws LogoException { int numberOfTurtles = argEvalIntValue(context, 0); if (numberOfTurtles > 0) { AgentSet agentset = new ArrayAgentSet(Turtle.class, numberOfTurtles, false, world); AgentSet breed = breedName == NO_BREED ? world.turtles() : world.getBreed(breedName); for (int i = 0; i < numberOfTurtles; i++) { Turtle turtle = world.createTurtle(breed); turtle.colorDouble(Double.valueOf(10.0 * i + 5.0)); turtle.heading((360.0 * i) / numberOfTurtles); agentset.add(turtle); workspace.joinForeverButtons(turtle); } context.runExclusiveJob(agentset, next); } context.ip = offset; }