@Override public void perform(final org.nlogo.nvm.Context context) { Turtle turtle = argEvalTurtle(context, 0); if (turtle.id() == -1) { throw new EngineException( context, this, I18N.errorsJ().getN("org.nlogo.$common.thatAgentIsDead", turtle.classDisplayName())); } world.observer().setPerspective(PerspectiveJ.RIDE(), turtle); context.ip = next; }