code: public boolean checkIntensity( boolean insideDark , double threshold ) {
  		if( insideDark )
  			return averageOutside-averageInside >= threshold;
  		else
  			return averageInside-averageOutside >= threshold;
  	}
docs: Checks the edge intensity against a threshold.
  
  dark: outside-inside &ge; threshold
  light: inside-outside &ge; threshold
  
  @param insideDark is the inside of the polygon supposed to be dark or light?
  @param threshold threshold for average difference
  @return true if the edge intensity is significant enough