code: protected int getRequiredPoints(ValueDimension dim) {
  		int requiredPointsPerTick = getGraphics().getFontMetrics().getHeight();
  		if(dim == ValueDimension.X) {
  			int first = getGraphics().getFontMetrics().stringWidth(String.format(getTickInfo(dim).getFormat(), getTickInfo(dim).getFirstTick()));
  			int last = getGraphics().getFontMetrics().stringWidth(String.format(getTickInfo(dim).getFormat(), getTickInfo(dim).getLastTick()));
  			requiredPointsPerTick = Math.max(first, last)+2;
  		} 
  		return requiredPointsPerTick*getTickInfo(dim).getTickNumber();
  	}
docs: Determines the required space (in points) for painting ticks for the coordinate axis of the given dimension.
  The basic assumption here is, that the first dimension (X) is drawed horizontally and the second dimension (Y) is drawed vertically.
  @param dim Reference dimension for space calculation
  @return Required points for painting tick information