text: 'use strict';
  
  //##############################################################################
  // GLOBAL CONSTANTS
  const tab      = 8;
  const tau      = Math.PI * 2;
  const radius   = 20;
  const diameter = radius * 2 + 1;
  const column   = diameter * 2;
  const edge     = column * 2;
  const width    = edge;
  const height   = edge;
  const area     = edge * edge;
  const x0       = column;
  const y0       = column;
  const ex       = diameter;
  const ey       = 0;
  const interval = {minimum:20,maximum:30,increment:10};
  
  const font = '16px serif';
  
  const id = {
  	figure1a:{
  		canvas:'figure 1a canvas',
  		title: 'figure 1a title',
  		text:  'figure 1a text',
  		menu:  'figure 1a menu',
  	}
  }
  const color = {
  	actual  :'#ff0000',
  	fixation:'#00ff00',
  	grid    :'#555555',
  	vector  :'#00ffff',
  };
  
  const xyTwitch = {
  	// Original data generated by duty.py
  	index:0,
  	size: 138,
  	data: [
  		[-11,  16], [ -5,  -2], [ -8, -14], [ -8,   4], [ -2,  -8], [  4, -11],
  		[-11,   1], [ 13,  10], [ -8,  -2], [  4,  16], [ -2,  16], [ 19,  -2],
  		[ 10,   7], [ -8,  13], [-17,  -8], [ 13, -11], [ 13,  -2], [-11, -11],
  		[  7,  -5], [  4,  -2], [ 10, -17], [ 16,  10], [ 13, -14], [  1,   1],
  		[ 10,  10], [ -2,   4], [ -5, -11], [ 10,  -2], [ 10,  -5], [ -5,   1],
  		[ -2,  -2], [  1,   7], [ 16,  -5], [ -8,  16], [-14,  -8], [  1,  -8],
  		[  1, -14], [-14,  -5], [-14,   7], [-11,  13], [  7, -14], [  4,   4],
  		[-14,  -2], [ 10,  13], [-11,  10], [ 10, -11], [  7,   4], [-17,  10],
  		[ 10,  -8], [  4, -14], [  4,  -5], [ -2,   7], [-17,  -2], [ -8,   1],
  		[ 10,  16], [-11, -14], [  4,   1], [-11,   4], [  4,  19], [  4,  10],
  		[-14,  10], [  4,   7], [ -5,  16], [  1, -17], [ 16,   4], [  1,  -2],
  		[-11,  -8], [ 13,   7], [ -2,  10], [  7,  13], [  1,  10], [ 13,   1],
  		[ 19,   1], [  7,  -8], [ -5, -14], [  7,   7], [  4, -17], [-14,   4],
  		[ -5,   7], [ 16,  -8], [-17,  -5], [  1,  19], [ -5, -17], [-11,  -5],
  		[ -2, -17], [ -8,   7], [ -5,   4], [ 19,   4], [-14, -11], [ 13,  -5],
  		[ -5,  -8], [  1,  13], [ 13,   4], [ -5,  13], [ -5,  -5], [ -2,   1],
  		[  1, -11], [ -8, -11], [  7,  -2], [  7,  16], [ -2, -14], [-11,   7],
  		[ -2,  13], [  4,  13], [-11,  -2], [ 16, -11], [  4,  -8], [ -2,  19],
  		[ 19,  -5], [  1,  -5], [ 13,  13], [ 10, -14], [ 16,  -2], [-14,   1],
  		[-17,   1], [ -8,  -8], [  7, -11], [ 13,  -8], [ -2,  -5], [ -5,  10],
  		[-14, -14], [  1,  16], [  7, -17], [  7,   1], [-17,   7], [ -5,  19],
  		[  1,   4], [ -8,  -5], [ 16,   1], [ -8, -17], [ 16,   7], [ 10,   4],
  		[-17,   4], [-14,  13], [ -8,  10], [ 10,   1], [  7,  10], [ -2, -11],
  
  		// --- duplicate
  
  		[-11,  16], [ -5,  -2], [ -8, -14], [ -8,   4], [ -2,  -8], [  4, -11],
  		[-11,   1], [ 13,  10], [ -8,  -2], [  4,  16], [ -2,  16], [ 19,  -2],
  		[ 10,   7], [ -8,  13], [-17,  -8], [ 13, -11], [ 13,  -2], [-11, -11],
  		[  7,  -5], [  4,  -2], [ 10, -17], [ 16,  10], [ 13, -14], [  1,   1],
  		[ 10,  10], [ -2,   4], [ -5, -11], [ 10,  -2], [ 10,  -5], [ -5,   1],
  		[ -2,  -2], [  1,   7], [ 16,  -5], [ -8,  16], [-14,  -8], [  1,  -8],
  		[  1, -14], [-14,  -5], [-14,   7], [-11,  13], [  7, -14], [  4,   4],
  		[-14,  -2], [ 10,  13], [-11,  10], [ 10, -11], [  7,   4], [-17,  10],
  		[ 10,  -8], [  4, -14], [  4,  -5], [ -2,   7], [-17,  -2], [ -8,   1],
  		[ 10,  16], [-11, -14], [  4,   1], [-11,   4], [  4,  19], [  4,  10],
  		[-14,  10], [  4,   7], [ -5,  16], [  1, -17], [ 16,   4], [  1,  -2],
  		[-11,  -8], [ 13,   7], [ -2,  10], [  7,  13], [  1,  10], [ 13,   1],
  		[ 19,   1], [  7,  -8], [ -5, -14], [  7,   7], [  4, -17], [-14,   4],
  		[ -5,   7], [ 16,  -8], [-17,  -5], [  1,  19], [ -5, -17], [-11,  -5],
  		[ -2, -17], [ -8,   7], [ -5,   4], [ 19,   4], [-14, -11], [ 13,  -5],
  		[ -5,  -8], [  1,  13], [ 13,   4], [ -5,  13], [ -5,  -5], [ -2,   1],
  		[  1, -11], [ -8, -11], [  7,  -2], [  7,  16], [ -2, -14], [-11,   7],
  		[ -2,  13], [  4,  13], [-11,  -2], [ 16, -11], [  4,  -8], [ -2,  19],
  		[ 19,  -5], [  1,  -5], [ 13,  13], [ 10, -14], [ 16,  -2], [-14,   1],
  		[-17,   1], [ -8,  -8], [  7, -11], [ 13,  -8], [ -2,  -5], [ -5,  10],
  		[-14, -14], [  1,  16], [  7, -17], [  7,   1], [-17,   7], [ -5,  19],
  		[  1,   4], [ -8,  -5], [ 16,   1], [ -8, -17], [ 16,   7], [ 10,   4],
  		[-17,   4], [-14,  13], [ -8,  10], [ 10,   1], [  7,  10], [ -2, -11],
  	]
  };
  