makeImpl : function(test, maskPattern) {
    this.moduleCount = this.typeNumber * 4 + 17;
    this.modules = new Array(this.moduleCount);
    for (var row = 0; row < this.moduleCount; row++) {
      this.modules[row] = new Array(this.moduleCount);
      for (var col = 0; col < this.moduleCount; col++) {
        this.modules[row][col] = null;//(col + row) % 3;
      }
    }
    
    this.setupPositionProbePattern(0, 0);// 位置探测图形
    this.setupPositionProbePattern(this.moduleCount - 7, 0);// 位置探测图形
    this.setupPositionProbePattern(0, this.moduleCount - 7);// 位置探测图形
    this.setupPositionAdjustPattern(); // 校正图形
    this.setupTimingPattern(); // 定位图形（坐标轴）
    this.setupTypeInfo(test, maskPattern); // 版本信息

    if (this.typeNumber >= 7) {
      this.setupTypeNumber(test);
    }

    if (this.dataCache == null) {
      this.dataCache = QRCode.createData(this.typeNumber, this.errorCorrectLevel, this.dataList); // 生成数据
    }

    this.mapData(this.dataCache, maskPattern); // 加入掩码
  },

var createCanvas  = function(){
      // create the qrcode itself
      var qrcode  = new QRCode(options.typeNumber, options.correctLevel);
      qrcode.addData(options.text);
      qrcode.make();

      // create canvas element
      var canvas  = document.createElement('canvas');
      canvas.width  = options.width;
      canvas.height = options.height;
      var ctx   = canvas.getContext('2d');

      // compute tileW/tileH based on options.width/options.height
      var tileW = options.width  / qrcode.getModuleCount();
      var tileH = options.height / qrcode.getModuleCount();

      // draw in the canvas
      for( var row = 0; row < qrcode.getModuleCount(); row++ ){
        for( var col = 0; col < qrcode.getModuleCount(); col++ ){
          ctx.fillStyle = qrcode.isDark(row, col) ? options.foreground : options.background;
          var w = (Math.ceil((col+1)*tileW) - Math.floor(col*tileW));
          var h = (Math.ceil((row+1)*tileH) - Math.floor(row*tileH));
          ctx.fillRect(Math.round(col*tileW),Math.round(row*tileH), w, h);  
        } 
      }

      // return just built canvas
      return canvas;
    }