zh/builder/src/echarts3/chart/graph/createView.js

// FIXME Where to create the simple view coordinate system
import View from '../../coord/View';
import { getLayoutRect } from '../../util/layout';
import * as bbox from 'zrender/src/core/bbox';

function getViewRect(seriesModel, api, aspect) {
  var option = seriesModel.getBoxLayoutParams();
  option.aspect = aspect;
  return getLayoutRect(option, {
    width: api.getWidth(),
    height: api.getHeight()
  });
}

export default function (ecModel, api) {
  var viewList = [];
  ecModel.eachSeriesByType('graph', function (seriesModel) {
    var coordSysType = seriesModel.get('coordinateSystem');

    if (!coordSysType || coordSysType === 'view') {
      var data = seriesModel.getData();
      var positions = data.mapArray(function (idx) {
        var itemModel = data.getItemModel(idx);
        return [+itemModel.get('x'), +itemModel.get('y')];
      });
      var min = [];
      var max = [];
      bbox.fromPoints(positions, min, max); // If width or height is 0

      if (max[0] - min[0] === 0) {
        max[0] += 1;
        min[0] -= 1;
      }

      if (max[1] - min[1] === 0) {
        max[1] += 1;
        min[1] -= 1;
      }

      var aspect = (max[0] - min[0]) / (max[1] - min[1]); // FIXME If get view rect after data processed?

      var viewRect = getViewRect(seriesModel, api, aspect); // Position may be NaN, use view rect instead

      if (isNaN(aspect)) {
        min = [viewRect.x, viewRect.y];
        max = [viewRect.x + viewRect.width, viewRect.y + viewRect.height];
      }

      var bbWidth = max[0] - min[0];
      var bbHeight = max[1] - min[1];
      var viewWidth = viewRect.width;
      var viewHeight = viewRect.height;
      var viewCoordSys = seriesModel.coordinateSystem = new View();
      viewCoordSys.zoomLimit = seriesModel.get('scaleLimit');
      viewCoordSys.setBoundingRect(min[0], min[1], bbWidth, bbHeight);
      viewCoordSys.setViewRect(viewRect.x, viewRect.y, viewWidth, viewHeight); // Update roam info

      viewCoordSys.setCenter(seriesModel.get('center'));
      viewCoordSys.setZoom(seriesModel.get('zoom'));
      viewList.push(viewCoordSys);
    }
  });
  return viewList;
}