en/builder/src/echarts3/coord/axisHelper.js

import { __DEV__ } from '../config';
import * as zrUtil from 'zrender/src/core/util';
import * as textContain from 'zrender/src/contain/text';
import OrdinalScale from '../scale/Ordinal';
import IntervalScale from '../scale/Interval';
import Scale from '../scale/Scale';
import * as numberUtil from '../util/number';
import '../scale/Time';
import '../scale/Log';
/**
 * Get axis scale extent before niced.
 * Item of returned array can only be number (including Infinity and NaN).
 */

export function getScaleExtent(scale, model) {
  var scaleType = scale.type;
  var min = model.getMin();
  var max = model.getMax();
  var fixMin = min != null;
  var fixMax = max != null;
  var originalExtent = scale.getExtent();
  var axisDataLen;
  var boundaryGap;
  var span;

  if (scaleType === 'ordinal') {
    axisDataLen = (model.get('data') || []).length;
  } else {
    boundaryGap = model.get('boundaryGap');

    if (!zrUtil.isArray(boundaryGap)) {
      boundaryGap = [boundaryGap || 0, boundaryGap || 0];
    }

    if (typeof boundaryGap[0] === 'boolean') {
      boundaryGap = [0, 0];
    }

    boundaryGap[0] = numberUtil.parsePercent(boundaryGap[0], 1);
    boundaryGap[1] = numberUtil.parsePercent(boundaryGap[1], 1);
    span = originalExtent[1] - originalExtent[0] || Math.abs(originalExtent[0]);
  } // Notice: When min/max is not set (that is, when there are null/undefined,
  // which is the most common case), these cases should be ensured:
  // (1) For 'ordinal', show all axis.data.
  // (2) For others:
  //      + `boundaryGap` is applied (if min/max set, boundaryGap is
  //      disabled).
  //      + If `needCrossZero`, min/max should be zero, otherwise, min/max should
  //      be the result that originalExtent enlarged by boundaryGap.
  // (3) If no data, it should be ensured that `scale.setBlank` is set.
  // FIXME
  // (1) When min/max is 'dataMin' or 'dataMax', should boundaryGap be able to used?
  // (2) When `needCrossZero` and all data is positive/negative, should it be ensured
  // that the results processed by boundaryGap are positive/negative?


  if (min == null) {
    min = scaleType === 'ordinal' ? axisDataLen ? 0 : NaN : originalExtent[0] - boundaryGap[0] * span;
  }

  if (max == null) {
    max = scaleType === 'ordinal' ? axisDataLen ? axisDataLen - 1 : NaN : originalExtent[1] + boundaryGap[1] * span;
  }

  if (min === 'dataMin') {
    min = originalExtent[0];
  } else if (typeof min === 'function') {
    min = min({
      min: originalExtent[0],
      max: originalExtent[1]
    });
  }

  if (max === 'dataMax') {
    max = originalExtent[1];
  } else if (typeof max === 'function') {
    max = max({
      min: originalExtent[0],
      max: originalExtent[1]
    });
  }

  (min == null || !isFinite(min)) && (min = NaN);
  (max == null || !isFinite(max)) && (max = NaN);
  scale.setBlank(zrUtil.eqNaN(min) || zrUtil.eqNaN(max)); // Evaluate if axis needs cross zero

  if (model.getNeedCrossZero()) {
    // Axis is over zero and min is not set
    if (min > 0 && max > 0 && !fixMin) {
      min = 0;
    } // Axis is under zero and max is not set


    if (min < 0 && max < 0 && !fixMax) {
      max = 0;
    }
  }

  return [min, max];
}
export function niceScaleExtent(scale, model) {
  var extent = getScaleExtent(scale, model);
  var fixMin = model.getMin() != null;
  var fixMax = model.getMax() != null;
  var splitNumber = model.get('splitNumber');

  if (scale.type === 'log') {
    scale.base = model.get('logBase');
  }

  var scaleType = scale.type;
  scale.setExtent(extent[0], extent[1]);
  scale.niceExtent({
    splitNumber: splitNumber,
    fixMin: fixMin,
    fixMax: fixMax,
    minInterval: scaleType === 'interval' || scaleType === 'time' ? model.get('minInterval') : null,
    maxInterval: scaleType === 'interval' || scaleType === 'time' ? model.get('maxInterval') : null
  }); // If some one specified the min, max. And the default calculated interval
  // is not good enough. He can specify the interval. It is often appeared
  // in angle axis with angle 0 - 360. Interval calculated in interval scale is hard
  // to be 60.
  // FIXME

  var interval = model.get('interval');

  if (interval != null) {
    scale.setInterval && scale.setInterval(interval);
  }
}
/**
 * @param {module:echarts/model/Model} model
 * @param {string} [axisType] Default retrieve from model.type
 * @return {module:echarts/scale/*}
 */

export function createScaleByModel(model, axisType) {
  axisType = axisType || model.get('type');

  if (axisType) {
    switch (axisType) {
      // Buildin scale
      case 'category':
        return new OrdinalScale(model.getCategories(), [Infinity, -Infinity]);

      case 'value':
        return new IntervalScale();
      // Extended scale, like time and log

      default:
        return (Scale.getClass(axisType) || IntervalScale).create(model);
    }
  }
}
/**
 * Check if the axis corss 0
 */

export function ifAxisCrossZero(axis) {
  var dataExtent = axis.scale.getExtent();
  var min = dataExtent[0];
  var max = dataExtent[1];
  return !(min > 0 && max > 0 || min < 0 && max < 0);
}
/**
 * @param {Array.<number>} tickCoords In axis self coordinate.
 * @param {Array.<string>} labels
 * @param {string} font
 * @param {number} axisRotate 0: towards right horizontally, clock-wise is negative.
 * @param {number} [labelRotate=0] 0: towards right horizontally, clock-wise is negative.
 * @return {number}
 */

export function getAxisLabelInterval(tickCoords, labels, font, axisRotate, labelRotate) {
  var textSpaceTakenRect;
  var autoLabelInterval = 0;
  var accumulatedLabelInterval = 0;
  var rotation = (axisRotate - labelRotate) / 180 * Math.PI;
  var step = 1;

  if (labels.length > 40) {
    // Simple optimization for large amount of labels
    step = Math.floor(labels.length / 40);
  }

  for (var i = 0; i < tickCoords.length; i += step) {
    var tickCoord = tickCoords[i]; // Not precise, do not consider align and vertical align
    // and each distance from axis line yet.

    var rect = textContain.getBoundingRect(labels[i], font, 'center', 'top');
    rect.x += tickCoord * Math.cos(rotation);
    rect.y += tickCoord * Math.sin(rotation); // Magic number

    rect.width *= 1.3;
    rect.height *= 1.3;

    if (!textSpaceTakenRect) {
      textSpaceTakenRect = rect.clone();
    } // There is no space for current label;
    else if (textSpaceTakenRect.intersect(rect)) {
        accumulatedLabelInterval++;
        autoLabelInterval = Math.max(autoLabelInterval, accumulatedLabelInterval);
      } else {
        textSpaceTakenRect.union(rect); // Reset

        accumulatedLabelInterval = 0;
      }
  }

  if (autoLabelInterval === 0 && step > 1) {
    return step;
  }

  return (autoLabelInterval + 1) * step - 1;
}
/**
 * @param {Object} axis
 * @param {Function} labelFormatter
 * @return {Array.<string>}
 */

export function getFormattedLabels(axis, labelFormatter) {
  var scale = axis.scale;
  var labels = scale.getTicksLabels();
  var ticks = scale.getTicks();

  if (typeof labelFormatter === 'string') {
    labelFormatter = function (tpl) {
      return function (val) {
        return tpl.replace('{value}', val != null ? val : '');
      };
    }(labelFormatter); // Consider empty array


    return zrUtil.map(labels, labelFormatter);
  } else if (typeof labelFormatter === 'function') {
    return zrUtil.map(ticks, function (tick, idx) {
      return labelFormatter(getAxisRawValue(axis, tick), idx);
    }, this);
  } else {
    return labels;
  }
}
export function getAxisRawValue(axis, value) {
  // In category axis with data zoom, tick is not the original
  // index of axis.data. So tick should not be exposed to user
  // in category axis.
  return axis.type === 'category' ? axis.scale.getLabel(value) : value;
}