src/coord/Axis.ts - echarts - Git at Google

 /*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

 import {each, map} from 'zrender/src/core/util';
 import {linearMap, getPixelPrecision, round} from '../util/number';
 import {
     createAxisTicks,
     createAxisLabels,
     calculateCategoryInterval
 } from './axisTickLabelBuilder';
 import Scale from '../scale/Scale';
 import { DimensionName, ScaleDataValue, ScaleTick } from '../util/types';
 import OrdinalScale from '../scale/Ordinal';
 import Model from '../model/Model';
 import { AxisBaseOption, OptionAxisType } from './axisCommonTypes';
 import { AxisBaseModel } from './AxisBaseModel';

 const NORMALIZED_EXTENT = [0, 1] as [number, number];

 interface TickCoord {
     coord: number;
     // That is `scaleTick.value`.
     tickValue?: ScaleTick['value'];
 }

 /**
  * Base class of Axis.
  */
 class Axis {

     /**
      * Axis type
      *  - 'category'
      *  - 'value'
      *  - 'time'
      *  - 'log'
      */
     type: OptionAxisType;

     // Axis dimension. Such as 'x', 'y', 'z', 'angle', 'radius'.
     readonly dim: DimensionName;

     // Axis scale
     scale: Scale;

     private _extent: [number, number];

     // Injected outside
     model: AxisBaseModel;
     onBand: AxisBaseOption['boundaryGap'] = false;
     inverse: AxisBaseOption['inverse'] = false;


     constructor(dim: DimensionName, scale: Scale, extent: [number, number]) {
         this.dim = dim;
         this.scale = scale;
         this._extent = extent || [0, 0];
     }

     /**
      * If axis extent contain given coord
      */
     contain(coord: number): boolean {
         const extent = this._extent;
         const min = Math.min(extent[0], extent[1]);
         const max = Math.max(extent[0], extent[1]);
         return coord >= min && coord <= max;
     }

     /**
      * If axis extent contain given data
      */
     containData(data: ScaleDataValue): boolean {
         return this.scale.contain(data);
     }

     /**
      * Get coord extent.
      */
     getExtent(): [number, number] {
         return this._extent.slice() as [number, number];
     }

     /**
      * Get precision used for formatting
      */
     getPixelPrecision(dataExtent?: [number, number]): number {
         return getPixelPrecision(
             dataExtent || this.scale.getExtent(),
             this._extent
         );
     }

     /**
      * Set coord extent
      */
     setExtent(start: number, end: number): void {
         const extent = this._extent;
         extent[0] = start;
         extent[1] = end;
     }

     /**
      * Convert data to coord. Data is the rank if it has an ordinal scale
      */
     dataToCoord(data: ScaleDataValue, clamp?: boolean): number {
         let extent = this._extent;
         const scale = this.scale;
         data = scale.normalize(data);

         if (this.onBand && scale.type === 'ordinal') {
             extent = extent.slice() as [number, number];
             fixExtentWithBands(extent, (scale as OrdinalScale).count());
         }

         return linearMap(data, NORMALIZED_EXTENT, extent, clamp);
     }

     /**
      * Convert coord to data. Data is the rank if it has an ordinal scale
      */
     coordToData(coord: number, clamp?: boolean): number {
         let extent = this._extent;
         const scale = this.scale;

         if (this.onBand && scale.type === 'ordinal') {
             extent = extent.slice() as [number, number];
             fixExtentWithBands(extent, (scale as OrdinalScale).count());
         }

         const t = linearMap(coord, extent, NORMALIZED_EXTENT, clamp);

         return this.scale.scale(t);
     }

     /**
      * Convert pixel point to data in axis
      */
     pointToData(point: number[], clamp?: boolean): number {
         // Should be implemented in derived class if necessary.
         return;
     }

     /**
      * Different from `zrUtil.map(axis.getTicks(), axis.dataToCoord, axis)`,
      * `axis.getTicksCoords` considers `onBand`, which is used by
      * `boundaryGap:true` of category axis and splitLine and splitArea.
      * @param opt.tickModel default: axis.model.getModel('axisTick')
      * @param opt.clamp If `true`, the first and the last
      *        tick must be at the axis end points. Otherwise, clip ticks
      *        that outside the axis extent.
      */
     getTicksCoords(opt?: {
         tickModel?: Model,
         clamp?: boolean
     }): TickCoord[] {
         opt = opt || {};

         const tickModel = opt.tickModel || this.getTickModel();
         const result = createAxisTicks(this, tickModel as AxisBaseModel);
         const ticks = result.ticks;

         const ticksCoords = map(ticks, function (tickVal) {
             return {
                 coord: this.dataToCoord(
                     this.scale.type === 'ordinal'
                         ? (this.scale as OrdinalScale).getRawOrdinalNumber(tickVal)
                         : tickVal
                 ),
                 tickValue: tickVal
             };
         }, this);

         const alignWithLabel = tickModel.get('alignWithLabel');

         fixOnBandTicksCoords(
             this, ticksCoords, alignWithLabel, opt.clamp
         );

         return ticksCoords;
     }

     getMinorTicksCoords(): TickCoord[][] {
         if (this.scale.type === 'ordinal') {
             // Category axis doesn't support minor ticks
             return [];
         }

         const minorTickModel = this.model.getModel('minorTick');
         let splitNumber = minorTickModel.get('splitNumber');
         // Protection.
         if (!(splitNumber > 0 && splitNumber < 100)) {
             splitNumber = 5;
         }
         const minorTicks = this.scale.getMinorTicks(splitNumber);
         const minorTicksCoords = map(minorTicks, function (minorTicksGroup) {
             return map(minorTicksGroup, function (minorTick) {
                 return {
                     coord: this.dataToCoord(minorTick),
                     tickValue: minorTick
                 };
             }, this);
         }, this);
         return minorTicksCoords;
     }

     getViewLabels(): ReturnType<typeof createAxisLabels>['labels'] {
         return createAxisLabels(this).labels;
     }

     getLabelModel(): Model<AxisBaseOption['axisLabel']> {
         return this.model.getModel('axisLabel');
     }

     /**
      * Notice here we only get the default tick model. For splitLine
      * or splitArea, we should pass the splitLineModel or splitAreaModel
      * manually when calling `getTicksCoords`.
      * In GL, this method may be overrided to:
      * `axisModel.getModel('axisTick', grid3DModel.getModel('axisTick'));`
      */
     getTickModel(): Model {
         return this.model.getModel('axisTick');
     }

     /**
      * Get width of band
      */
     getBandWidth(): number {
         const axisExtent = this._extent;
         const dataExtent = this.scale.getExtent();

         let len = dataExtent[1] - dataExtent[0] + (this.onBand ? 1 : 0);
         // Fix #2728, avoid NaN when only one data.
         len === 0 && (len = 1);

         const size = Math.abs(axisExtent[1] - axisExtent[0]);

         return Math.abs(size) / len;
     }

     /**
      * Get axis rotate, by degree.
      */
     getRotate: () => number;

     /**
      * Only be called in category axis.
      * Can be overrided, consider other axes like in 3D.
      * @return Auto interval for cateogry axis tick and label
      */
     calculateCategoryInterval(): ReturnType<typeof calculateCategoryInterval> {
         return calculateCategoryInterval(this);
     }

 }

 function fixExtentWithBands(extent: [number, number], nTick: number): void {
     const size = extent[1] - extent[0];
     const len = nTick;
     const margin = size / len / 2;
     extent[0] += margin;
     extent[1] -= margin;
 }

 // If axis has labels [1, 2, 3, 4]. Bands on the axis are
 // |---1---|---2---|---3---|---4---|.
 // So the displayed ticks and splitLine/splitArea should between
 // each data item, otherwise cause misleading (e.g., split tow bars
 // of a single data item when there are two bar series).
 // Also consider if tickCategoryInterval > 0 and onBand, ticks and
 // splitLine/spliteArea should layout appropriately corresponding
 // to displayed labels. (So we should not use `getBandWidth` in this
 // case).
 function fixOnBandTicksCoords(
     axis: Axis, ticksCoords: TickCoord[], alignWithLabel: boolean, clamp: boolean
 ) {
     const ticksLen = ticksCoords.length;

     if (!axis.onBand || alignWithLabel || !ticksLen) {
         return;
     }

     const axisExtent = axis.getExtent();
     let last;
     let diffSize;
     if (ticksLen === 1) {
         ticksCoords[0].coord = axisExtent[0];
         last = ticksCoords[1] = {coord: axisExtent[0]};
     }
     else {
         const crossLen = ticksCoords[ticksLen - 1].tickValue - ticksCoords[0].tickValue;
         const shift = (ticksCoords[ticksLen - 1].coord - ticksCoords[0].coord) / crossLen;

         each(ticksCoords, function (ticksItem) {
             ticksItem.coord -= shift / 2;
         });

         const dataExtent = axis.scale.getExtent();
         diffSize = 1 + dataExtent[1] - ticksCoords[ticksLen - 1].tickValue;

         last = {coord: ticksCoords[ticksLen - 1].coord + shift * diffSize};

         ticksCoords.push(last);
     }

     const inverse = axisExtent[0] > axisExtent[1];

     // Handling clamp.
     if (littleThan(ticksCoords[0].coord, axisExtent[0])) {
         clamp ? (ticksCoords[0].coord = axisExtent[0]) : ticksCoords.shift();
     }
     if (clamp && littleThan(axisExtent[0], ticksCoords[0].coord)) {
         ticksCoords.unshift({coord: axisExtent[0]});
     }
     if (littleThan(axisExtent[1], last.coord)) {
         clamp ? (last.coord = axisExtent[1]) : ticksCoords.pop();
     }
     if (clamp && littleThan(last.coord, axisExtent[1])) {
         ticksCoords.push({coord: axisExtent[1]});
     }

     function littleThan(a: number, b: number): boolean {
         // Avoid rounding error cause calculated tick coord different with extent.
         // It may cause an extra unecessary tick added.
         a = round(a);
         b = round(b);
         return inverse ? a > b : a < b;
     }
 }

 export default Axis;
	/*
	* Licensed to the Apache Software Foundation (ASF) under one
	* or more contributor license agreements. See the NOTICE file
	* distributed with this work for additional information
	* regarding copyright ownership. The ASF licenses this file
	* to you under the Apache License, Version 2.0 (the
	* "License"); you may not use this file except in compliance
	* with the License. You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing,
	* software distributed under the License is distributed on an
	* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
	* KIND, either express or implied. See the License for the
	* specific language governing permissions and limitations
	* under the License.
	*/

	import {each, map} from 'zrender/src/core/util';
	import {linearMap, getPixelPrecision, round} from '../util/number';
	import {
	createAxisTicks,
	createAxisLabels,
	calculateCategoryInterval
	} from './axisTickLabelBuilder';
	import Scale from '../scale/Scale';
	import { DimensionName, ScaleDataValue, ScaleTick } from '../util/types';
	import OrdinalScale from '../scale/Ordinal';
	import Model from '../model/Model';
	import { AxisBaseOption, OptionAxisType } from './axisCommonTypes';
	import { AxisBaseModel } from './AxisBaseModel';

	const NORMALIZED_EXTENT = [0, 1] as [number, number];

	interface TickCoord {
	coord: number;
	// That is `scaleTick.value`.
	tickValue?: ScaleTick['value'];
	}

	/**
	* Base class of Axis.
	*/
	class Axis {

	/**
	* Axis type
	* - 'category'
	* - 'value'
	* - 'time'
	* - 'log'
	*/
	type: OptionAxisType;

	// Axis dimension. Such as 'x', 'y', 'z', 'angle', 'radius'.
	readonly dim: DimensionName;

	// Axis scale
	scale: Scale;

	private _extent: [number, number];

	// Injected outside
	model: AxisBaseModel;
	onBand: AxisBaseOption['boundaryGap'] = false;
	inverse: AxisBaseOption['inverse'] = false;


	constructor(dim: DimensionName, scale: Scale, extent: [number, number]) {
	this.dim = dim;
	this.scale = scale;
	this._extent = extent \|\| [0, 0];
	}

	/**
	* If axis extent contain given coord
	*/
	contain(coord: number): boolean {
	const extent = this._extent;
	const min = Math.min(extent[0], extent[1]);
	const max = Math.max(extent[0], extent[1]);
	return coord >= min && coord <= max;
	}

	/**
	* If axis extent contain given data
	*/
	containData(data: ScaleDataValue): boolean {
	return this.scale.contain(data);
	}

	/**
	* Get coord extent.
	*/
	getExtent(): [number, number] {
	return this._extent.slice() as [number, number];
	}

	/**
	* Get precision used for formatting
	*/
	getPixelPrecision(dataExtent?: [number, number]): number {
	return getPixelPrecision(
	dataExtent \|\| this.scale.getExtent(),
	this._extent
	);
	}

	/**
	* Set coord extent
	*/
	setExtent(start: number, end: number): void {
	const extent = this._extent;
	extent[0] = start;
	extent[1] = end;
	}

	/**
	* Convert data to coord. Data is the rank if it has an ordinal scale
	*/
	dataToCoord(data: ScaleDataValue, clamp?: boolean): number {
	let extent = this._extent;
	const scale = this.scale;
	data = scale.normalize(data);

	if (this.onBand && scale.type === 'ordinal') {
	extent = extent.slice() as [number, number];
	fixExtentWithBands(extent, (scale as OrdinalScale).count());
	}

	return linearMap(data, NORMALIZED_EXTENT, extent, clamp);
	}

	/**
	* Convert coord to data. Data is the rank if it has an ordinal scale
	*/
	coordToData(coord: number, clamp?: boolean): number {
	let extent = this._extent;
	const scale = this.scale;

	if (this.onBand && scale.type === 'ordinal') {
	extent = extent.slice() as [number, number];
	fixExtentWithBands(extent, (scale as OrdinalScale).count());
	}

	const t = linearMap(coord, extent, NORMALIZED_EXTENT, clamp);

	return this.scale.scale(t);
	}

	/**
	* Convert pixel point to data in axis
	*/
	pointToData(point: number[], clamp?: boolean): number {
	// Should be implemented in derived class if necessary.
	return;
	}

	/**
	* Different from `zrUtil.map(axis.getTicks(), axis.dataToCoord, axis)`,
	* `axis.getTicksCoords` considers `onBand`, which is used by
	* `boundaryGap:true` of category axis and splitLine and splitArea.
	* @param opt.tickModel default: axis.model.getModel('axisTick')
	* @param opt.clamp If `true`, the first and the last
	* tick must be at the axis end points. Otherwise, clip ticks
	* that outside the axis extent.
	*/
	getTicksCoords(opt?: {
	tickModel?: Model,
	clamp?: boolean
	}): TickCoord[] {
	opt = opt \|\| {};

	const tickModel = opt.tickModel \|\| this.getTickModel();
	const result = createAxisTicks(this, tickModel as AxisBaseModel);
	const ticks = result.ticks;

	const ticksCoords = map(ticks, function (tickVal) {
	return {
	coord: this.dataToCoord(
	this.scale.type === 'ordinal'
	? (this.scale as OrdinalScale).getRawOrdinalNumber(tickVal)
	: tickVal
	),
	tickValue: tickVal
	};
	}, this);

	const alignWithLabel = tickModel.get('alignWithLabel');

	fixOnBandTicksCoords(
	this, ticksCoords, alignWithLabel, opt.clamp
	);

	return ticksCoords;
	}

	getMinorTicksCoords(): TickCoord[][] {
	if (this.scale.type === 'ordinal') {
	// Category axis doesn't support minor ticks
	return [];
	}

	const minorTickModel = this.model.getModel('minorTick');
	let splitNumber = minorTickModel.get('splitNumber');
	// Protection.
	if (!(splitNumber > 0 && splitNumber < 100)) {
	splitNumber = 5;
	}
	const minorTicks = this.scale.getMinorTicks(splitNumber);
	const minorTicksCoords = map(minorTicks, function (minorTicksGroup) {
	return map(minorTicksGroup, function (minorTick) {
	return {
	coord: this.dataToCoord(minorTick),
	tickValue: minorTick
	};
	}, this);
	}, this);
	return minorTicksCoords;
	}

	getViewLabels(): ReturnType<typeof createAxisLabels>['labels'] {
	return createAxisLabels(this).labels;
	}

	getLabelModel(): Model<AxisBaseOption['axisLabel']> {
	return this.model.getModel('axisLabel');
	}

	/**
	* Notice here we only get the default tick model. For splitLine
	* or splitArea, we should pass the splitLineModel or splitAreaModel
	* manually when calling `getTicksCoords`.
	* In GL, this method may be overrided to:
	* `axisModel.getModel('axisTick', grid3DModel.getModel('axisTick'));`
	*/
	getTickModel(): Model {
	return this.model.getModel('axisTick');
	}

	/**
	* Get width of band
	*/
	getBandWidth(): number {
	const axisExtent = this._extent;
	const dataExtent = this.scale.getExtent();

	let len = dataExtent[1] - dataExtent[0] + (this.onBand ? 1 : 0);
	// Fix #2728, avoid NaN when only one data.
	len === 0 && (len = 1);

	const size = Math.abs(axisExtent[1] - axisExtent[0]);

	return Math.abs(size) / len;
	}

	/**
	* Get axis rotate, by degree.
	*/
	getRotate: () => number;

	/**
	* Only be called in category axis.
	* Can be overrided, consider other axes like in 3D.
	* @return Auto interval for cateogry axis tick and label
	*/
	calculateCategoryInterval(): ReturnType<typeof calculateCategoryInterval> {
	return calculateCategoryInterval(this);
	}

	}

	function fixExtentWithBands(extent: [number, number], nTick: number): void {
	const size = extent[1] - extent[0];
	const len = nTick;
	const margin = size / len / 2;
	extent[0] += margin;
	extent[1] -= margin;
	}

	// If axis has labels [1, 2, 3, 4]. Bands on the axis are
	// \|---1---\|---2---\|---3---\|---4---\|.
	// So the displayed ticks and splitLine/splitArea should between
	// each data item, otherwise cause misleading (e.g., split tow bars
	// of a single data item when there are two bar series).
	// Also consider if tickCategoryInterval > 0 and onBand, ticks and
	// splitLine/spliteArea should layout appropriately corresponding
	// to displayed labels. (So we should not use `getBandWidth` in this
	// case).
	function fixOnBandTicksCoords(
	axis: Axis, ticksCoords: TickCoord[], alignWithLabel: boolean, clamp: boolean
	) {
	const ticksLen = ticksCoords.length;

	if (!axis.onBand \|\| alignWithLabel \|\| !ticksLen) {
	return;
	}

	const axisExtent = axis.getExtent();
	let last;
	let diffSize;
	if (ticksLen === 1) {
	ticksCoords[0].coord = axisExtent[0];
	last = ticksCoords[1] = {coord: axisExtent[0]};
	}
	else {
	const crossLen = ticksCoords[ticksLen - 1].tickValue - ticksCoords[0].tickValue;
	const shift = (ticksCoords[ticksLen - 1].coord - ticksCoords[0].coord) / crossLen;

	each(ticksCoords, function (ticksItem) {
	ticksItem.coord -= shift / 2;
	});

	const dataExtent = axis.scale.getExtent();
	diffSize = 1 + dataExtent[1] - ticksCoords[ticksLen - 1].tickValue;

	last = {coord: ticksCoords[ticksLen - 1].coord + shift * diffSize};

	ticksCoords.push(last);
	}

	const inverse = axisExtent[0] > axisExtent[1];

	// Handling clamp.
	if (littleThan(ticksCoords[0].coord, axisExtent[0])) {
	clamp ? (ticksCoords[0].coord = axisExtent[0]) : ticksCoords.shift();
	}
	if (clamp && littleThan(axisExtent[0], ticksCoords[0].coord)) {
	ticksCoords.unshift({coord: axisExtent[0]});
	}
	if (littleThan(axisExtent[1], last.coord)) {
	clamp ? (last.coord = axisExtent[1]) : ticksCoords.pop();
	}
	if (clamp && littleThan(last.coord, axisExtent[1])) {
	ticksCoords.push({coord: axisExtent[1]});
	}

	function littleThan(a: number, b: number): boolean {
	// Avoid rounding error cause calculated tick coord different with extent.
	// It may cause an extra unecessary tick added.
	a = round(a);
	b = round(b);
	return inverse ? a > b : a < b;
	}
	}

	export default Axis;