zh/builder/src/echarts/util/shape/sausage.js

/*
* 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 { extendShape } from '../graphic';
/**
 * Sausage: similar to sector, but have half circle on both sides
 * @public
 */

export default extendShape({
  type: 'sausage',
  shape: {
    cx: 0,
    cy: 0,
    r0: 0,
    r: 0,
    startAngle: 0,
    endAngle: Math.PI * 2,
    clockwise: true
  },
  buildPath: function (ctx, shape) {
    var x = shape.cx;
    var y = shape.cy;
    var r0 = Math.max(shape.r0 || 0, 0);
    var r = Math.max(shape.r, 0);
    var dr = (r - r0) * 0.5;
    var rCenter = r0 + dr;
    var startAngle = shape.startAngle;
    var endAngle = shape.endAngle;
    var clockwise = shape.clockwise;
    var unitStartX = Math.cos(startAngle);
    var unitStartY = Math.sin(startAngle);
    var unitEndX = Math.cos(endAngle);
    var unitEndY = Math.sin(endAngle);
    var lessThanCircle = clockwise ? endAngle - startAngle < Math.PI * 2 : startAngle - endAngle < Math.PI * 2;

    if (lessThanCircle) {
      ctx.moveTo(unitStartX * r0 + x, unitStartY * r0 + y);
      ctx.arc(unitStartX * rCenter + x, unitStartY * rCenter + y, dr, -Math.PI + startAngle, startAngle, !clockwise);
    }

    ctx.arc(x, y, r, startAngle, endAngle, !clockwise);
    ctx.moveTo(unitEndX * r + x, unitEndY * r + y);
    ctx.arc(unitEndX * rCenter + x, unitEndY * rCenter + y, dr, endAngle - Math.PI * 2, endAngle - Math.PI, !clockwise);

    if (r0 !== 0) {
      ctx.arc(x, y, r0, endAngle, startAngle, clockwise);
      ctx.moveTo(unitStartX * r0 + x, unitEndY * r0 + y);
    }

    ctx.closePath();
  }
});