add polygon

examples/index.ts

@@ -66,6 +66,9 @@ const buttonGroup = document.getElementById('button-group') as HTMLElement;
 buttonGroup.onclick = (evt) => {
   const targetElement = evt.target as HTMLElement;
   switch (targetElement.id) {
+    case 'drawPolygon':
+      geometry = new CesiumPlot.Polygon(Cesium, viewer);
+      break;
     case 'drawReactangle':
       geometry = new CesiumPlot.Reactangle(Cesium, viewer);
       break;

index.html

@@ -45,6 +45,7 @@
     <div id="root"></div>
     <div id="cesiumContainer"></div>
     <div class="button-container" id="button-group">
+      <button id="drawPolygon">多边形</button>
       <button id="drawReactangle">矩形</button>
       <button id="drawTriangle">三角形</button>
       <button id="drawStraightArrow">细直箭头</button>

src/index.ts

@@ -14,6 +14,7 @@ import Ellipse from './polygon/ellipse';
 import Lune from './polygon/lune';
 import Reactangle from './polygon/rectangle';
 import Triangle from './polygon/triangle';
+import Polygon from './polygon/polygon';
 
 const CesiumPlot = {
   FineArrow,
@@ -31,7 +32,8 @@ const CesiumPlot = {
   Ellipse,
   Lune,
   Reactangle,
-  Triangle
+  Triangle,
+  Polygon,
 };
 
 export default CesiumPlot;

src/polygon/polygon.ts

@@ -0,0 +1,56 @@
+import Base from '../base';
+// @ts-ignore
+import { Cartesian3 } from '@examples/cesium';
+
+import { PolygonStyle } from '../interface';
+
+export default class Polygon extends Base {
+  points: Cartesian3[] = [];
+
+  constructor(cesium: any, viewer: any, style?: PolygonStyle) {
+    super(cesium, viewer, style);
+    this.cesium = cesium;
+    this.setState('drawing');
+    this.onDoubleClick();
+  }
+
+  getType(): 'polygon' | 'line' {
+    return 'polygon';
+  }
+
+  /**
+   * Add points only on click events
+   */
+  addPoint(cartesian: Cartesian3) {
+    this.points.push(cartesian);
+    if (this.points.length === 1) {
+      this.onMouseMove();
+    } 
+  }
+
+  /**
+   * Draw a shape based on mouse movement points during the initial drawing.
+   */
+  updateMovingPoint(cartesian: Cartesian3) {
+    const tempPoints = [...this.points, cartesian];
+    this.setGeometryPoints(tempPoints);
+    if (tempPoints.length === 2) {
+      this.addFirstLineOfTheArrow();
+    } else {
+      this.drawPolygon();
+    }
+  }
+
+  /**
+   * In edit mode, drag key points to update corresponding key point data.
+   */
+  updateDraggingPoint(cartesian: Cartesian3, index: number) {
+    this.points[index] = cartesian;
+    this.setGeometryPoints(this.points);
+    this.drawPolygon();
+  }
+
+  getPoints() {
+    return this.points;
+  }
+}