feat: 重构generatePoints方法，使用Cesium的3D坐标系统计算圆周点

改进算法以考虑地球曲率，使用ENU局部坐标系

src/polygon/circle.ts

@@ -61,24 +61,86 @@ export default class Circle extends Base {
 
     const radius = Utils.MathDistance(center, pnt2);
 
-    const res = this.generatePoints(center, radius);
+    const res = this.generatePoints(positions);
     const temp = [].concat(...res);
     const cartesianPoints = this.cesium.Cartesian3.fromDegreesArray(temp);
     return cartesianPoints;
   }
-
-  generatePoints(center, radius) {
-    let x, y, angle;
+  generatePoints(positions) {
     const points = [];
+    const degreesPerRadian = 180.0 / Math.PI;
+
+    // 验证输入格式
+    if (!positions || positions.length !== 2) {
+      console.error('输入参数格式错误，需要包含两个世界坐标点');
+      return points;
+    }
+    // 提取中心点和第二点（均为Cartesian3世界坐标）
+    const centerCartesian = positions[0];
+    const secondPointCartesian = positions[1];
+
+    // 计算两点之间的距离作为半径（米）
+    const radius = this.cesium.Cartesian3.distance(centerCartesian, secondPointCartesian);
+    // 计算局部坐标系（东-北-上）
+    const localFrame = this.cesium.Transforms.eastNorthUpToFixedFrame(centerCartesian);
+    // 提取东向和北向单位向量
+    const eastVector = this.cesium.Cartesian3.fromElements(
+      localFrame[0],
+      localFrame[1],
+      localFrame[2],
+      new this.cesium.Cartesian3(),
+    );
+    const northVector = this.cesium.Cartesian3.fromElements(
+      localFrame[4],
+      localFrame[5],
+      localFrame[6],
+      new this.cesium.Cartesian3(),
+    );
+
+    // 归一化方向向量
+    this.cesium.Cartesian3.normalize(eastVector, eastVector);
+    this.cesium.Cartesian3.normalize(northVector, northVector);
+
+    // 生成圆周点
     for (let i = 0; i <= 100; i++) {
-      angle = (Math.PI * 2 * i) / 100;
-      x = center[0] + radius * Math.cos(angle);
-      y = center[1] + radius * Math.sin(angle);
-      points.push([x, y]);
+      const angle = (Math.PI * 2 * i) / 100;
+      const cosAngle = Math.cos(angle);
+      const sinAngle = Math.sin(angle);
+
+      // 计算偏移量（基于米）
+      const eastOffset = this.cesium.Cartesian3.multiplyByScalar(
+        eastVector,
+        radius * cosAngle,
+        new this.cesium.Cartesian3(),
+      );
+      const northOffset = this.cesium.Cartesian3.multiplyByScalar(
+        northVector,
+        radius * sinAngle,
+        new this.cesium.Cartesian3(),
+      );
+
+      // 计算目标点
+      const targetPoint = this.cesium.Cartesian3.add(
+        centerCartesian,
+        this.cesium.Cartesian3.add(eastOffset, northOffset, new this.cesium.Cartesian3()),
+        new this.cesium.Cartesian3(),
+      );
+
+      // 投影到椭球表面
+      const surfacePoint = this.cesium.Ellipsoid.WGS84.scaleToGeodeticSurface(
+        targetPoint,
+        new this.cesium.Cartesian3(),
+      );
+
+      // 转换回经纬度
+      const cartographic = this.cesium.Cartographic.fromCartesian(surfacePoint);
+      const longitude = cartographic.longitude * degreesPerRadian;
+      const latitude = cartographic.latitude * degreesPerRadian;
+
+      points.push([longitude, latitude]);
     }
     return points;
   }
-
   getPoints() {
     return this.points;
   }