utils增加均分折线

src/jlgraphic/utils/GraphicUtils.ts

@@ -695,6 +695,42 @@ export function splitLineEvenly(
     });
 }
 
+export function splitPolyline(points: IPointData[], count: number) {
+  if (points.length !== 2) {
+    let totalLen = 0;
+    const lengths: number[] = [];
+    for (let i = 1; i < points.length; i++) {
+      const { x: x1, y: y1 } = points[i - 1],
+        { x: x2, y: y2 } = points[i];
+      const len = new Vector2([x2 - x1, y2 - y1]).length();
+      totalLen += len;
+      lengths.push(len);
+    }
+    const counts = lengths.map((length) =>
+      Math.round((count * length) / totalLen)
+    );
+    if (counts.reduce((p, c) => p + c, 0) !== count) {
+      const intersection = counts.reduce((p, c) => p + c, 0) - count;
+      let maxCountIndex = 0,
+        maxCount = 0;
+      counts.forEach((c, i) => {
+        if (c > maxCount) {
+          maxCount = c;
+          maxCountIndex = i;
+        }
+      });
+      counts[maxCountIndex] + intersection;
+    }
+    return counts
+      .map((count, i) => {
+        return splitLineEvenly(points[i], points[i + 1], count);
+      })
+      .flat();
+  } else {
+    return splitLineEvenly(points[0], points[points.length - 1], count);
+  }
+}
+
 export function getParallelOfPolyline(
   points: IPointData[],
   offset: number,