feat(map-toolbar): 新增连续测距功能，支持多段测量并显示距离

src/components/map-toolbar.vue

@@ -76,6 +76,8 @@ const toggleMeasure = () => {
     start.value = null;
     end.value = null;
     current.value = null;
+    // 清理连续测距状态
+    try { mPts.value = []; mCur.value = null; } catch {}
   }
 };
 
@@ -133,6 +135,77 @@ onBeforeUnmount(() => {
   window.removeEventListener('keydown', onKeydown);
 });
 
+// =============== 连续测距（以米显示）增强 ===============
+// 独立的测距状态，连续点击可累加多段，双击结束
+const mPts = ref<Array<{ x: number; y: number }>>([]);
+const mCur = ref<{ x: number; y: number } | null>(null);
+
+const getScaleInfo = () => {
+  const editor = editorRef.value;
+  const canvasScale = editor?.store?.data?.scale ?? 1;
+  let mapScale = 1;
+  try {
+    const sceneJson = editor?.save?.();
+    if (sceneJson) {
+      const sceneData = JSON.parse(sceneJson as string);
+      if (typeof sceneData?.scale === 'number' && sceneData.scale > 0) {
+        mapScale = sceneData.scale;
+      }
+      // 如果场景scale与画布缩放一致且存在ratio，则以ratio作为地图自身缩放的回退
+      if (
+        typeof (sceneData as any)?.scale === 'number' &&
+        Math.abs((sceneData as any).scale - (canvasScale || 1)) < 1e-6 &&
+        typeof (sceneData as any)?.ratio === 'number' && (sceneData as any).ratio > 0
+      ) {
+        mapScale = (sceneData as any).ratio;
+      }
+    }
+  } catch {}
+  return { canvasScale, mapScale };
+};
+
+const totalPx2 = computed(() => {
+  // 仅在点击时（确认的点列）计算，不随鼠标移动而变化
+  if (!measuring.value) return 0;
+  let t = 0;
+  for (let i = 1; i < mPts.value.length; i++) {
+    const dx = mPts.value[i].x - mPts.value[i - 1].x;
+    const dy = mPts.value[i].y - mPts.value[i - 1].y;
+    t += Math.hypot(dx, dy);
+  }
+  return t;
+});
+
+const totalMeters2 = computed(() => {
+  const { canvasScale, mapScale } = getScaleInfo();
+  const denom = (canvasScale || 1) * (mapScale || 1);
+  if (denom <= 0) return 0;
+  return totalPx2.value / denom;
+});
+
+const distanceLabel2 = computed(() => {
+  const d = totalMeters2.value;
+  if (d >= 1000) return (d / 1000).toFixed(2) + ' km';
+  if (d >= 1) return d.toFixed(2) + ' m';
+  return (d * 100).toFixed(1) + ' cm';
+});
+
+const lastAnchor2 = computed(() => {
+  // 标签位置固定在最后一个确认点，避免鼠标移动触发变更
+  if (mPts.value.length) return mPts.value[mPts.value.length - 1];
+  return { x: 0, y: 0 };
+});
+
+const onMeasureDown = (e: MouseEvent) => {
+  if (!measuring.value) return;
+  mPts.value = [...mPts.value, { x: e.clientX, y: e.clientY }];
+};
+const onMeasureDblClick = () => {
+  measuring.value = false;
+  mPts.value = [];
+  mCur.value = null;
+};
+
 // 定义组件名称
 defineOptions({
   name: 'MapToolbar',
@@ -199,8 +272,8 @@ defineOptions({
   <div
     class="measure-overlay"
     :class="{ active: measuring }"
-    @mousedown="onMouseDownOverlay"
-    @mousemove="onMouseMoveOverlay"
+    @mousedown="onMeasureDown"
+    @dblclick="onMeasureDblClick"
   >
     <svg class="measure-svg" xmlns="http://www.w3.org/2000/svg">
       <g v-if="measuring && start && (end || current)">
@@ -230,6 +303,31 @@ defineOptions({
       <g v-else-if="measuring">
         <text x="20" y="40" fill="#fff" font-size="13">提示：依次点击两点进行测量，按 Esc 退出</text>
       </g>
+      <!-- 连续测距附加绘制（以米）：与上方原像素测距并存，仅在 measuring=true 时显示 -->
+      <g v-if="measuring">
+        <defs>
+          <marker id="arrow" markerWidth="6" markerHeight="6" refX="5" refY="3" orient="auto">
+            <path d="M0,0 L0,6 L6,3 z" fill="#1e90ff" />
+          </marker>
+        </defs>
+        <template v-if="mPts.length > 1">
+          <template v-for="(pt, idx) in mPts" :key="'seg2-'+idx">
+            <line v-if="idx > 0"
+              :x1="mPts[idx-1].x" :y1="mPts[idx-1].y"
+              :x2="pt.x" :y2="pt.y"
+              stroke="#1e90ff" stroke-width="2" />
+          </template>
+        </template>
+        
+        <template v-for="(pt, idx) in mPts" :key="'dot2-'+idx">
+          <circle :cx="pt.x" :cy="pt.y" r="4" fill="#1e90ff" />
+        </template>
+        
+        <g :transform="`translate(${lastAnchor2.x}, ${lastAnchor2.y - 16})`">
+          <rect x="-60" y="-18" width="120" height="20" rx="4" ry="4" fill="rgba(0,0,0,0.6)" />
+          <text x="0" y="-4" fill="#fff" font-size="12" text-anchor="middle">{{ distanceLabel2 }}</text>
+        </g>
+      </g>
     </svg>
   </div>
 </template>