气泡测量第三步：魔棒flood fill，灰度阈值连通区域标记，空隙率实时计算

XP.ImageProcessing.RoiControl/Controls/PolygonRoiCanvas.xaml.cs

@@ -1183,12 +1183,131 @@ namespace XP.ImageProcessing.RoiControl.Controls
 
         private void ApplyBrushAt(Point pos)
         {
-            // 画笔/橡皮：暂时空实现，下一步实现
+            // 画笔/橡皮：下一步实现
         }
 
         private void UpdateBubbleResult()
         {
-            // 计算空隙率：暂时空实现，下一步实现
+            if (_bubbleMask == null || !_bubbleRoi.HasValue) return;
+            var roi = _bubbleRoi.Value;
+            int w = _bubbleMask.PixelWidth, h = _bubbleMask.PixelHeight;
+            int stride = w * 4;
+            var pixels = new byte[stride * h];
+            _bubbleMask.CopyPixels(pixels, stride, 0);
+
+            int roiX0 = Math.Max(0, (int)roi.X), roiY0 = Math.Max(0, (int)roi.Y);
+            int roiX1 = Math.Min(w, (int)roi.Right), roiY1 = Math.Min(h, (int)roi.Bottom);
+
+            int roiArea = 0, voidArea = 0;
+            for (int y = roiY0; y < roiY1; y++)
+                for (int x = roiX0; x < roiX1; x++)
+                {
+                    roiArea++;
+                    int idx = (y * w + x) * 4;
+                    if (pixels[idx + 3] > 0) voidArea++; // alpha > 0 表示已标记
+                }
+
+            double voidRate = roiArea > 0 ? voidArea * 100.0 / roiArea : 0;
+            RaiseMeasureCompleted(roi.TopLeft, roi.BottomRight, voidRate, 1, "BubbleVoid");
+        }
+
+        /// <summary>魔棒：在点击位置做 flood fill</summary>
+        public void WandFloodFill(Point pos)
+        {
+            if (_bubbleMask == null || !_bubbleRoi.HasValue || ImageSource == null) return;
+
+            var roi = _bubbleRoi.Value;
+            int px = (int)pos.X, py = (int)pos.Y;
+            if (!roi.Contains(pos)) return;
+
+            // 获取灰度像素
+            var gray = GetGrayscalePixels();
+            if (gray == null) return;
+
+            int w = _bubbleMask.PixelWidth, h = _bubbleMask.PixelHeight;
+            if (px < 0 || px >= w || py < 0 || py >= h) return;
+
+            int seedVal = gray[py * w + px];
+            int lo = _bubbleThreshold, hi = _bubbleThreshold;
+
+            // BFS flood fill
+            var visited = new bool[w * h];
+            var queue = new System.Collections.Generic.Queue<(int x, int y)>();
+            queue.Enqueue((px, py));
+            visited[py * w + px] = true;
+
+            int roiX0 = Math.Max(0, (int)roi.X), roiY0 = Math.Max(0, (int)roi.Y);
+            int roiX1 = Math.Min(w, (int)roi.Right), roiY1 = Math.Min(h, (int)roi.Bottom);
+
+            var filled = new System.Collections.Generic.List<(int x, int y)>();
+
+            while (queue.Count > 0)
+            {
+                var (cx, cy) = queue.Dequeue();
+                int val = gray[cy * w + cx];
+
+                // 阈值判断：与种子点灰度差在阈值范围内
+                if (Math.Abs(val - seedVal) > lo) continue;
+                // 必须在 ROI 内
+                if (cx < roiX0 || cx >= roiX1 || cy < roiY0 || cy >= roiY1) continue;
+
+                filled.Add((cx, cy));
+
+                // 四邻域
+                int[] dx = { -1, 1, 0, 0 }, dy = { 0, 0, -1, 1 };
+                for (int d = 0; d < 4; d++)
+                {
+                    int nx = cx + dx[d], ny = cy + dy[d];
+                    if (nx >= roiX0 && nx < roiX1 && ny >= roiY0 && ny < roiY1 && !visited[ny * w + nx])
+                    {
+                        visited[ny * w + nx] = true;
+                        queue.Enqueue((nx, ny));
+                    }
+                }
+            }
+
+            if (filled.Count == 0) return;
+
+            // 写入 mask（橙色半透明）
+            int stride = w * 4;
+            var maskPixels = new byte[stride * h];
+            _bubbleMask.CopyPixels(maskPixels, stride, 0);
+
+            foreach (var (fx, fy) in filled)
+            {
+                int idx = (fy * w + fx) * 4;
+                maskPixels[idx + 0] = 0;     // B
+                maskPixels[idx + 1] = 140;   // G
+                maskPixels[idx + 2] = 255;   // R (橙色)
+                maskPixels[idx + 3] = 180;   // A
+            }
+
+            _bubbleMask.WritePixels(new System.Windows.Int32Rect(0, 0, w, h), maskPixels, stride, 0);
+            UpdateBubbleResult();
+        }
+
+        /// <summary>从 ImageSource 提取灰度像素数组</summary>
+        private byte[] GetGrayscalePixels()
+        {
+            if (ImageSource is not BitmapSource bmp) return null;
+
+            int w = bmp.PixelWidth, h = bmp.PixelHeight;
+            if (w != (int)CanvasWidth || h != (int)CanvasHeight) return null;
+
+            // 转为 Bgra32
+            var converted = new FormatConvertedBitmap(bmp, PixelFormats.Bgra32, null, 0);
+            int stride = w * 4;
+            var pixels = new byte[stride * h];
+            converted.CopyPixels(pixels, stride, 0);
+
+            // 提取灰度
+            var gray = new byte[w * h];
+            for (int i = 0; i < w * h; i++)
+            {
+                int idx = i * 4;
+                gray[i] = (byte)(pixels[idx + 2] * 0.299 + pixels[idx + 1] * 0.587 + pixels[idx] * 0.114);
+            }
+            return gray;
         }
 
         /// <summary>清除气泡测量所有状态</summary>
@@ -1668,7 +1787,14 @@ namespace XP.ImageProcessing.RoiControl.Controls
             {
                 Point clickPosition = e.GetPosition(mainCanvas);
                 if (IsMeasuring)
+                {
                     HandleMeasureClick(clickPosition);
+                    // 魔棒点击
+                    if (CurrentMeasureMode == Models.MeasureMode.BubbleMeasure && _bubbleTool == BubbleSubTool.Wand && _bubbleRoi.HasValue)
+                    {
+                        WandFloodFill(clickPosition);
+                    }
+                }
                 OnCanvasClicked(clickPosition);
             }