气泡测量：画笔涂抹标记、橡皮擦清除、ROI外可正常拖动图像

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

@@ -386,6 +386,7 @@ namespace XP.ImageProcessing.RoiControl.Controls
         private int _bubbleThreshold = 128;
         private int _bubbleBrushSize = 5;
         private bool _bubbleBrushDragging;
+        private readonly System.Collections.Generic.Stack<byte[]> _bubbleUndoStack = new();
 
         public void SetBubbleTool(BubbleSubTool tool) => _bubbleTool = tool;
         public void SetBubbleThreshold(int val) => _bubbleThreshold = val;
@@ -1183,7 +1184,54 @@ namespace XP.ImageProcessing.RoiControl.Controls
 
         private void ApplyBrushAt(Point pos)
         {
-            // 画笔/橡皮：下一步实现
+            if (_bubbleMask == null || !_bubbleRoi.HasValue) return;
+
+            var roi = _bubbleRoi.Value;
+            int w = _bubbleMask.PixelWidth, h = _bubbleMask.PixelHeight;
+            int cx = (int)pos.X, cy = (int)pos.Y;
+            int r = _bubbleBrushSize;
+            bool erase = _bubbleTool == BubbleSubTool.Eraser;
+
+            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);
+
+            // 计算笔刷影响的矩形区域
+            int x0 = Math.Max(roiX0, cx - r), y0 = Math.Max(roiY0, cy - r);
+            int x1 = Math.Min(roiX1, cx + r + 1), y1 = Math.Min(roiY1, cy + r + 1);
+            if (x0 >= x1 || y0 >= y1) return;
+
+            int regionW = x1 - x0, regionH = y1 - y0;
+            int stride = w * 4;
+
+            // 读取整行范围的像素
+            var pixels = new byte[regionW * regionH * 4];
+            _bubbleMask.CopyPixels(new System.Windows.Int32Rect(x0, y0, regionW, regionH), pixels, regionW * 4, 0);
+
+            int r2 = r * r;
+            for (int py2 = y0; py2 < y1; py2++)
+            {
+                for (int px2 = x0; px2 < x1; px2++)
+                {
+                    int dx = px2 - cx, dy = py2 - cy;
+                    if (dx * dx + dy * dy > r2) continue;
+
+                    int idx = ((py2 - y0) * regionW + (px2 - x0)) * 4;
+                    if (erase)
+                    {
+                        pixels[idx + 0] = 0; pixels[idx + 1] = 0;
+                        pixels[idx + 2] = 0; pixels[idx + 3] = 0;
+                    }
+                    else
+                    {
+                        pixels[idx + 0] = 0;     // B
+                        pixels[idx + 1] = 140;   // G
+                        pixels[idx + 2] = 255;   // R
+                        pixels[idx + 3] = 180;   // A
+                    }
+                }
+            }
+
+            _bubbleMask.WritePixels(new System.Windows.Int32Rect(x0, y0, regionW, regionH), pixels, regionW * 4, 0);
         }
 
         private void UpdateBubbleResult()
@@ -1216,6 +1264,9 @@ namespace XP.ImageProcessing.RoiControl.Controls
         {
             if (_bubbleMask == null || !_bubbleRoi.HasValue || ImageSource == null) return;
 
+            // 保存快照用于撤销
+            SaveMaskSnapshot();
+
             var roi = _bubbleRoi.Value;
             int px = (int)pos.X, py = (int)pos.Y;
             if (!roi.Contains(pos)) return;
@@ -1310,6 +1361,26 @@ namespace XP.ImageProcessing.RoiControl.Controls
             return gray;
         }
 
+        private void SaveMaskSnapshot()
+        {
+            if (_bubbleMask == null) return;
+            int w = _bubbleMask.PixelWidth, h = _bubbleMask.PixelHeight;
+            int stride = w * 4;
+            var snapshot = new byte[stride * h];
+            _bubbleMask.CopyPixels(snapshot, stride, 0);
+            _bubbleUndoStack.Push(snapshot);
+        }
+
+        /// <summary>撤销上一次魔棒/画笔操作</summary>
+        public void UndoBubble()
+        {
+            if (_bubbleMask == null || _bubbleUndoStack.Count == 0) return;
+            var snapshot = _bubbleUndoStack.Pop();
+            int w = _bubbleMask.PixelWidth, h = _bubbleMask.PixelHeight;
+            _bubbleMask.WritePixels(new System.Windows.Int32Rect(0, 0, w, h), snapshot, w * 4, 0);
+            UpdateBubbleResult();
+        }
+
         /// <summary>清除气泡测量所有状态</summary>
         public void ClearBubbleMeasure()
         {
@@ -1327,6 +1398,7 @@ namespace XP.ImageProcessing.RoiControl.Controls
             _bubbleRoiResizing = false;
             _bubbleBrushDragging = false;
             _bubbleTool = BubbleSubTool.Roi;
+            _bubbleUndoStack.Clear();
         }
 
         // 气泡工具切换事件
@@ -1657,11 +1729,16 @@ namespace XP.ImageProcessing.RoiControl.Controls
                 }
                 if ((_bubbleTool == BubbleSubTool.Brush || _bubbleTool == BubbleSubTool.Eraser) && _bubbleRoi.HasValue)
                 {
-                    _bubbleBrushDragging = true;
-                    ApplyBrushAt(pos);
-                    mainCanvas.CaptureMouse();
-                    e.Handled = true;
-                    return;
+                    // 只在 ROI 内才启动画笔，ROI 外不拦截，让图像正常拖动
+                    if (_bubbleRoi.Value.Contains(pos))
+                    {
+                        SaveMaskSnapshot();
+                        _bubbleBrushDragging = true;
+                        ApplyBrushAt(pos);
+                        mainCanvas.CaptureMouse();
+                        e.Handled = true;
+                        return;
+                    }
                 }
                 // 魔棒在 MouseUp（CanvasClicked）中处理
             }