使用像素尺寸，避免DPI不同导致DIP尺寸与实际像素不一致

XP.ImageProcessing.RoiControl/Controls/PolygonRoiCanvas.xaml

@@ -17,28 +17,20 @@
     </UserControl.Resources>
     <Border BorderBrush="Transparent" BorderThickness="1" ClipToBounds="True">
         <Grid>
-            <!-- 图像显示区域（去掉左侧按钮列，全部空间给图像） -->
+            <!-- 图像显示区域 -->
             <Grid x:Name="imageDisplayGrid" ClipToBounds="True">
-                <Grid.ContextMenu>
-                    <ContextMenu>
-                        <MenuItem Header="放大" Click="BtnZoomIn_Click" />
-                        <MenuItem Header="缩小" Click="BtnZoomOut_Click" />
-                        <MenuItem Header="适应窗口" Click="BtnReset_Click" />
-                    </ContextMenu>
-                </Grid.ContextMenu>
                 <Grid x:Name="transformGrid"
-                      RenderTransformOrigin="0.5,0.5"
                       HorizontalAlignment="Center"
                       VerticalAlignment="Center">
-                    <Grid.RenderTransform>
-                        <TransformGroup>
+                    <Grid.LayoutTransform>
                         <ScaleTransform x:Name="scaleTransform"
                                         ScaleX="{Binding ZoomScale, ElementName=root}"
                                         ScaleY="{Binding ZoomScale, ElementName=root}" />
+                    </Grid.LayoutTransform>
+                    <Grid.RenderTransform>
                         <TranslateTransform x:Name="translateTransform"
                                             X="{Binding PanOffsetX, ElementName=root}"
                                             Y="{Binding PanOffsetY, ElementName=root}" />
-                        </TransformGroup>
                     </Grid.RenderTransform>
 
                     <Canvas x:Name="mainCanvas"

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

@@ -7,6 +7,7 @@ using System.Windows.Controls;
 using System.Windows.Documents;
 using System.Windows.Input;
 using System.Windows.Media;
+using System.Windows.Media.Imaging;
 using System.Windows.Shapes;
 
 namespace XP.ImageProcessing.RoiControl.Controls
@@ -120,11 +121,17 @@ namespace XP.ImageProcessing.RoiControl.Controls
         private static void OnImageSourceChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
         {
             var control = (PolygonRoiCanvas)d;
-            if (e.NewValue is ImageSource imageSource)
+            if (e.NewValue is BitmapSource bitmap)
+            {
+                // 使用像素尺寸，避免 DPI 不同导致 DIP 尺寸与实际像素不一致
+                control.CanvasWidth = bitmap.PixelWidth;
+                control.CanvasHeight = bitmap.PixelHeight;
+                control.ResetView();
+            }
+            else if (e.NewValue is ImageSource imageSource)
             {
                 control.CanvasWidth = imageSource.Width;
                 control.CanvasHeight = imageSource.Height;
-                // 图像加载后自动适应窗口居中显示
                 control.ResetView();
             }
         }
@@ -411,35 +418,33 @@ namespace XP.ImageProcessing.RoiControl.Controls
 
         public void ResetView()
         {
-            // 自动适应显示窗口 (类似 PictureBox SizeMode.Zoom)
-            ZoomScale = 1.0;
             PanOffsetX = 0;
             PanOffsetY = 0;
 
-            if (imageDisplayGrid != null && CanvasWidth > 0 && CanvasHeight > 0)
+            if (imageDisplayGrid == null || CanvasWidth <= 0 || CanvasHeight <= 0)
             {
-                // 使用 Dispatcher 延迟执行，确保布局已完成
+                ZoomScale = 1.0;
+                return;
+            }
+
+            // 延迟到布局完成后计算，确保 ActualWidth/Height 准确
             Dispatcher.BeginInvoke(new Action(() =>
             {
-                    // 获取图像显示区域的实际尺寸
-                    double viewportWidth = imageDisplayGrid.ActualWidth;
-                    double viewportHeight = imageDisplayGrid.ActualHeight;
+                double viewW = imageDisplayGrid.ActualWidth;
+                double viewH = imageDisplayGrid.ActualHeight;
 
-                    if (viewportWidth > 0 && viewportHeight > 0)
+                if (viewW > 0 && viewH > 0)
                 {
-                        // 计算宽度和高度的缩放比例
-                        double scaleX = viewportWidth / CanvasWidth;
-                        double scaleY = viewportHeight / CanvasHeight;
+                    ZoomScale = Math.Min(viewW / CanvasWidth, viewH / CanvasHeight);
+                }
+                else
+                {
+                    ZoomScale = 1.0;
+                }
 
-                        // 选择较小的缩放比例，确保图像完全显示在窗口内（保持宽高比）
-                        ZoomScale = Math.Min(scaleX, scaleY);
-
-                        // 居中显示由 Grid 的 HorizontalAlignment 和 VerticalAlignment 自动处理
                 PanOffsetX = 0;
                 PanOffsetY = 0;
-                    }
-                }), System.Windows.Threading.DispatcherPriority.Loaded);
-            }
+            }), System.Windows.Threading.DispatcherPriority.Render);
         }
 
         private void BtnZoomIn_Click(object sender, RoutedEventArgs e)