设计了流程接口节点，能够切换本节点数据、目标节点数据，目前还有数据来源相关操作没有实现

Workbench/Converters/ThumbPositionConverter.cs

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+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using System.Windows.Data;
+
+namespace Serein.Workbench.Converters
+{
+    /// <summary>
+    /// 画布拉动范围距离计算器
+    /// </summary>
+    public class RightThumbPositionConverter : IValueConverter
+    {
+        public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
+        {
+            if (value is double width)
+                return width - 10; // Adjust for Thumb width
+            return 0;
+        }
+
+        public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
+        {
+            throw new NotImplementedException();
+        }
+    }
+    /// <summary>
+    /// 画布拉动范围距离计算器
+    /// </summary>
+    public class BottomThumbPositionConverter : IValueConverter
+    {
+        public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
+        {
+            if (value is double height)
+                return height - 10; // Adjust for Thumb height
+            return 0;
+        }
+
+        public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
+        {
+            throw new NotImplementedException();
+        }
+    }
+    /// <summary>
+    /// 画布拉动范围距离计算器
+    /// </summary>
+    public class VerticalCenterThumbPositionConverter : IValueConverter
+    {
+        public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
+        {
+            if (value is double height)
+                return height / 2 - 5; // Centering Thumb vertically
+            return 0;
+        }
+
+        public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
+        {
+            throw new NotImplementedException();
+        }
+    }
+    /// <summary>
+    /// 画布拉动范围距离计算器
+    /// </summary>
+    public class HorizontalCenterThumbPositionConverter : IValueConverter
+    {
+        public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
+        {
+            if (value is double width)
+                return width / 2 - 5; // Centering Thumb horizontally
+            return 0;
+        }
+
+        public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
+        {
+            throw new NotImplementedException();
+        }
+    }
+
+}