修复默认特效重复出现的问题

Greenshot/Drawing/Surface.cs

@@ -2045,6 +2045,8 @@ namespace Greenshot.Drawing
 		/// </summary>
 		public IDrawableContainerList Elements => _elements;
 
+        public bool HasDefaultEffect { get; set; } = false;
+
         /// <summary>
         /// pulls selected elements up one level in hierarchy
         /// </summary>

GreenshotPlugin/Core/AbstractDestination.cs

@@ -99,7 +99,11 @@ namespace GreenshotPlugin.Core {
                 return;
             }
             //set default border effect.
-            surface.ApplyBitmapEffect(new Effects.BorderEffect());
+            if (!surface.HasDefaultEffect)
+            {
+                surface.ApplyBitmapEffect(new Effects.DefaultEffect());
+                surface.HasDefaultEffect = true;
+            }
         }
 
 		public abstract ExportInformation ExportCapture(bool manuallyInitiated, ISurface surface, ICaptureDetails captureDetails);

GreenshotPlugin/Effects/DefaultEffect.cs

@@ -0,0 +1,40 @@
+using GreenshotPlugin.Core;
+using System.Drawing;
+using System.Drawing.Drawing2D;
+
+namespace GreenshotPlugin.Effects
+{
+    /// <summary>
+    /// default effect.
+    /// </summary>
+    public class DefaultEffect : IEffect
+    {
+        public DefaultEffect()
+        {
+            this.Reset();
+        }
+
+        public Color Color
+        {
+            get;
+            set;
+        }
+
+        public int Width
+        {
+            get;
+            set;
+        }
+
+        public Image Apply(Image sourceImage, Matrix matrix)
+        {
+            return ImageHelper.CreateBorder(sourceImage, Width, Color, sourceImage.PixelFormat, matrix);
+        }
+
+        public void Reset()
+        {
+            this.Width = 2;
+            this.Color = Color.Gray;
+        }
+    }
+}

GreenshotPlugin/GreenshotPlugin.csproj

@@ -50,6 +50,7 @@
     <Compile Include="Core\EventDelay.cs" />
     <Compile Include="Core\FastBitmap.cs" />
     <Compile Include="Core\Func.cs" />
+    <Compile Include="Effects\DefaultEffect.cs" />
     <Compile Include="Effects\GrayscaleEffect.cs" />
     <Compile Include="Effects\IEffect.cs" />
     <Compile Include="Core\IImage.cs" />

GreenshotPlugin/Interfaces/Generic.cs

@@ -263,5 +263,7 @@ namespace Greenshot.Plugin
 		int Height { get; }
 
 		void MakeUndoable(IMemento memento, bool allowMerge);
+
+        bool HasDefaultEffect { get; set; }
 	}
 }