fix undo (for previews), moving enums and helper methods to new classes, started adding current color lightness adjustment (mousewheel)

Author: unitycoder

PixelArtTool/BlendMode.cs

@@ -0,0 +1,9 @@
+namespace PixelArtTool
+{
+    public enum BlendMode : byte
+    {
+        Default = 0,
+        Additive = 1
+    }
+
+} // namespace

PixelArtTool/CustomPoint.cs

@@ -0,0 +1,16 @@
+using System.Runtime.InteropServices;
+using System.Windows;
+
+namespace PixelArtTool
+{
+    [StructLayout(LayoutKind.Sequential)]
+    public struct CustomPoint
+    {
+        public int X;
+        public int Y;
+        public static implicit operator Point(CustomPoint point)
+        {
+            return new Point(point.X, point.Y);
+        }
+    }
+} // namespace

PixelArtTool/EnumBooleanConverter.cs

@@ -0,0 +1,20 @@
+using System;
+using System.Windows.Data;
+
+namespace PixelArtTool
+{
+    // https://stackoverflow.com/a/2908885/5452781
+    public class EnumBooleanConverter : IValueConverter
+    {
+        public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
+        {
+            return value?.Equals(parameter);
+        }
+
+        public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
+        {
+            return value?.Equals(true) == true ? parameter : Binding.DoNothing;
+        }
+    }
+
+} // namespace

PixelArtTool/MainWindow.xaml

@@ -104,7 +104,7 @@
 			</ToolBar>
 
 			<ToolBar Band="1" BandIndex="1" VerticalAlignment="Top" Background="#FF9C9C9C">
-				<RadioButton GroupName="Toolbar" Tag="Draw" ToolTip="Brush (D)" Template="{DynamicResource ToggleButtonLeft}" Style="{StaticResource {x:Type ToggleButton}}"
+				<RadioButton GroupName="Toolbar" Tag="Draw" ToolTip="Brush (B)" Template="{DynamicResource ToggleButtonLeft}" Style="{StaticResource {x:Type ToggleButton}}"
 							 IsChecked="{Binding Path=CurrentTool, Converter={StaticResource ComparisonConverter}, ConverterParameter={x:Static local:ToolMode.Draw},Mode=TwoWay}">
 					<Image Source="/Resources/Buttons/drawmode.png" Width="24" Height="24" RenderOptions.BitmapScalingMode="NearestNeighbor" />
 				</RadioButton>