Initial implementation

RGBSync+/Converter/BoolToVisibilityConverter.cs

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+using System;
+using System.Globalization;
+using System.Windows;
+using System.Windows.Data;
+
+namespace RGBSyncPlus.Converter
+{
+    [ValueConversion(typeof(bool), typeof(Visibility))]
+    public class BoolToVisibilityConverter : IValueConverter
+    {
+        #region Methods
+
+        public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
+            => (value as bool?) == true ? Visibility.Visible
+            : (string.Equals(parameter?.ToString(), "true", StringComparison.OrdinalIgnoreCase) ? Visibility.Hidden : Visibility.Collapsed);
+
+        public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture) => value as Visibility? == Visibility.Visible;
+
+        #endregion
+    }
+}

RGBSync+/Converter/EqualsToBoolConverter.cs

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+using System;
+using System.Globalization;
+using System.Windows.Data;
+
+namespace RGBSyncPlus.Converter
+{
+    [ValueConversion(typeof(object), typeof(bool))]
+    public class EqualsToBoolConverter : IValueConverter
+    {
+        #region Methods
+
+        public object Convert(object value, Type targetType, object parameter, CultureInfo culture) => Equals(value, parameter);
+
+        public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture) => throw new NotSupportedException();
+
+        #endregion
+    }
+}

RGBSync+/Converter/NullToVisibilityConverter.cs

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+using System;
+using System.Globalization;
+using System.Windows;
+using System.Windows.Data;
+
+namespace RGBSyncPlus.Converter
+{
+    [ValueConversion(typeof(object), typeof(Visibility))]
+    public class NullToVisibilityConverter : IValueConverter
+    {
+        #region Methods
+
+        public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
+            => (value == null) == (string.Equals(parameter?.ToString(), "true", StringComparison.OrdinalIgnoreCase)) ? Visibility.Visible : Visibility.Hidden;
+
+        public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture) => throw new NotSupportedException();
+
+        #endregion
+    }
+}

RGBSync+/Converter/ScrollOffsetToOpacityMaskConverter.cs

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+using System;
+using System.Globalization;
+using System.Windows;
+using System.Windows.Data;
+using System.Windows.Media;
+
+namespace RGBSyncPlus.Converter
+{
+    public class ScrollOffsetToOpacityMaskConverter : IMultiValueConverter
+    {
+        #region Constants
+
+        private static readonly Color TRANSPARENT = Color.FromArgb(0, 0, 0, 0);
+        private static readonly Color OPAQUE = Color.FromArgb(255, 0, 0, 0);
+
+        #endregion
+
+        #region Methods
+
+        public object Convert(object[] values, Type targetType, object parameter, CultureInfo culture)
+        {
+            double offset = double.Parse(values[0].ToString());
+            double maxHeight = double.Parse(values[1].ToString());
+            double height = double.Parse(values[2].ToString());
+
+            double transparencyHeight = double.Parse(parameter.ToString());
+            double transparencyFactor = (transparencyHeight - 6) / height;
+            double transparencyFadeFactor = (transparencyHeight + 4) / height;
+
+            bool top = !(Math.Abs(offset) < float.Epsilon);
+            bool bot = !(Math.Abs(offset - maxHeight) < float.Epsilon);
+
+            if (!top && !bot) return new SolidColorBrush(OPAQUE);
+
+            GradientStopCollection gradientStops = new GradientStopCollection();
+            if (top)
+            {
+                gradientStops.Add(new GradientStop(TRANSPARENT, 0.0));
+                gradientStops.Add(new GradientStop(TRANSPARENT, transparencyFactor));
+                gradientStops.Add(new GradientStop(OPAQUE, transparencyFadeFactor));
+            }
+            else
+                gradientStops.Add(new GradientStop(OPAQUE, 0.0));
+
+            if (bot)
+            {
+                gradientStops.Add(new GradientStop(OPAQUE, 1.0 - transparencyFadeFactor));
+                gradientStops.Add(new GradientStop(TRANSPARENT, 1.0 - transparencyFactor));
+                gradientStops.Add(new GradientStop(TRANSPARENT, 1.0));
+            }
+            else
+                gradientStops.Add(new GradientStop(OPAQUE, 1.0));
+
+            return new LinearGradientBrush(gradientStops, new Point(0.5, 0.0), new Point(0.5, 1.0));
+        }
+
+        public object[] ConvertBack(object value, Type[] targetTypes, object parameter, CultureInfo culture) => throw new NotSupportedException();
+
+        #endregion
+    }
+}

RGBSync+/Converter/ScrollOffsetToVisibilityConverter.cs

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+using System;
+using System.Globalization;
+using System.Windows;
+using System.Windows.Data;
+
+namespace RGBSyncPlus.Converter
+{
+    // Based on: http://stackoverflow.com/a/28679767
+    public class ScrollOffsetToVisibilityConverter : IMultiValueConverter
+    {
+        #region Methods
+
+        public object Convert(object[] values, Type targetType, object parameter, CultureInfo culture)
+        {
+            bool top = "top".Equals(parameter?.ToString(), StringComparison.OrdinalIgnoreCase);
+
+            double offset = double.Parse(values[0].ToString());
+            double maxHeight = double.Parse(values[1].ToString());
+
+            return (top && Math.Abs(offset) < float.Epsilon) || (!top && Math.Abs(offset - maxHeight) < float.Epsilon)
+                ? Visibility.Collapsed
+                : Visibility.Visible;
+        }
+
+        public object[] ConvertBack(object value, Type[] targetTypes, object parameter, CultureInfo culture) => throw new NotSupportedException();
+
+        #endregion
+    }
+}