From 55dff063802e49b71ddf2f22d53a7fb9cc0bc4cb Mon Sep 17 00:00:00 2001
From: Darth Affe <darthaffe@wyrez.org>
Date: Thu, 22 Dec 2016 12:03:38 +0100
Subject: [PATCH] Implemented Gradient-Wrapping

---
 Gradients/AbstractGradient.cs | 22 +++++++++++++++++++++
 Gradients/LinearGradient.cs   | 37 ++++++++++++++++++++++++++++++++---
 2 files changed, 56 insertions(+), 3 deletions(-)

diff --git a/Gradients/AbstractGradient.cs b/Gradients/AbstractGradient.cs
index c6ea39c..c399a80 100644
--- a/Gradients/AbstractGradient.cs
+++ b/Gradients/AbstractGradient.cs
@@ -1,4 +1,6 @@
 // ReSharper disable MemberCanBeProtected.Global
+// ReSharper disable MemberCanBePrivate.Global
+// ReSharper disable AutoPropertyCanBeMadeGetOnly.Global
 
 using System.Collections.Generic;
 using System.Linq;
@@ -18,6 +20,13 @@ namespace CUE.NET.Gradients
         /// </summary>
         public IList<GradientStop> GradientStops { get; } = new List<GradientStop>();
 
+        /// <summary>
+        /// Gets or sets if the Gradient wraps around if there isn't a second stop to take.
+        /// Example: There is a stop at offset 0f, 0.5f and 0.75f. 
+        /// Without wrapping offset 1f will be calculated the same as 0.75f. With wrapping it would be the same as 0f.
+        /// </summary>
+        public bool WrapGradient { get; set; }
+
         #endregion
 
         #region Constructors
@@ -38,6 +47,19 @@ namespace CUE.NET.Gradients
                 GradientStops.Add(gradientStop);
         }
 
+        /// <summary>
+        /// Initializes a new instance of the <see cref="AbstractGradient"/> class.
+        /// </summary>
+        /// <param name="wrapGradient">Specifies whether the gradient should wrapp or not (see <see cref="WrapGradient"/> for an example of what this means).</param>
+        /// <param name="gradientStops">The stops with which the gradient should be initialized.</param>
+        protected AbstractGradient(bool wrapGradient, params GradientStop[] gradientStops)
+        {
+            this.WrapGradient = wrapGradient;
+
+            foreach (GradientStop gradientStop in gradientStops)
+                GradientStops.Add(gradientStop);
+        }
+
         #endregion
 
         #region Methods
diff --git a/Gradients/LinearGradient.cs b/Gradients/LinearGradient.cs
index 7f6a540..49333db 100644
--- a/Gradients/LinearGradient.cs
+++ b/Gradients/LinearGradient.cs
@@ -26,6 +26,15 @@ namespace CUE.NET.Gradients
             : base(gradientStops)
         { }
 
+        /// <summary>
+        /// Initializes a new instance of the <see cref="AbstractGradient"/> class.
+        /// </summary>
+        /// <param name="wrapGradient">Specifies whether the gradient should wrapp or not (see <see cref="AbstractGradient.WrapGradient"/> for an example of what this means).</param>
+        /// <param name="gradientStops">The stops with which the gradient should be initialized.</param>
+        public LinearGradient(bool wrapGradient, params GradientStop[] gradientStops)
+            : base(wrapGradient, gradientStops)
+        { }
+
         #endregion
 
         #region Methods
@@ -40,10 +49,32 @@ namespace CUE.NET.Gradients
             if (!GradientStops.Any()) return CorsairColor.Transparent;
             if (GradientStops.Count == 1) return GradientStops.First().Color;
 
-            offset = ClipOffset(offset);
+            GradientStop gsBefore;
+            GradientStop gsAfter;
 
-            GradientStop gsBefore = GradientStops.Where(n => n.Offset <= offset).OrderBy(n => n.Offset).Last();
-            GradientStop gsAfter = GradientStops.Where(n => n.Offset >= offset).OrderBy(n => n.Offset).First();
+            if (WrapGradient)
+            {
+                gsBefore = GradientStops.Where(n => n.Offset <= offset).OrderBy(n => n.Offset).LastOrDefault();
+                if (gsBefore == null)
+                {
+                    GradientStop lastStop = GradientStops.OrderBy(n => n.Offset).Last();
+                    gsBefore = new GradientStop(lastStop.Offset - 1f, lastStop.Color);
+                }
+
+                gsAfter = GradientStops.Where(n => n.Offset >= offset).OrderBy(n => n.Offset).FirstOrDefault();
+                if (gsAfter == null)
+                {
+                    GradientStop firstStop = GradientStops.OrderBy(n => n.Offset).First();
+                    gsAfter = new GradientStop(firstStop.Offset + 1f, firstStop.Color);
+                }
+            }
+            else
+            {
+                offset = ClipOffset(offset);
+
+                gsBefore = GradientStops.Where(n => n.Offset <= offset).OrderBy(n => n.Offset).Last();
+                gsAfter = GradientStops.Where(n => n.Offset >= offset).OrderBy(n => n.Offset).First();
+            }
 
             float blendFactor = 0f;
             if (!gsBefore.Offset.Equals(gsAfter.Offset))