Added unit tests to test copying to and from ZYX and ZYXW.

tests/ImageSharp.Tests/PixelAccessorTests.cs

@@ -0,0 +1,168 @@
+// <copyright file="PixelAccessorTests.cs" company="James Jackson-South">
+// Copyright (c) James Jackson-South and contributors.
+// Licensed under the Apache License, Version 2.0.
+// </copyright>
+
+namespace ImageSharp.Tests
+{
+    using Xunit;
+
+    /// <summary>
+    /// Tests the <see cref="PixelAccessor"/> class.
+    /// </summary>
+    public class PixelAccessorTests
+    {
+        [Fact]
+        public void CopyFromZYX()
+        {
+            CopyFromZYX(new Image<Color, uint>(1, 1));
+        }
+
+        [Fact]
+        public void CopyFromZYXOptimized()
+        {
+            CopyFromZYX(new Image(1, 1));
+        }
+
+        [Fact]
+        public void CopyFromZYXW()
+        {
+            CopyFromZYXW(new Image<Color, uint>(1, 1));
+        }
+
+        [Fact]
+        public void CopyFromZYXWOptimized()
+        {
+            CopyFromZYXW(new Image(1, 1));
+        }
+
+        [Fact]
+        public void CopyToZYX()
+        {
+            CopyToZYX(new Image<Color, uint>(1, 1));
+        }
+
+        [Fact]
+        public void CopyToZYXOptimized()
+        {
+            CopyToZYX(new Image(1, 1));
+        }
+
+        [Fact]
+        public void CopyToZYXW()
+        {
+            CopyToZYXW(new Image<Color, uint>(1, 1));
+        }
+
+        [Fact]
+        public void CopyToZYXWOptimized()
+        {
+            CopyToZYXW(new Image(1, 1));
+        }
+
+        private static void CopyFromZYX<TColor, TPacked>(Image<TColor, TPacked> image)
+            where TColor : struct, IPackedPixel<TPacked>
+        where TPacked : struct
+        {
+            using (PixelAccessor<TColor, TPacked> pixels = image.Lock())
+            {
+                byte red = 1;
+                byte green = 2;
+                byte blue = 3;
+                byte alpha = 255;
+
+                using (PixelRow<TColor, TPacked> row = new PixelRow<TColor, TPacked>(1, ComponentOrder.ZYX))
+                {
+                    row.Bytes[0] = blue;
+                    row.Bytes[1] = green;
+                    row.Bytes[2] = red;
+
+                    pixels.CopyFrom(row, 0);
+
+                    Color color = (Color) (object) pixels[0, 0];
+                    Assert.Equal(red, color.R);
+                    Assert.Equal(green, color.G);
+                    Assert.Equal(blue, color.B);
+                    Assert.Equal(alpha, color.A);
+                }
+            }
+        }
+
+        private static void CopyFromZYXW<TColor, TPacked>(Image<TColor, TPacked> image)
+            where TColor : struct, IPackedPixel<TPacked>
+        where TPacked : struct
+        {
+            using (PixelAccessor<TColor, TPacked> pixels = image.Lock())
+            {
+                byte red = 1;
+                byte green = 2;
+                byte blue = 3;
+                byte alpha = 4;
+
+                using (PixelRow<TColor, TPacked> row = new PixelRow<TColor, TPacked>(1, ComponentOrder.ZYXW))
+                {
+                    row.Bytes[0] = blue;
+                    row.Bytes[1] = green;
+                    row.Bytes[2] = red;
+                    row.Bytes[3] = alpha;
+
+                    pixels.CopyFrom(row, 0);
+
+                    Color color = (Color) (object) pixels[0, 0];
+                    Assert.Equal(red, color.R);
+                    Assert.Equal(green, color.G);
+                    Assert.Equal(blue, color.B);
+                    Assert.Equal(alpha, color.A);
+                }
+            }
+        }
+
+        private static void CopyToZYX<TColor, TPacked>(Image<TColor, TPacked> image)
+          where TColor : struct, IPackedPixel<TPacked>
+            where TPacked : struct
+        {
+            using (PixelAccessor<TColor, TPacked> pixels = image.Lock())
+            {
+                byte red = 1;
+                byte green = 2;
+                byte blue = 3;
+
+                using (PixelRow<TColor, TPacked> row = new PixelRow<TColor, TPacked>(1, ComponentOrder.ZYX))
+                {
+                    pixels[0, 0] = (TColor) (object) new Color(red, green, blue);
+
+                    pixels.CopyTo(row, 0);
+
+                    Assert.Equal(blue, row.Bytes[0]);
+                    Assert.Equal(green, row.Bytes[1]);
+                    Assert.Equal(red, row.Bytes[2]);
+                }
+            }
+        }
+
+        private static void CopyToZYXW<TColor, TPacked>(Image<TColor, TPacked> image)
+          where TColor : struct, IPackedPixel<TPacked>
+            where TPacked : struct
+        {
+            using (PixelAccessor<TColor, TPacked> pixels = image.Lock())
+            {
+                byte red = 1;
+                byte green = 2;
+                byte blue = 3;
+                byte alpha = 4;
+
+                using (PixelRow<TColor, TPacked> row = new PixelRow<TColor, TPacked>(1, ComponentOrder.ZYXW))
+                {
+                    pixels[0, 0] = (TColor) (object) new Color(red, green, blue, alpha);
+
+                    pixels.CopyTo(row, 0);
+
+                    Assert.Equal(blue, row.Bytes[0]);
+                    Assert.Equal(green, row.Bytes[1]);
+                    Assert.Equal(red, row.Bytes[2]);
+                    Assert.Equal(alpha, row.Bytes[3]);
+                }
+            }
+        }
+    }
+}