Add HalfVector4

src/ImageSharp/Colors/PackedPixel/HalfVector4.cs

@@ -0,0 +1,182 @@
+// <copyright file="HalfVector4.cs" company="James Jackson-South">
+// Copyright (c) James Jackson-South and contributors.
+// Licensed under the Apache License, Version 2.0.
+// </copyright>
+
+namespace ImageSharp
+{
+    using System;
+    using System.Numerics;
+
+    /// <summary>
+    /// Packed pixel type containing four 16-bit floating-point values.
+    /// </summary>
+    public struct HalfVector4 : IPackedPixel<ulong>, IEquatable<HalfVector4>
+    {
+        /// <summary>
+        /// The maximum byte value.
+        /// </summary>
+        private static readonly Vector4 MaxBytes = new Vector4(255);
+
+        /// <summary>
+        /// The half vector value.
+        /// </summary>
+        private static readonly Vector4 Half = new Vector4(0.5F);
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="HalfVector4"/> struct.
+        /// </summary>
+        /// <param name="x">The x-component.</param>
+        /// <param name="y">The y-component.</param>
+        /// <param name="z">The z-component.</param>
+        /// <param name="w">The w-component.</param>
+        public HalfVector4(float x, float y, float z, float w)
+        {
+            var vector = new Vector4(x, y, z, w);
+            this.PackedValue = PackHelper(ref vector);
+        }
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="HalfVector4"/> struct.
+        /// </summary>
+        /// <param name="vector">A vector containing the initial values for the components</param>
+        public HalfVector4(Vector4 vector)
+        {
+            this.PackedValue = PackHelper(ref vector);
+        }
+
+        /// <inheritdoc />
+        public ulong PackedValue { get; set; }
+
+        /// <summary>
+        /// Compares two <see cref="HalfVector2"/> objects for equality.
+        /// </summary>
+        /// <param name="left">
+        /// The <see cref="HalfVector2"/> on the left side of the operand.
+        /// </param>
+        /// <param name="right">
+        /// The <see cref="HalfVector2"/> on the right side of the operand.
+        /// </param>
+        /// <returns>
+        /// True if the <paramref name="left"/> parameter is equal to the <paramref name="right"/> parameter; otherwise, false.
+        /// </returns>
+        public static bool operator ==(HalfVector4 left, HalfVector4 right)
+        {
+            return left.Equals(right);
+        }
+
+        /// <summary>
+        /// Compares two <see cref="HalfVector2"/> objects for equality.
+        /// </summary>
+        /// <param name="left">
+        /// The <see cref="HalfVector2"/> on the left side of the operand.
+        /// </param>
+        /// <param name="right">
+        /// The <see cref="HalfVector2"/> on the right side of the operand.
+        /// </param>
+        /// <returns>
+        /// True if the <paramref name="left"/> parameter is not equal to the <paramref name="right"/> parameter; otherwise, false.
+        /// </returns>
+        public static bool operator !=(HalfVector4 left, HalfVector4 right)
+        {
+            return !left.Equals(right);
+        }
+
+        /// <inheritdoc />
+        public void PackFromVector4(Vector4 vector)
+        {
+            this.PackedValue = PackHelper(ref vector);
+        }
+
+        /// <inheritdoc />
+        public Vector4 ToVector4()
+        {
+            return new Vector4(
+                HalfTypeHelper.Unpack((ushort)this.PackedValue),
+                HalfTypeHelper.Unpack((ushort)(this.PackedValue >> 0x10)),
+                HalfTypeHelper.Unpack((ushort)(this.PackedValue >> 0x20)),
+                HalfTypeHelper.Unpack((ushort)(this.PackedValue >> 0x30)));
+        }
+
+        /// <inheritdoc />
+        public void PackFromBytes(byte x, byte y, byte z, byte w)
+        {
+            this.PackFromVector4(new Vector4(x, y, z, w) / MaxBytes);
+        }
+
+        /// <inheritdoc />
+        public void ToBytes(byte[] bytes, int startIndex, ComponentOrder componentOrder)
+        {
+            Vector4 vector = this.ToVector4();
+            vector *= MaxBytes;
+            vector += Half;
+            vector = Vector4.Clamp(vector, Vector4.Zero, MaxBytes);
+
+            switch (componentOrder)
+            {
+                case ComponentOrder.ZYX:
+                    bytes[startIndex] = (byte)vector.Z;
+                    bytes[startIndex + 1] = (byte)vector.Y;
+                    bytes[startIndex + 2] = (byte)vector.X;
+                    break;
+                case ComponentOrder.ZYXW:
+                    bytes[startIndex] = (byte)vector.Z;
+                    bytes[startIndex + 1] = (byte)vector.Y;
+                    bytes[startIndex + 2] = (byte)vector.X;
+                    bytes[startIndex + 3] = (byte)vector.W;
+                    break;
+                case ComponentOrder.XYZ:
+                    bytes[startIndex] = (byte)vector.X;
+                    bytes[startIndex + 1] = (byte)vector.Y;
+                    bytes[startIndex + 2] = (byte)vector.Z;
+                    break;
+                case ComponentOrder.XYZW:
+                    bytes[startIndex] = (byte)vector.X;
+                    bytes[startIndex + 1] = (byte)vector.Y;
+                    bytes[startIndex + 2] = (byte)vector.Z;
+                    bytes[startIndex + 3] = (byte)vector.W;
+                    break;
+                default:
+                    throw new NotSupportedException();
+            }
+        }
+
+        /// <inheritdoc />
+        public override string ToString()
+        {
+            return this.ToVector4().ToString();
+        }
+
+        /// <inheritdoc />
+        public override int GetHashCode()
+        {
+            return this.PackedValue.GetHashCode();
+        }
+
+        /// <inheritdoc />
+        public override bool Equals(object obj)
+        {
+            return (obj is HalfVector4) && this.Equals((HalfVector4)obj);
+        }
+
+        /// <inheritdoc />
+        public bool Equals(HalfVector4 other)
+        {
+            return this.PackedValue.Equals(other.PackedValue);
+        }
+
+        /// <summary>
+        /// Packs a <see cref="Vector4"/> into a <see cref="ulong"/>.
+        /// </summary>
+        /// <param name="vector">The vector containing the values to pack.</param>
+        /// <returns>The <see cref="ulong"/> containing the packed values.</returns>
+        private static ulong PackHelper(ref Vector4 vector)
+        {
+            ulong num4 = HalfTypeHelper.Pack(vector.X);
+            ulong num3 = (ulong)HalfTypeHelper.Pack(vector.Y) << 0x10;
+            ulong num2 = (ulong)HalfTypeHelper.Pack(vector.Z) << 0x20;
+            ulong num1 = (ulong)HalfTypeHelper.Pack(vector.W) << 0x30;
+            return num4 | num3 | num2 | num1;
+        }
+    }
+}

tests/ImageSharp.Tests/Colors/PackedPixelTests.cs

@@ -322,6 +322,52 @@ namespace ImageSharp.Tests.Colors
             Assert.Equal(bgra, new byte[] { 0, 64, 128, 255 });
         }
 
+        [Fact]
+        public void HalfVector4()
+        {
+            // Test PackedValue
+            Assert.Equal(0uL, new HalfVector4(Vector4.Zero).PackedValue);
+            Assert.Equal(4323521613979991040uL, new HalfVector4(Vector4.One).PackedValue);
+            Assert.Equal(13547034390470638592uL, new HalfVector4(-Vector4.One).PackedValue);
+            Assert.Equal(15360uL, new HalfVector4(Vector4.UnitX).PackedValue);
+            Assert.Equal(1006632960uL, new HalfVector4(Vector4.UnitY).PackedValue);
+            Assert.Equal(65970697666560uL, new HalfVector4(Vector4.UnitZ).PackedValue);
+            Assert.Equal(4323455642275676160uL, new HalfVector4(Vector4.UnitW).PackedValue);
+            Assert.Equal(4035285078724390502uL, new HalfVector4(0.1f, 0.3f, 0.4f, 0.5f).PackedValue);
+
+            // Test ToVector4
+            Assert.True(Equal(Vector4.Zero, new HalfVector4(Vector4.Zero).ToVector4()));
+            Assert.True(Equal(Vector4.One, new HalfVector4(Vector4.One).ToVector4()));
+            Assert.True(Equal(-Vector4.One, new HalfVector4(-Vector4.One).ToVector4()));
+            Assert.True(Equal(Vector4.UnitX, new HalfVector4(Vector4.UnitX).ToVector4()));
+            Assert.True(Equal(Vector4.UnitY, new HalfVector4(Vector4.UnitY).ToVector4()));
+            Assert.True(Equal(Vector4.UnitZ, new HalfVector4(Vector4.UnitZ).ToVector4()));
+            Assert.True(Equal(Vector4.UnitW, new HalfVector4(Vector4.UnitW).ToVector4()));
+
+            // Test ordering
+            float x = .25F;
+            float y = .5F;
+            float z = .75F;
+            float w = 1F;
+
+            byte[] rgb = new byte[3];
+            byte[] rgba = new byte[4];
+            byte[] bgr = new byte[3];
+            byte[] bgra = new byte[4];
+
+            new HalfVector4(x, y, z, w).ToBytes(rgb, 0, ComponentOrder.XYZ);
+            Assert.Equal(rgb, new byte[] { 64, 128, 191 });
+
+            new HalfVector4(x, y, z, w).ToBytes(rgba, 0, ComponentOrder.XYZW);
+            Assert.Equal(rgba, new byte[] { 64, 128, 191, 255 });
+
+            new HalfVector4(x, y, z, w).ToBytes(bgr, 0, ComponentOrder.ZYX);
+            Assert.Equal(bgr, new byte[] { 191, 128, 64 });
+
+            new HalfVector4(x, y, z, w).ToBytes(bgra, 0, ComponentOrder.ZYXW);
+            Assert.Equal(bgra, new byte[] { 191, 128, 64, 255 });
+        }
+
         // Comparison helpers with small tolerance to allow for floating point rounding during computations.
         public static bool Equal(float a, float b)
         {

tests/ImageSharp.Tests/Formats/GeneralFormatTests.cs

@@ -57,6 +57,8 @@ namespace ImageSharp.Tests
                 // Image<Bgra5551, ushort> image = file.CreateImage().To<Bgra5551, ushort>();
                 // Image<Byte4, uint> image = file.CreateImage().To<Byte4, uint>();
                 // Image<HalfSingle, ushort> image = file.CreateImage().To<HalfSingle, ushort>();
+                // Image<HalfVector2, uint> image = file.CreateImage().To<HalfVector2, uint>();
+                // Image<HalfVector4, ulong> image = file.CreateImage().To<HalfVector4, ulong>();
 
                 using (FileStream output = File.OpenWrite($"{path}/{file.FileName}"))
                 {