diff --git a/src/ImageSharp/ColorProfiles/Hsl.cs b/src/ImageSharp/ColorProfiles/Hsl.cs new file mode 100644 index 000000000..dd8772d96 --- /dev/null +++ b/src/ImageSharp/ColorProfiles/Hsl.cs @@ -0,0 +1,243 @@ +// Copyright (c) Six Labors. +// Licensed under the Six Labors Split License. + +using System.Numerics; +using System.Runtime.CompilerServices; + +namespace SixLabors.ImageSharp.ColorProfiles; + +/// +/// Represents a Hsl (hue, saturation, lightness) color. +/// +public readonly struct Hsl : IColorProfile +{ + private static readonly Vector3 Min = Vector3.Zero; + private static readonly Vector3 Max = new(360, 1, 1); + + /// + /// Initializes a new instance of the struct. + /// + /// The h hue component. + /// The s saturation component. + /// The l value (lightness) component. + [MethodImpl(MethodImplOptions.AggressiveInlining)] + public Hsl(float h, float s, float l) + : this(new Vector3(h, s, l)) + { + } + + /// + /// Initializes a new instance of the struct. + /// + /// The vector representing the h, s, l components. + [MethodImpl(MethodImplOptions.AggressiveInlining)] + public Hsl(Vector3 vector) + { + vector = Vector3.Clamp(vector, Min, Max); + this.H = vector.X; + this.S = vector.Y; + this.L = vector.Z; + } + + /// + /// Gets the hue component. + /// A value ranging between 0 and 360. + /// + public readonly float H { get; } + + /// + /// Gets the saturation component. + /// A value ranging between 0 and 1. + /// + public readonly float S { get; } + + /// + /// Gets the lightness component. + /// A value ranging between 0 and 1. + /// + public readonly float L { get; } + + /// + /// Compares two objects for equality. + /// + /// + /// The on the left side of the operand. + /// + /// The on the right side of the operand. + /// + /// True if the current left is equal to the parameter; otherwise, false. + /// + [MethodImpl(MethodImplOptions.AggressiveInlining)] + public static bool operator ==(Hsl left, Hsl right) => left.Equals(right); + + /// + /// Compares two objects for inequality. + /// + /// The on the left side of the operand. + /// The on the right side of the operand. + /// + /// True if the current left is unequal to the parameter; otherwise, false. + /// + [MethodImpl(MethodImplOptions.AggressiveInlining)] + public static bool operator !=(Hsl left, Hsl right) => !left.Equals(right); + + /// + public static Hsl FromProfileConnectingSpace(ColorConversionOptions options, in Rgb source) + { + float r = source.R; + float g = source.G; + float b = source.B; + + float max = MathF.Max(r, MathF.Max(g, b)); + float min = MathF.Min(r, MathF.Min(g, b)); + float chroma = max - min; + float h = 0F; + float s = 0F; + float l = (max + min) / 2F; + + if (MathF.Abs(chroma) < Constants.Epsilon) + { + return new Hsl(0F, s, l); + } + + if (MathF.Abs(r - max) < Constants.Epsilon) + { + h = (g - b) / chroma; + } + else if (MathF.Abs(g - max) < Constants.Epsilon) + { + h = 2F + ((b - r) / chroma); + } + else if (MathF.Abs(b - max) < Constants.Epsilon) + { + h = 4F + ((r - g) / chroma); + } + + h *= 60F; + if (h < 0F) + { + h += 360F; + } + + if (l <= .5F) + { + s = chroma / (max + min); + } + else + { + s = chroma / (2F - max - min); + } + + return new Hsl(h, s, l); + } + + /// + public static void FromProfileConnectionSpace(ColorConversionOptions options, ReadOnlySpan source, Span destination) + { + Guard.DestinationShouldNotBeTooShort(source, destination, nameof(destination)); + for (int i = 0; i < source.Length; i++) + { + Rgb rgb = source[i]; + destination[i] = FromProfileConnectingSpace(options, in rgb); + } + } + + /// + public Rgb ToProfileConnectingSpace(ColorConversionOptions options) + { + float rangedH = this.H / 360F; + float r = 0; + float g = 0; + float b = 0; + float s = this.S; + float l = this.L; + + if (MathF.Abs(l) > Constants.Epsilon) + { + if (MathF.Abs(s) < Constants.Epsilon) + { + r = g = b = l; + } + else + { + float temp2 = (l < .5F) ? l * (1F + s) : l + s - (l * s); + float temp1 = (2F * l) - temp2; + + r = GetColorComponent(temp1, temp2, rangedH + 0.3333333F); + g = GetColorComponent(temp1, temp2, rangedH); + b = GetColorComponent(temp1, temp2, rangedH - 0.3333333F); + } + } + + return new Rgb(r, g, b); + } + + /// + public static void ToProfileConnectionSpace(ColorConversionOptions options, ReadOnlySpan source, Span destination) + { + Guard.DestinationShouldNotBeTooShort(source, destination, nameof(destination)); + for (int i = 0; i < source.Length; i++) + { + Hsl hsl = source[i]; + destination[i] = hsl.ToProfileConnectingSpace(options); + } + } + + /// + public static ChromaticAdaptionWhitePointSource GetChromaticAdaptionWhitePointSource() + => ChromaticAdaptionWhitePointSource.RgbWorkingSpace; + + /// + [MethodImpl(MethodImplOptions.AggressiveInlining)] + public override int GetHashCode() => HashCode.Combine(this.H, this.S, this.L); + + /// + public override string ToString() => FormattableString.Invariant($"Hsl({this.H:#0.##}, {this.S:#0.##}, {this.L:#0.##})"); + + /// + public override bool Equals(object? obj) => obj is Hsl other && this.Equals(other); + + /// + [MethodImpl(MethodImplOptions.AggressiveInlining)] + public bool Equals(Hsl other) + => this.H.Equals(other.H) + && this.S.Equals(other.S) + && this.L.Equals(other.L); + + [MethodImpl(MethodImplOptions.AggressiveInlining)] + private static float GetColorComponent(float first, float second, float third) + { + third = MoveIntoRange(third); + if (third < 0.1666667F) + { + return first + ((second - first) * 6F * third); + } + + if (third < .5F) + { + return second; + } + + if (third < 0.6666667F) + { + return first + ((second - first) * (0.6666667F - third) * 6F); + } + + return first; + } + + [MethodImpl(MethodImplOptions.AggressiveInlining)] + private static float MoveIntoRange(float value) + { + if (value < 0F) + { + value++; + } + else if (value > 1F) + { + value--; + } + + return value; + } +}