76 lines
3.9 KiB
C#

namespace Syntriax.Engine.Core;
/// <summary>
/// Represents a <see cref="Line2DEquation"/> in the form y = mx + b.
/// </summary>
/// <param name="slope">The slope of the line.</param>
/// <param name="offsetY">The Y intercept of the line.</param>
/// <remarks>
/// Initializes a new instance of the <see cref="Line2DEquation"/> struct with the specified slope and Y intercept.
/// </remarks>
[System.Diagnostics.DebuggerDisplay("y = {Slope}x + {OffsetY}")]
public readonly struct Line2DEquation(float slope, float offsetY)
{
/// <summary>
/// The slope of the <see cref="Line2DEquation"/>.
/// </summary>
public readonly float Slope = slope;
/// <summary>
/// The Y intercept of the <see cref="Line2DEquation"/>.
/// </summary>
public readonly float OffsetY = offsetY;
public static bool operator ==(Line2DEquation left, Line2DEquation right) => left.Slope == right.Slope && left.OffsetY == right.OffsetY;
public static bool operator !=(Line2DEquation left, Line2DEquation right) => left.Slope != right.Slope || left.OffsetY != right.OffsetY;
/// <summary>
/// Resolves the Y coordinate for a given X coordinate using the <see cref="Line2DEquation"/>.
/// </summary>
/// <param name="lineEquation">The <see cref="Line2DEquation"/> to resolve.</param>
/// <param name="x">The X coordinate for which to resolve the Y coordinate.</param>
/// <returns>The Y coordinate resolved using the <see cref="Line2DEquation"/>.</returns>
public static float Resolve(Line2DEquation lineEquation, float x) => lineEquation.Slope * x + lineEquation.OffsetY; // y = mx + b
/// <summary>
/// Checks if two <see cref="Line2DEquation"/> are approximately equal.
/// </summary>
/// <param name="left">The first <see cref="Line2DEquation"/> to compare.</param>
/// <param name="right">The second <see cref="Line2DEquation"/> to compare.</param>
/// <param name="epsilon">The epsilon range.</param>
/// <returns>True if the <see cref="Line2DEquation"/> are approximately equal; otherwise, false.</returns>
public static bool ApproximatelyEquals(Line2DEquation left, Line2DEquation right, float epsilon = float.Epsilon)
=> left.Slope.ApproximatelyEquals(right.Slope, epsilon) && left.OffsetY.ApproximatelyEquals(right.OffsetY, epsilon);
/// <summary>
/// Determines whether the specified object is equal to the current <see cref="Line2DEquation"/>.
/// </summary>
/// <param name="obj">The object to compare with the current <see cref="Line2DEquation"/>.</param>
/// <returns><see cref="true"/> if the specified object is equal to the current <see cref="Line2DEquation"/>; otherwise, <see cref="false"/>.</returns>
public override bool Equals(object? obj) => obj is Line2DEquation lineEquation && this == lineEquation;
/// <summary>
/// Generates a hash code for the <see cref="Line2DEquation"/>.
/// </summary>
/// <returns>A hash code for the <see cref="Line2DEquation"/>.</returns>
public override int GetHashCode() => System.HashCode.Combine(Slope, OffsetY);
/// <summary>
/// Converts the <see cref="Line2DEquation"/> to its string representation.
/// </summary>
/// <returns>A string representation of the <see cref="Line2DEquation"/>.</returns>
public override string ToString() => $"{nameof(Line2DEquation)}({Slope}, {OffsetY})";
}
/// <summary>
/// Provides extension methods for the <see cref="Line2DEquation"/> struct.
/// </summary>
public static class Line2DEquationExtensions
{
/// <inheritdoc cref="Line2DEquation.Resolve(Line2DEquation, float)" />
public static float Resolve(this Line2DEquation lineEquation, float x) => Line2DEquation.Resolve(lineEquation, x);
/// <inheritdoc cref="Line2DEquation.ApproximatelyEquals(Line2DEquation, Line2DEquation, float)" />
public static bool ApproximatelyEquals(this Line2DEquation left, Line2DEquation right, float epsilon = float.Epsilon) => Line2DEquation.ApproximatelyEquals(left, right, epsilon);
}