using System;
using System.Runtime.CompilerServices;
// This file contains extra members for the Mathf class that aren't part of Godot's Core API.
// Math API that is also part of Core should go into Mathf.cs.
namespace Godot
{
public static partial class Mathf
{
// Define constants with Decimal precision and cast down to double or float.
/// <summary>
/// The natural number <c>e</c>.
/// </summary>
public const real_t E = (real_t)2.7182818284590452353602874714M; // 2.7182817f and 2.718281828459045
/// <summary>
/// The square root of 2.
/// </summary>
public const real_t Sqrt2 = (real_t)1.4142135623730950488016887242M; // 1.4142136f and 1.414213562373095
// Epsilon size should depend on the precision used.
private const float EpsilonF = 1e-06f;
private const double EpsilonD = 1e-14;
/// <summary>
/// A very small number used for float comparison with error tolerance.
/// 1e-06 with single-precision floats, but 1e-14 if <c>REAL_T_IS_DOUBLE</c>.
/// </summary>
#if REAL_T_IS_DOUBLE
public const real_t Epsilon = EpsilonD;
#else
public const real_t Epsilon = EpsilonF;
#endif
/// <summary>
/// Returns the amount of digits after the decimal place.
/// </summary>
/// <param name="s">The input value.</param>
/// <returns>The amount of digits.</returns>
[MethodImpl(MethodImplOptions.AggressiveInlining)]
public static int DecimalCount(double s)
{
return DecimalCount((decimal)s);
}
/// <summary>
/// Returns the amount of digits after the decimal place.
/// </summary>
/// <param name="s">The input <see langword="decimal"/> value.</param>
/// <returns>The amount of digits.</returns>
[MethodImpl(MethodImplOptions.AggressiveInlining)]
public static int DecimalCount(decimal s)
{
return BitConverter.GetBytes(decimal.GetBits(s)[3])[2];
}
/// <summary>
/// Rounds <paramref name="s"/> upward (towards positive infinity).
///
/// This is the same as <see cref="Ceil(float)"/>, but returns an <see langword="int"/>.
/// </summary>
/// <param name="s">The number to ceil.</param>
/// <returns>The smallest whole number that is not less than <paramref name="s"/>.</returns>
[MethodImpl(MethodImplOptions.AggressiveInlining)]
public static int CeilToInt(float s)
{
return (int)MathF.Ceiling(s);
}
/// <summary>
/// Rounds <paramref name="s"/> upward (towards positive infinity).
///
/// This is the same as <see cref="Ceil(double)"/>, but returns an <see langword="int"/>.
/// </summary>
/// <param name="s">The number to ceil.</param>
/// <returns>The smallest whole number that is not less than <paramref name="s"/>.</returns>
[MethodImpl(MethodImplOptions.AggressiveInlining)]
public static int CeilToInt(double s)
{
return (int)Math.Ceiling(s);
}
/// <summary>
/// Rounds <paramref name="s"/> downward (towards negative infinity).
///
/// This is the same as <see cref="Floor(float)"/>, but returns an <see langword="int"/>.
/// </summary>
/// <param name="s">The number to floor.</param>
/// <returns>The largest whole number that is not more than <paramref name="s"/>.</returns>
[MethodImpl(MethodImplOptions.AggressiveInlining)]
public static int FloorToInt(float s)
{
return (int)MathF.Floor(s);
}
/// <summary>
/// Rounds <paramref name="s"/> downward (towards negative infinity).
///
/// This is the same as <see cref="Floor(double)"/>, but returns an <see langword="int"/>.
/// </summary>
/// <param name="s">The number to floor.</param>
/// <returns>The largest whole number that is not more than <paramref name="s"/>.</returns>
[MethodImpl(MethodImplOptions.AggressiveInlining)]
public static int FloorToInt(double s)
{
return (int)Math.Floor(s);
}
/// <summary>
/// Rounds <paramref name="s"/> to the nearest whole number.
///
/// This is the same as <see cref="Round(float)"/>, but returns an <see langword="int"/>.
/// </summary>
/// <param name="s">The number to round.</param>
/// <returns>The rounded number.</returns>
[MethodImpl(MethodImplOptions.AggressiveInlining)]
public static int RoundToInt(float s)
{
return (int)MathF.Round(s);
}
/// <summary>
/// Rounds <paramref name="s"/> to the nearest whole number.
///
/// This is the same as <see cref="Round(double)"/>, but returns an <see langword="int"/>.
/// </summary>
/// <param name="s">The number to round.</param>
/// <returns>The rounded number.</returns>
[MethodImpl(MethodImplOptions.AggressiveInlining)]
public static int RoundToInt(double s)
{
return (int)Math.Round(s);
}
/// <summary>
/// Returns the sine and cosine of angle <paramref name="s"/> in radians.
/// </summary>
/// <param name="s">The angle in radians.</param>
/// <returns>The sine and cosine of that angle.</returns>
public static (float Sin, float Cos) SinCos(float s)
{
return MathF.SinCos(s);
}
/// <summary>
/// Returns the sine and cosine of angle <paramref name="s"/> in radians.
/// </summary>
/// <param name="s">The angle in radians.</param>
/// <returns>The sine and cosine of that angle.</returns>
public static (double Sin, double Cos) SinCos(double s)
{
return Math.SinCos(s);
}
/// <summary>
/// Returns <see langword="true"/> if <paramref name="a"/> and <paramref name="b"/> are approximately
/// equal to each other.
/// The comparison is done using the provided tolerance value.
/// If you want the tolerance to be calculated for you, use <see cref="IsEqualApprox(float, float)"/>.
/// </summary>
/// <param name="a">One of the values.</param>
/// <param name="b">The other value.</param>
/// <param name="tolerance">The pre-calculated tolerance value.</param>
/// <returns>A <see langword="bool"/> for whether or not the two values are equal.</returns>
public static bool IsEqualApprox(float a, float b, float tolerance)
{
// Check for exact equality first, required to handle "infinity" values.
if (a == b)
{
return true;
}
// Then check for approximate equality.
return Math.Abs(a - b) < tolerance;
}
/// <summary>
/// Returns <see langword="true"/> if <paramref name="a"/> and <paramref name="b"/> are approximately
/// equal to each other.
/// The comparison is done using the provided tolerance value.
/// If you want the tolerance to be calculated for you, use <see cref="IsEqualApprox(double, double)"/>.
/// </summary>
/// <param name="a">One of the values.</param>
/// <param name="b">The other value.</param>
/// <param name="tolerance">The pre-calculated tolerance value.</param>
/// <returns>A <see langword="bool"/> for whether or not the two values are equal.</returns>
public static bool IsEqualApprox(double a, double b, double tolerance)
{
// Check for exact equality first, required to handle "infinity" values.
if (a == b)
{
return true;
}
// Then check for approximate equality.
return Math.Abs(a - b) < tolerance;
}
}
}