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Commit Description:
Add timers for Simulation and various engines...
Commit Description:
Add timers for Simulation and various engines Starting to add additional timers for different stages of the process of updating in order to get more insight into what is slowing it down. The update takes 9ms, which is much longer than it used to. Engine-specific timers are coming later.
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FNA/src/MathHelper.cs
416 lines | 11.8 KiB | text/x-csharp | CSharpLexer
Early working version (including all dependencies, lol).
r0 #region License
/* FNA - XNA4 Reimplementation for Desktop Platforms
* Copyright 2009-2020 Ethan Lee and the MonoGame Team
*
* Released under the Microsoft Public License.
* See LICENSE for details.
*/
/* Derived from code by the Mono.Xna Team (Copyright 2006).
* Released under the MIT License. See monoxna.LICENSE for details.
*/
#endregion
#region Using Statements
using System;
#endregion
namespace Microsoft.Xna.Framework
{
/// <summary>
/// Contains commonly used precalculated values and mathematical operations.
/// </summary>
public static class MathHelper
{
#region Public Constants
/// <summary>
/// Represents the mathematical constant e(2.71828175).
/// </summary>
public const float E = (float) Math.E;
/// <summary>
/// Represents the log base ten of e(0.4342945).
/// </summary>
public const float Log10E = 0.4342945f;
/// <summary>
/// Represents the log base two of e(1.442695).
/// </summary>
public const float Log2E = 1.442695f;
/// <summary>
/// Represents the value of pi(3.14159274).
/// </summary>
public const float Pi = (float) Math.PI;
/// <summary>
/// Represents the value of pi divided by two(1.57079637).
/// </summary>
public const float PiOver2 = (float) (Math.PI / 2.0);
/// <summary>
/// Represents the value of pi divided by four(0.7853982).
/// </summary>
public const float PiOver4 = (float) (Math.PI / 4.0);
/// <summary>
/// Represents the value of pi times two(6.28318548).
/// </summary>
public const float TwoPi = (float) (Math.PI * 2.0);
#endregion
#region Internal Static Readonly Fields
internal static readonly float MachineEpsilonFloat = GetMachineEpsilonFloat();
#endregion
#region Public Static Methods
/// <summary>
/// Returns the Cartesian coordinate for one axis of a point that is defined by a
/// given triangle and two normalized barycentric (areal) coordinates.
/// </summary>
/// <param name="value1">
/// The coordinate on one axis of vertex 1 of the defining triangle.
/// </param>
/// <param name="value2">
/// The coordinate on the same axis of vertex 2 of the defining triangle.
/// </param>
/// <param name="value3">
/// The coordinate on the same axis of vertex 3 of the defining triangle.
/// </param>
/// <param name="amount1">
/// The normalized barycentric (areal) coordinate b2, equal to the weighting factor
/// for vertex 2, the coordinate of which is specified in value2.
/// </param>
/// <param name="amount2">
/// The normalized barycentric (areal) coordinate b3, equal to the weighting factor
/// for vertex 3, the coordinate of which is specified in value3.
/// </param>
/// <returns>
/// Cartesian coordinate of the specified point with respect to the axis being used.
/// </returns>
public static float Barycentric(
float value1,
float value2,
float value3,
float amount1,
float amount2
) {
return value1 + (value2 - value1) * amount1 + (value3 - value1) * amount2;
}
/// <summary>
/// Performs a Catmull-Rom interpolation using the specified positions.
/// </summary>
/// <param name="value1">The first position in the interpolation.</param>
/// <param name="value2">The second position in the interpolation.</param>
/// <param name="value3">The third position in the interpolation.</param>
/// <param name="value4">The fourth position in the interpolation.</param>
/// <param name="amount">Weighting factor.</param>
/// <returns>A position that is the result of the Catmull-Rom interpolation.</returns>
public static float CatmullRom(
float value1,
float value2,
float value3,
float value4,
float amount
) {
/* Using formula from http://www.mvps.org/directx/articles/catmull/
* Internally using doubles not to lose precision.
*/
double amountSquared = amount * amount;
double amountCubed = amountSquared * amount;
return (float) (
0.5 *
(
((2.0 * value2 + (value3 - value1) * amount) +
((2.0 * value1 - 5.0 * value2 + 4.0 * value3 - value4) * amountSquared) +
(3.0 * value2 - value1 - 3.0 * value3 + value4) * amountCubed)
)
);
}
/// <summary>
/// Restricts a value to be within a specified range.
/// </summary>
/// <param name="value">The value to clamp.</param>
/// <param name="min">
/// The minimum value. If <c>value</c> is less than <c>min</c>, <c>min</c>
/// will be returned.
/// </param>
/// <param name="max">
/// The maximum value. If <c>value</c> is greater than <c>max</c>, <c>max</c>
/// will be returned.
/// </param>
/// <returns>The clamped value.</returns>
public static float Clamp(float value, float min, float max)
{
// First we check to see if we're greater than the max.
value = (value > max) ? max : value;
// Then we check to see if we're less than the min.
value = (value < min) ? min : value;
// There's no check to see if min > max.
return value;
}
/// <summary>
/// Calculates the absolute value of the difference of two values.
/// </summary>
/// <param name="value1">Source value.</param>
/// <param name="value2">Source value.</param>
/// <returns>Distance between the two values.</returns>
public static float Distance(float value1, float value2)
{
return Math.Abs(value1 - value2);
}
/// <summary>
/// Performs a Hermite spline interpolation.
/// </summary>
/// <param name="value1">Source position.</param>
/// <param name="tangent1">Source tangent.</param>
/// <param name="value2">Source position.</param>
/// <param name="tangent2">Source tangent.</param>
/// <param name="amount">Weighting factor.</param>
/// <returns>The result of the Hermite spline interpolation.</returns>
public static float Hermite(
float value1,
float tangent1,
float value2,
float tangent2,
float amount
) {
/* All transformed to double not to lose precision
* Otherwise, for high numbers of param:amount the result is NaN instead
* of Infinity.
*/
double v1 = value1, v2 = value2, t1 = tangent1, t2 = tangent2, s = amount;
double result;
double sCubed = s * s * s;
double sSquared = s * s;
if (WithinEpsilon(amount, 0f))
{
result = value1;
}
else if (WithinEpsilon(amount, 1f))
{
result = value2;
}
else
{
result = (
((2 * v1 - 2 * v2 + t2 + t1) * sCubed) +
((3 * v2 - 3 * v1 - 2 * t1 - t2) * sSquared) +
(t1 * s) +
v1
);
}
return (float) result;
}
/// <summary>
/// Linearly interpolates between two values.
/// </summary>
/// <param name="value1">Source value.</param>
/// <param name="value2">Source value.</param>
/// <param name="amount">
/// Value between 0 and 1 indicating the weight of value2.
/// </param>
/// <returns>Interpolated value.</returns>
/// <remarks>
/// This method performs the linear interpolation based on the following formula.
/// <c>value1 + (value2 - value1) * amount</c>
/// Passing amount a value of 0 will cause value1 to be returned, a value of 1 will
/// cause value2 to be returned.
/// </remarks>
public static float Lerp(float value1, float value2, float amount)
{
return value1 + (value2 - value1) * amount;
}
/// <summary>
/// Returns the greater of two values.
/// </summary>
/// <param name="value1">Source value.</param>
/// <param name="value2">Source value.</param>
/// <returns>The greater value.</returns>
public static float Max(float value1, float value2)
{
return value1 > value2 ? value1 : value2;
}
/// <summary>
/// Returns the lesser of two values.
/// </summary>
/// <param name="value1">Source value.</param>
/// <param name="value2">Source value.</param>
/// <returns>The lesser value.</returns>
public static float Min(float value1, float value2)
{
return value1 < value2 ? value1 : value2;
}
/// <summary>
/// Interpolates between two values using a cubic equation.
/// </summary>
/// <param name="value1">Source value.</param>
/// <param name="value2">Source value.</param>
/// <param name="amount">Weighting value.</param>
/// <returns>Interpolated value.</returns>
public static float SmoothStep(float value1, float value2, float amount)
{
/* It is expected that 0 < amount < 1.
* If amount < 0, return value1.
* If amount > 1, return value2.
*/
float result = MathHelper.Clamp(amount, 0f, 1f);
result = MathHelper.Hermite(value1, 0f, value2, 0f, result);
return result;
}
/// <summary>
/// Converts radians to degrees.
/// </summary>
/// <param name="radians">The angle in radians.</param>
/// <returns>The angle in degrees.</returns>
/// <remarks>
/// This method uses double precision internally, though it returns single float.
/// Factor = 180 / pi
/// </remarks>
public static float ToDegrees(float radians)
{
return (float) (radians * 57.295779513082320876798154814105);
}
/// <summary>
/// Converts degrees to radians.
/// </summary>
/// <param name="degrees">The angle in degrees.</param>
/// <returns>The angle in radians.</returns>
/// <remarks>
/// This method uses double precision internally, though it returns single float.
/// Factor = pi / 180
/// </remarks>
public static float ToRadians(float degrees)
{
return (float) (degrees * 0.017453292519943295769236907684886);
}
/// <summary>
/// Reduces a given angle to a value between pi and -pi.
/// </summary>
/// <param name="angle">The angle to reduce, in radians.</param>
/// <returns>The new angle, in radians.</returns>
public static float WrapAngle(float angle)
{
if ((angle > -Pi) && (angle <= Pi))
{
return angle;
}
angle %= TwoPi;
if (angle <= -Pi)
{
return angle + TwoPi;
}
if (angle > Pi)
{
return angle - TwoPi;
}
return angle;
}
#endregion
#region Internal Static Methods
// FIXME: This could be an extension! ClampIntEXT? -flibit
/// <summary>
/// Restricts a value to be within a specified range.
/// </summary>
/// <param name="value">The value to clamp.</param>
/// <param name="min">
/// The minimum value. If <c>value</c> is less than <c>min</c>, <c>min</c>
/// will be returned.
/// </param>
/// <param name="max">
/// The maximum value. If <c>value</c> is greater than <c>max</c>, <c>max</c>
/// will be returned.
/// </param>
/// <returns>The clamped value.</returns>
internal static int Clamp(int value, int min, int max)
{
value = (value > max) ? max : value;
value = (value < min) ? min : value;
return value;
}
internal static bool WithinEpsilon(float floatA, float floatB)
{
return Math.Abs(floatA - floatB) < MachineEpsilonFloat;
}
internal static int ClosestMSAAPower(int value)
{
/* Checking for the highest power of two _after_ than the given int:
* http://graphics.stanford.edu/~seander/bithacks.html#RoundUpPowerOf2
* Take result, divide by 2, get the highest power of two _before_!
* -flibit
*/
if (value == 1)
{
// ... Except for 1, which is invalid for MSAA -flibit
return 0;
}
int result = value - 1;
result |= result >> 1;
result |= result >> 2;
result |= result >> 4;
result |= result >> 8;
result |= result >> 16;
result += 1;
if (result == value)
{
return result;
}
return result >> 1;
}
#endregion
#region Private Static Methods
/// <summary>
/// Find the current machine's Epsilon for the float data type.
/// (That is, the largest float, e, where e == 0.0f is true.)
/// </summary>
private static float GetMachineEpsilonFloat()
{
float machineEpsilon = 1.0f;
float comparison;
/* Keep halving the working value of machineEpsilon until we get a number that
* when added to 1.0f will still evaluate as equal to 1.0f.
*/
do
{
machineEpsilon *= 0.5f;
comparison = 1.0f + machineEpsilon;
}
while (comparison > 1.0f);
return machineEpsilon;
}
#endregion
}
}