Net.Like.Xue.Tokyo/Assets/Plugins/Animancer/Internal/Mixer States/DirectionalMixerState.cs

313 lines
12 KiB
C#

// Animancer // https://kybernetik.com.au/animancer // Copyright 2018-2023 Kybernetik //
using System;
using System.Text;
using UnityEngine;
namespace Animancer
{
/// <summary>[Pro-Only]
/// An <see cref="AnimancerState"/> which blends an array of other states together based on a two dimensional
/// parameter and thresholds using Polar Gradient Band Interpolation.
/// </summary>
/// <remarks>
/// This mixer type is similar to the 2D Freeform Directional Blend Type in Mecanim Blend Trees.
/// <para></para>
/// Documentation: <see href="https://kybernetik.com.au/animancer/docs/manual/blending/mixers">Mixers</see>
/// </remarks>
/// https://kybernetik.com.au/animancer/api/Animancer/DirectionalMixerState
///
public class DirectionalMixerState : MixerState<Vector2>, ICopyable<DirectionalMixerState>
{
/************************************************************************************************************************/
/// <summary><see cref="MixerState{TParameter}.Parameter"/>.x.</summary>
public float ParameterX
{
get => Parameter.x;
set => Parameter = new Vector2(value, Parameter.y);
}
/// <summary><see cref="MixerState{TParameter}.Parameter"/>.y.</summary>
public float ParameterY
{
get => Parameter.y;
set => Parameter = new Vector2(Parameter.x, value);
}
/************************************************************************************************************************/
/// <inheritdoc/>
public override string GetParameterError(Vector2 value)
=> value.IsFinite() ? null : $"value.x and value.y {Strings.MustBeFinite}";
/************************************************************************************************************************/
/// <summary>Precalculated magnitudes of all thresholds to speed up the recalculation of weights.</summary>
private float[] _ThresholdMagnitudes;
/// <summary>Precalculated values to speed up the recalculation of weights.</summary>
private Vector2[][] _BlendFactors;
/// <summary>Indicates whether the <see cref="_BlendFactors"/> need to be recalculated.</summary>
private bool _BlendFactorsDirty = true;
/// <summary>The multiplier that controls how much an angle (in radians) is worth compared to normalized distance.</summary>
private const float AngleFactor = 2;
/************************************************************************************************************************/
/// <summary>
/// Called whenever the thresholds are changed. Indicates that the internal blend factors need to be
/// recalculated and calls <see cref="ForceRecalculateWeights"/>.
/// </summary>
public override void OnThresholdsChanged()
{
_BlendFactorsDirty = true;
base.OnThresholdsChanged();
}
/************************************************************************************************************************/
/// <summary>
/// Recalculates the weights of all <see cref="ManualMixerState.ChildStates"/> based on the current value of the
/// <see cref="MixerState{TParameter}.Parameter"/> and the thresholds.
/// </summary>
protected override void ForceRecalculateWeights()
{
WeightsAreDirty = false;
var childCount = ChildCount;
if (childCount == 0)
{
return;
}
else if (childCount == 1)
{
var state = GetChild(0);
state.Weight = 1;
return;
}
CalculateBlendFactors(childCount);
var parameterMagnitude = Parameter.magnitude;
float totalWeight = 0;
for (int i = 0; i < childCount; i++)
{
var state = GetChild(i);
if (state == null)
continue;
var blendFactors = _BlendFactors[i];
var thresholdI = GetThreshold(i);
var magnitudeI = _ThresholdMagnitudes[i];
// Convert the threshold to polar coordinates (distance, angle) and interpolate the weight based on those.
var differenceIToParameter = parameterMagnitude - magnitudeI;
var angleIToParameter = SignedAngle(thresholdI, Parameter) * AngleFactor;
float weight = 1;
for (int j = 0; j < childCount; j++)
{
if (j == i || GetChild(j) == null)
continue;
var magnitudeJ = _ThresholdMagnitudes[j];
var averageMagnitude = (magnitudeJ + magnitudeI) * 0.5f;
var polarIToParameter = new Vector2(
differenceIToParameter / averageMagnitude,
angleIToParameter);
var newWeight = 1 - Vector2.Dot(polarIToParameter, blendFactors[j]);
if (weight > newWeight)
weight = newWeight;
}
if (weight < 0.01f)
weight = 0;
state.Weight = weight;
totalWeight += weight;
}
NormalizeWeights(totalWeight);
}
/************************************************************************************************************************/
private void CalculateBlendFactors(int childCount)
{
if (!_BlendFactorsDirty)
return;
_BlendFactorsDirty = false;
// Resize the precalculated values.
if (_BlendFactors == null || _BlendFactors.Length != childCount)
{
_ThresholdMagnitudes = new float[childCount];
_BlendFactors = new Vector2[childCount][];
for (int i = 0; i < childCount; i++)
_BlendFactors[i] = new Vector2[childCount];
}
// Calculate the magnitude of each threshold.
for (int i = 0; i < childCount; i++)
{
_ThresholdMagnitudes[i] = GetThreshold(i).magnitude;
}
// Calculate the blend factors between each combination of thresholds.
for (int i = 0; i < childCount; i++)
{
var blendFactors = _BlendFactors[i];
var thresholdI = GetThreshold(i);
var magnitudeI = _ThresholdMagnitudes[i];
var j = 0;// i + 1;
for (; j < childCount; j++)
{
if (i == j)
continue;
var thresholdJ = GetThreshold(j);
var magnitudeJ = _ThresholdMagnitudes[j];
#if UNITY_ASSERTIONS
if (thresholdI == thresholdJ)
throw new ArgumentException(
$"Mixer has multiple identical thresholds.\n{GetDescription()}");
#endif
var averageMagnitude = (magnitudeI + magnitudeJ) * 0.5f;
// Convert the thresholds to polar coordinates (distance, angle) and interpolate the weight based on those.
var differenceIToJ = magnitudeJ - magnitudeI;
var angleIToJ = SignedAngle(thresholdI, thresholdJ);
var polarIToJ = new Vector2(
differenceIToJ / averageMagnitude,
angleIToJ * AngleFactor);
polarIToJ *= 1f / polarIToJ.sqrMagnitude;
// Each factor is used in [i][j] with it's opposite in [j][i].
blendFactors[j] = polarIToJ;
_BlendFactors[j][i] = -polarIToJ;
}
}
}
/************************************************************************************************************************/
private static float SignedAngle(Vector2 a, Vector2 b)
{
// If either vector is exactly at the origin, the angle is 0.
if ((a.x == 0 && a.y == 0) || (b.x == 0 && b.y == 0))
{
// Due to floating point error the formula below usually gives 0 but sometimes Pi,
// which screws up our other calculations so we need it to always be 0 properly.
return 0;
}
return Mathf.Atan2(
a.x * b.y - a.y * b.x,
a.x * b.x + a.y * b.y);
}
/************************************************************************************************************************/
/// <inheritdoc/>
public override AnimancerState Clone(AnimancerPlayable root)
{
var clone = new DirectionalMixerState();
clone.SetNewCloneRoot(root);
((ICopyable<DirectionalMixerState>)clone).CopyFrom(this);
return clone;
}
/************************************************************************************************************************/
/// <inheritdoc/>
void ICopyable<DirectionalMixerState>.CopyFrom(DirectionalMixerState copyFrom)
{
_ThresholdMagnitudes = copyFrom._ThresholdMagnitudes;
_BlendFactorsDirty = copyFrom._BlendFactorsDirty;
if (!_BlendFactorsDirty)
_BlendFactors = copyFrom._BlendFactors;
((ICopyable<MixerState<Vector2>>)this).CopyFrom(copyFrom);
}
/************************************************************************************************************************/
/// <inheritdoc/>
public override void AppendParameter(StringBuilder text, Vector2 parameter)
{
text.Append('(')
.Append(parameter.x)
.Append(", ")
.Append(parameter.y)
.Append(')');
}
/************************************************************************************************************************/
#region Inspector
/************************************************************************************************************************/
/// <inheritdoc/>
protected override int ParameterCount => 2;
/// <inheritdoc/>
protected override string GetParameterName(int index)
{
switch (index)
{
case 0: return "Parameter X";
case 1: return "Parameter Y";
default: throw new ArgumentOutOfRangeException(nameof(index));
}
}
/// <inheritdoc/>
protected override AnimatorControllerParameterType GetParameterType(int index) => AnimatorControllerParameterType.Float;
/// <inheritdoc/>
protected override object GetParameterValue(int index)
{
switch (index)
{
case 0: return ParameterX;
case 1: return ParameterY;
default: throw new ArgumentOutOfRangeException(nameof(index));
}
}
/// <inheritdoc/>
protected override void SetParameterValue(int index, object value)
{
switch (index)
{
case 0: ParameterX = (float)value; break;
case 1: ParameterY = (float)value; break;
default: throw new ArgumentOutOfRangeException(nameof(index));
}
}
/************************************************************************************************************************/
#endregion
/************************************************************************************************************************/
}
}