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OsuDifficultyBeatmap enumeration logic made clearer, more documentation added.

This commit is contained in:
Péter Nemes 2017-06-06 15:39:37 +02:00
parent afb4443763
commit 01585027b1
7 changed files with 87 additions and 41 deletions

View File

@ -30,7 +30,7 @@ namespace osu.Game.Rulesets.Osu.OsuDifficulty
protected override double CalculateInternal(Dictionary<string, string> categoryDifficulty)
{
OsuDifficultyBeatmap beatmap = new OsuDifficultyBeatmap(Objects);
Skill[] skills = new Skill[]
Skill[] skills =
{
new Aim(),
new Speed()

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@ -12,6 +12,9 @@ namespace osu.Game.Rulesets.Osu.OsuDifficulty.Preprocessing
private readonly IEnumerator<OsuDifficultyHitObject> difficultyObjects;
private readonly Queue<OsuDifficultyHitObject> onScreen = new Queue<OsuDifficultyHitObject>();
/// <summary>
/// Creates an enumerable, which handles the preprocessing of HitObjects, getting them ready to be used in difficulty calculation.
/// </summary>
public OsuDifficultyBeatmap(List<OsuHitObject> objects)
{
// Sort HitObjects by StartTime - they are not correctly ordered in some cases.
@ -20,38 +23,40 @@ namespace osu.Game.Rulesets.Osu.OsuDifficulty.Preprocessing
difficultyObjects = createDifficultyObjectEnumerator(objects);
}
/// <summary>
/// Returns an enumerator that enumerates all difficulty objects in the beatmap.
/// The inner loop adds notes that appear on screen into a queue until we need to hit the next note,
/// the outer loop returns notes from this queue one at a time, only after they had to be hit, and should no longer be on screen.
/// This means that we can loop through every object that is on screen at the time when a new one appears,
/// allowing us to determine a reading strain for the note that just appeared.
/// </summary>
public IEnumerator<OsuDifficultyHitObject> GetEnumerator()
{
do
while (true)
{
// Add upcoming notes to the queue until we have at least one note that had been hit and can be dequeued.
// This means there is always at least one note in the queue unless we reached the end of the map.
bool hasNext;
do
{
hasNext = difficultyObjects.MoveNext();
if (onScreen.Count == 0 && !hasNext)
yield break; // Stop if we have an empty enumerator.
if (!difficultyObjects.MoveNext())
break; // New notes can't be added anymore, but we still need to dequeue and return the ones already on screen.
if (hasNext)
OsuDifficultyHitObject latest = difficultyObjects.Current;
// Calculate flow values here
foreach (OsuDifficultyHitObject h in onScreen)
{
OsuDifficultyHitObject latest = difficultyObjects.Current;
// Calculate flow values here
foreach (OsuDifficultyHitObject h in onScreen)
{
h.MsUntilHit -= latest.Ms;
// Calculate reading strain here
}
onScreen.Enqueue(latest);
h.TimeUntilHit -= latest.DeltaTime;
// Calculate reading strain here
}
}
while (onScreen.Peek().MsUntilHit > 0 && hasNext); // Keep adding new notes on screen while there is still time before we have to hit the next one.
onScreen.Enqueue(latest);
}
while (onScreen.Peek().TimeUntilHit > 0); // Keep adding new notes on screen while there is still time before we have to hit the next one.
if (onScreen.Count == 0) break; // We have reached the end of the map and enumerated all the notes.
yield return onScreen.Dequeue(); // Remove and return notes one by one that had to be hit before the latest note appeared.
}
while (onScreen.Count > 0);
}
IEnumerator IEnumerable.GetEnumerator() => GetEnumerator();

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@ -8,6 +8,9 @@ namespace osu.Game.Rulesets.Osu.OsuDifficulty.Preprocessing
{
public class OsuDifficultyHitObject
{
/// <summary>
/// The current note. Attributes are calculated relative to previous ones.
/// </summary>
public OsuHitObject BaseObject { get; }
/// <summary>
@ -18,14 +21,20 @@ namespace osu.Game.Rulesets.Osu.OsuDifficulty.Preprocessing
/// <summary>
/// Milliseconds elapsed since the StartTime of the previous note.
/// </summary>
public double Ms { get; private set; }
public double DeltaTime { get; private set; }
public double MsUntilHit { get; set; }
/// <summary>
/// Number of milliseconds until the note has to be hit.
/// </summary>
public double TimeUntilHit { get; set; }
private const int normalized_radius = 52;
private readonly OsuHitObject[] t;
/// <summary>
/// Constructs a wrapper around a HitObject calculating additional data required for difficulty calculation.
/// </summary>
public OsuDifficultyHitObject(OsuHitObject[] triangle)
{
t = triangle;
@ -51,8 +60,8 @@ namespace osu.Game.Rulesets.Osu.OsuDifficulty.Preprocessing
private void setTimingValues()
{
// Every timing inverval is hard capped at the equivalent of 375 BPM streaming speed as a safety measure.
Ms = Math.Max(40, t[0].StartTime - t[1].StartTime);
MsUntilHit = 450; // BaseObject.PreEmpt;
DeltaTime = Math.Max(40, t[0].StartTime - t[1].StartTime);
TimeUntilHit = 450; // BaseObject.PreEmpt;
}
}
}

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@ -10,6 +10,6 @@ namespace osu.Game.Rulesets.Osu.OsuDifficulty.Skills
protected override double SkillMultiplier => 26.25;
protected override double StrainDecayBase => 0.15;
protected override double StrainValue() => Math.Pow(Current.Distance, 0.99) / Current.Ms;
protected override double StrainValue() => Math.Pow(Current.Distance, 0.99) / Current.DeltaTime;
}
}

View File

@ -11,10 +11,25 @@ namespace osu.Game.Rulesets.Osu.OsuDifficulty.Skills
{
public abstract class Skill
{
/// <summary>
/// Strain values are multiplied by this number for the given skill. Used to balance the value of different skills between each other.
/// </summary>
protected abstract double SkillMultiplier { get; }
/// <summary>
/// Determines how quickly strain decays for the given skill.
/// For example a value of 0.15 indicates that strain decays to 15% of it's original value in one second.
/// </summary>
protected abstract double StrainDecayBase { get; }
/// <summary>
/// The note that will be processed.
/// </summary>
protected OsuDifficultyHitObject Current;
/// <summary>
/// Notes that were processed previously. They can affect the strain value of the current note.
/// </summary>
protected History<OsuDifficultyHitObject> Previous = new History<OsuDifficultyHitObject>(2); // Contained objects not used yet
private double currentStrain = 1; // We keep track of the strain level at all times throughout the beatmap.
@ -28,7 +43,7 @@ namespace osu.Game.Rulesets.Osu.OsuDifficulty.Skills
{
Current = h;
currentStrain *= strainDecay(Current.Ms);
currentStrain *= strainDecay(Current.DeltaTime);
if (!(Current.BaseObject is Spinner))
currentStrain += StrainValue() * SkillMultiplier;
@ -78,6 +93,9 @@ namespace osu.Game.Rulesets.Osu.OsuDifficulty.Skills
return difficulty;
}
/// <summary>
/// Calculates the strain value of the current note. This value is affected by previous notes.
/// </summary>
protected abstract double StrainValue();
private double strainDecay(double ms) => Math.Pow(StrainDecayBase, ms / 1000);

View File

@ -28,7 +28,7 @@ namespace osu.Game.Rulesets.Osu.OsuDifficulty.Skills
else
speedValue = 0.95;
return speedValue / Current.Ms;
return speedValue / Current.DeltaTime;
}
}
}
}

View File

@ -8,7 +8,7 @@ using System.Collections.Generic;
namespace osu.Game.Rulesets.Osu.OsuDifficulty.Utils
{
/// <summary>
/// An indexed stack with Push() only, which disposes items at the bottom once the size limit has been reached.
/// An indexed stack with Push() only, which disposes items at the bottom after the capacity is full.
/// Indexing starts at the top of the stack.
/// </summary>
public class History<T> : IEnumerable<T>
@ -16,17 +16,28 @@ namespace osu.Game.Rulesets.Osu.OsuDifficulty.Utils
public int Count { get; private set; }
private readonly T[] array;
private readonly int size;
private readonly int capacity;
private int marker; // Marks the position of the most recently added item.
public History(int size)
//
/// <summary>
/// Initializes a new instance of the History class that is empty and has the specified capacity.
/// </summary>
/// <param name="capacity">The number of items the History can hold.</param>
public History(int capacity)
{
this.size = size;
array = new T[size];
marker = size; // Set marker to the end of the array, outside of the indexed range by one.
if (capacity < 0)
throw new ArgumentOutOfRangeException();
this.capacity = capacity;
array = new T[capacity];
marker = capacity; // Set marker to the end of the array, outside of the indexed range by one.
}
public T this[int i] // Index 0 returns the most recently added item.
/// <summary>
/// The most recently added item is returned at index 0.
/// </summary>
public T this[int i]
{
get
{
@ -34,8 +45,8 @@ namespace osu.Game.Rulesets.Osu.OsuDifficulty.Utils
throw new IndexOutOfRangeException();
i += marker;
if (i > size - 1)
i -= size;
if (i > capacity - 1)
i -= capacity;
return array[i];
}
@ -48,22 +59,25 @@ namespace osu.Game.Rulesets.Osu.OsuDifficulty.Utils
public void Push(T item) // Overwrite the oldest item instead of shifting every item by one with every addition.
{
if (marker == 0)
marker = size - 1;
marker = capacity - 1;
else
--marker;
array[marker] = item;
if (Count < size)
if (Count < capacity)
++Count;
}
/// <summary>
/// Returns an enumerator which enumerates items in the history starting from the most recently added item.
/// </summary>
public IEnumerator<T> GetEnumerator()
{
for (int i = marker; i < size; ++i)
for (int i = marker; i < capacity; ++i)
yield return array[i];
if (Count == size)
if (Count == capacity)
for (int i = 0; i < marker; ++i)
yield return array[i];
}