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Add gravity timing change.

This commit is contained in:
smoogipooo 2017-06-02 15:30:59 +09:00
parent d75bbb2b88
commit 563f746acf
2 changed files with 51 additions and 16 deletions

View File

@ -8,11 +8,11 @@ namespace osu.Game.Rulesets.Mania.Timing.Drawables
{
public class DrawableGravityTimingChange : DrawableTimingChange
{
private const double acceleration = 9.8f;
private const double terminal_velocity = 50f;
private const double duration = 2000;
// Amount of time to travel this container such that
// at time = 0, gravityTime = timeSpan and
// at time = travel_time, gravityTime = 0
// Where gravityTime is used as the position of the content
private const double travel_time = 1000;
public DrawableGravityTimingChange(TimingChange timingChange)
: base(timingChange)
@ -23,17 +23,52 @@ namespace osu.Game.Rulesets.Mania.Timing.Drawables
{
base.Update();
var parent = (TimingChangeContainer)Parent;
// The gravity-adjusted start position
float startY = (float)computeGravityTime(TimingChange.Time);
// The gravity-adjusted end position
float endY = (float)computeGravityTime(TimingChange.Time + Content.RelativeCoordinateSpace.Y);
double elapsed = Math.Max(0, Time.Current - TimingChange.Time);
// @ Current == TimingChange.Time - duration -> Y = TimingChange.Time
// @ Current == TimingChange.Time -> Y = 0
// @ Current == TimingChange.Time + x -> Y = -f(x)
double acceleration = elapsed / 2 / 1000 / 1000;
Content.Y = (float)(TimingChange.Time - 1 / 2f * acceleration * elapsed * elapsed);
Content.Y = startY;
Content.Height = endY - startY;
}
/// <summary>
/// Applies gravity to a time value based on the current time.
/// </summary>
/// <param name="time">The time value gravity should be applied to.</param>
/// <returns>The time after gravity is applied to <paramref name="time"/>.</returns>
private double computeGravityTime(double time)
{
double relativeTime = relativeTimeAt(time);
// The sign of the relative time, this is used to apply backwards acceleration leading into startTime
double sign = relativeTime < 0 ? -1 : 1;
return timeSpan - acceleration / 2 * relativeTime * relativeTime * sign;
}
/// <summary>
/// The time spanned by this container.
/// </summary>
private double timeSpan => RelativeCoordinateSpace.Y;
/// <summary>
/// The acceleration due to "gravity" of the content of this container.
/// </summary>
private double acceleration => 2 * timeSpan / travel_time / travel_time;
/// <summary>
/// Computes the current time relative to <paramref name="time"/>, accounting for <see cref="travel_time"/>.
/// </summary>
/// <param name="time">The non-offset time.</param>
/// <returns>The current time relative to <paramref name="time"/> - <see cref="travel_time"/>. </returns>
private double relativeTimeAt(double time) => Time.Current - time + travel_time;
/// <summary>
/// The velocity of the content of this container at a time.
/// </summary>
/// <param name="time">The non-offset time.</param>
/// <returns>The velocity at <paramref name="time"/>.</returns>
private double velocityAt(double time) => acceleration * relativeTimeAt(time);
}
}

View File

@ -10,7 +10,7 @@ namespace osu.Game.Rulesets.Mania.Timing.Drawables
{
public abstract class DrawableTimingChange : Container<DrawableHitObject>
{
protected readonly TimingChange TimingChange;
public readonly TimingChange TimingChange;
protected override Container<DrawableHitObject> Content => content;
private readonly Container<DrawableHitObject> content;