/// <summary>
/// Adds a <see cref="FollowPointConnection"/> to this <see cref="FollowPointRenderer"/>.
/// </summary>
/// <param name="connection">The <see cref="FollowPointConnection"/> to add.</param>
/// <returns>The index of <paramref name="connection"/> in <see cref="connections"/>.</returns>
private void addConnection(FollowPointConnection connection)
{
// Groups are sorted by their start time when added such that the index can be used to post-process other surrounding connections
int index = connections.AddInPlace(connection, Comparer <FollowPointConnection> .Create((g1, g2) => g1.StartTime.Value.CompareTo(g2.StartTime.Value)));
if (index < connections.Count - 1)
{
// Update the connection's end point to the next connection's start point
// h1 -> -> -> h2
// connection nextGroup
FollowPointConnection nextConnection = connections[index + 1];
connection.End = nextConnection.Start;
}
else
{
// The end point may be non-null during re-ordering
connection.End = null;
}
if (index > 0)
{
// Update the previous connection's end point to the current connection's start point
// h1 -> -> -> h2
// prevGroup connection
FollowPointConnection previousConnection = connections[index - 1];
previousConnection.End = connection.Start;
}
AddInternal(connection);
}
/// <summary>
/// Adds a <see cref="FollowPointConnection"/> to this <see cref="FollowPointRenderer"/>.
/// </summary>
/// <param name="connection">The <see cref="FollowPointConnection"/> to add.</param>
/// <returns>The index of <paramref name="connection"/> in <see cref="connections"/>.</returns>
private void addConnection(FollowPointConnection connection)
{
// Groups are sorted by their start time when added such that the index can be used to post-process other surrounding connections
int index = connections.AddInPlace(connection, Comparer <FollowPointConnection> .Create((g1, g2) =>
{
int comp = g1.StartTime.Value.CompareTo(g2.StartTime.Value);
if (comp != 0)
{
return(comp);
}
// we always want to insert the new item after equal ones.
// this is important for beatmaps with multiple hitobjects at the same point in time.
// if we use standard comparison insert order, there will be a churn of connections getting re-updated to
// the next object at the point-in-time, adding a construction/disposal overhead (see FollowPointConnection.End implementation's ClearInternal).
// this is easily visible on https://osu.ppy.sh/beatmapsets/150945#osu/372245
return(-1);
}));
if (index < connections.Count - 1)
{
// Update the connection's end point to the next connection's start point
// h1 -> -> -> h2
// connection nextGroup
FollowPointConnection nextConnection = connections[index + 1];
connection.End = nextConnection.Start;
}
else
{
// The end point may be non-null during re-ordering
connection.End = null;
}
if (index > 0)
{
// Update the previous connection's end point to the current connection's start point
// h1 -> -> -> h2
// prevGroup connection
FollowPointConnection previousConnection = connections[index - 1];
previousConnection.End = connection.Start;
}
AddInternal(connection);
}
/// <summary>
/// Removes a <see cref="FollowPointConnection"/> from this <see cref="FollowPointRenderer"/>.
/// </summary>
/// <param name="connection">The <see cref="FollowPointConnection"/> to remove.</param>
/// <returns>Whether <paramref name="connection"/> was removed.</returns>
private void removeGroup(FollowPointConnection connection)
{
RemoveInternal(connection);
int index = connections.IndexOf(connection);
if (index > 0)
{
// Update the previous connection's end point to the next connection's start point
// h1 -> -> -> h2 -> -> -> h3
// prevGroup connection nextGroup
// The current connection's end point is used since there may not be a next connection
FollowPointConnection previousConnection = connections[index - 1];
previousConnection.End = connection.End;
}
connections.Remove(connection);
}
private void onStartTimeChanged(FollowPointConnection connection)
{
// Naive but can be improved if performance becomes an issue
removeGroup(connection);
addConnection(connection);
}