aboutsummaryrefslogtreecommitdiffstats
path: root/songmanagement/src/base/UBeatTimer.pas
blob: bc03de76eb466243730d8a1aa0af065499e24cf5 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
{* UltraStar Deluxe - Karaoke Game
 *
 * UltraStar Deluxe is the legal property of its developers, whose names
 * are too numerous to list here. Please refer to the COPYRIGHT
 * file distributed with this source distribution.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; see the file COPYING. If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301, USA.
 *
 * $URL$
 * $Id$
 *}

unit UBeatTimer;

interface

{$IFDEF FPC}
  {$MODE Delphi}
{$ENDIF}

{$I switches.inc}

uses
  UTime;

type
  (**
   * TLyricsState contains all information concerning the
   * state of the lyrics, e.g. the current beat or duration of the lyrics.
   *)
  TLyricsState = class
    private
      fTimer:        TRelativeTimer; // keeps track of the current time
      fSyncSource:   TSyncSource;
      fAvgSyncDiff:  real;
      fLastClock:    real;       // last master clock value
      // Note: do not use Timer.GetState() to check if lyrics are paused as
      // Timer.Pause() is used for synching.
      fPaused:       boolean;

      function Synchronize(LyricTime: real): real;
    public
      OldBeat:      integer;    // previous discovered beat
      CurrentBeat:  integer;    // current beat (rounded)
      MidBeat:      real;       // current beat (float)

      // now we use this for super synchronization!
      // only used when analyzing voice
      // TODO: change ...D to ...Detect(ed)
      OldBeatD:     integer;    // previous discovered beat
      CurrentBeatD: integer;    // current discovered beat (rounded)
      MidBeatD:     real;       // current discovered beat (float)

      // we use this for audible clicks
      // TODO: Change ...C to ...Click
      OldBeatC:     integer;    // previous discovered beat
      CurrentBeatC: integer;
      MidBeatC:     real;       // like CurrentBeatC

      OldLine:      integer;    // previous displayed sentence

      StartTime:    real;       // time till start of lyrics (= Gap)
      TotalTime:    real;       // total song time

      constructor Create();

      {**
       * Resets the LyricsState state.
       *}
      procedure Reset();

      procedure UpdateBeats();

      {**
       * Sets a master clock for this LyricsState. If no sync-source is set
       * or SyncSource is nil the internal timer is used.
       *}
      procedure SetSyncSource(SyncSource: TSyncSource);

      {**
       * Starts the timer. This is either done
       * - immediately if WaitForTrigger is false or
       * - after the first call to GetCurrentTime()/SetCurrentTime() or Start(false)
       *}
      procedure Start(WaitForTrigger: boolean = false);

      {**
       * Pauses the timer.
       * The counter is preserved and can be resumed by a call to Start().
       *}
      procedure Pause();

      {**
       * Stops the timer.
       * The counter is reset to 0.
       *}
      procedure Stop();

      (**
       * Returns/Sets the current song time (in seconds) used as base-timer for lyrics etc.
       * If GetCurrentTime()/SetCurrentTime() if Start() was called
       *)
      function GetCurrentTime(): real;
      procedure SetCurrentTime(Time: real);
  end;

implementation

uses
  UNote,
  ULog,
  SysUtils,
  Math;


constructor TLyricsState.Create();
begin
  // create a triggered timer, so we can Pause() it, set the time
  // and Resume() it afterwards for better synching.
  fTimer := TRelativeTimer.Create();

  // reset state
  Reset();
end;

procedure TLyricsState.Pause();
begin
  fTimer.Pause();
  fPaused := true;
end;

procedure TLyricsState.Start(WaitForTrigger: boolean);
begin
  fTimer.Start(WaitForTrigger);
  fPaused := false;
  fLastClock := -1;
  fAvgSyncDiff := -1;
end;

procedure TLyricsState.Stop();
begin
  fTimer.Stop();
  fPaused := false;
end;

procedure TLyricsState.SetCurrentTime(Time: real);
begin
  fTimer.SetTime(Time);
  fLastClock := -1;
  fAvgSyncDiff := -1;
end;

{.$DEFINE LOG_SYNC}

function TLyricsState.Synchronize(LyricTime: real): real;
var
  MasterClock: real;
  TimeDiff: real;
const
  AVG_HISTORY_FACTOR = 0.7;
  PAUSE_THRESHOLD = 0.010; // 10ms
  FORWARD_THRESHOLD = 0.010; // 10ms
begin
  MasterClock := fSyncSource.GetClock();
  Result := LyricTime;

  // do not sync if lyrics are paused externally or if the timestamp is old
  if (fPaused or (MasterClock = fLastClock)) then
    Exit;

  // calculate average time difference (some sort of weighted mean).
  // The bigger AVG_HISTORY_FACTOR is, the smoother is the average diff.
  // This is done as some timestamps might be wrong or even lower
  // than their predecessor.
  TimeDiff := MasterClock - LyricTime;
  if (fAvgSyncDiff = -1) then
    fAvgSyncDiff := TimeDiff
  else
    fAvgSyncDiff := TimeDiff * (1-AVG_HISTORY_FACTOR) +
                    fAvgSyncDiff * AVG_HISTORY_FACTOR;

  {$IFDEF LOG_SYNC}
  //Log.LogError(Format('TimeDiff: %.3f', [TimeDiff]));
  {$ENDIF}

  // do not go backwards in time as this could mess up the score
  if (fAvgSyncDiff > FORWARD_THRESHOLD) then
  begin
    {$IFDEF LOG_SYNC}
    Log.LogError('Sync: ' + floatToStr(MasterClock) + ' > ' + floatToStr(LyricTime));
    {$ENDIF}

    Result := LyricTime + fAvgSyncDiff;
    fTimer.SetTime(Result);
    fTimer.Start();
    fAvgSyncDiff := -1;
  end
  else if (fAvgSyncDiff < -PAUSE_THRESHOLD) then
  begin
    // wait until timer and master clock are in sync (> 10ms)
    fTimer.Pause();

    {$IFDEF LOG_SYNC}
    Log.LogError('Pause: ' + floatToStr(MasterClock) + ' < ' + floatToStr(LyricTime));
    {$ENDIF}
  end
  else if (fTimer.GetState = rtsPaused) and (fAvgSyncDiff >= 0) then
  begin
    fTimer.Start();

    {$IFDEF LOG_SYNC}
    Log.LogError('Unpause: ' + floatToStr(LyricTime));
    {$ENDIF}
  end;
  fLastClock := MasterClock;
end;

function TLyricsState.GetCurrentTime(): real;
var
  LyricTime: real;
begin
  LyricTime := fTimer.GetTime();
  if Assigned(fSyncSource) then
    Result := Synchronize(LyricTime)
  else
    Result := LyricTime;
end;

procedure TLyricsState.SetSyncSource(SyncSource: TSyncSource);
begin
  fSyncSource := SyncSource;
end;

(**
 * Resets the timer and state of the lyrics.
 * The timer will be stopped afterwards so you have to call Resume()
 * to start the lyrics timer. 
 *)
procedure TLyricsState.Reset();
begin
  Stop();
  fPaused := false;

  fSyncSource := nil;

  StartTime := 0;
  TotalTime := 0;

  OldBeat      := -1;
  MidBeat      := -1;
  CurrentBeat  := -1;

  OldBeatC     := -1;
  MidBeatC     := -1;
  CurrentBeatC := -1;

  OldBeatD     := -1;
  MidBeatD     := -1;
  CurrentBeatD := -1;
end;

(**
 * Updates the beat information (CurrentBeat/MidBeat/...) according to the
 * current lyric time.
 *)
procedure TLyricsState.UpdateBeats();
var
  CurLyricsTime: real;
begin
  CurLyricsTime := GetCurrentTime();

  OldBeat := CurrentBeat;
  MidBeat := GetMidBeat(CurLyricsTime - StartTime / 1000);
  CurrentBeat := Floor(MidBeat);

  OldBeatC := CurrentBeatC;
  MidBeatC := GetMidBeat(CurLyricsTime - StartTime / 1000);
  CurrentBeatC := Floor(MidBeatC);

  OldBeatD := CurrentBeatD;
  // MidBeatD = MidBeat with additional GAP
  MidBeatD := -0.5 + GetMidBeat(CurLyricsTime - (StartTime + 120 + 20) / 1000);
  CurrentBeatD := Floor(MidBeatD);
end;

end.