1 /***************************************************************************
2  *                                                                         *
3  *   LinuxSampler - modular, streaming capable sampler                     *
4  *                                                                         *
5  *   Copyright (C) 2003, 2004 by Benno Senoner and Christian Schoenebeck   *
6  *   Copyright (C) 2005 - 2021 Christian Schoenebeck                       *
7  *                                                                         *
8  *   This program is free software; you can redistribute it and/or modify  *
9  *   it under the terms of the GNU General Public License as published by  *
10  *   the Free Software Foundation; either version 2 of the License, or     *
11  *   (at your option) any later version.                                   *
12  *                                                                         *
13  *   This program is distributed in the hope that it will be useful,       *
14  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
15  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
16  *   GNU General Public License for more details.                          *
17  *                                                                         *
18  *   You should have received a copy of the GNU General Public License     *
19  *   along with this program; if not, write to the Free Software           *
20  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston,                 *
21  *   MA  02111-1307  USA                                                   *
22  ***************************************************************************/
23 
24 #ifndef __LS_EVENT_H__
25 #define __LS_EVENT_H__
26 
27 #include "../../common/global.h"
28 #include "../../common/RTMath.h"
29 #include "../../common/RTAVLTree.h"
30 #include "../../common/Pool.h"
31 #include "../EngineChannel.h"
32 #include "../../scriptvm/common.h"
33 
34 // On Windows RELATIVE might be defined as macro in wingdi.h, which would
35 // cause a compiler error of the same token used in this header file below.
36 // So we undefine that macro here for now (if present).
37 #ifdef RELATIVE
38 # warning Preprocessor conflict detected: Macro RELATIVE was declared by system headers; undefining it here.
39 # undef RELATIVE
40 #endif
41 
42 namespace LinuxSampler {
43 
44     // just symbol prototyping
45     class Event;
46     class SchedulerNode;
47     class ScriptEvent;
48     class ScheduledEvent;
49 
50     /**
51      * Data type used to schedule events sample point accurately both within, as
52      * well as beyond the scope of the current audio fragment cycle. The timing
53      * reflected by this data type is consecutively running for a very long
54      * time. Even with a sample rate of 96 kHz a scheduler time of this data
55      * type will not wrap before 6 million years. So in practice such time
56      * stamps are unique and will not repeat (unless the EventGenerator is
57      * reset).
58      */
59     typedef uint64_t sched_time_t;
60 
61     /**
62      * Generates Event objects and is responsible for resolving the position
63      * in the current audio fragment each Event actually belongs to.
64      */
65     class EventGenerator {
66         public:
67             EventGenerator(uint SampleRate);
68             void UpdateFragmentTime(uint SamplesToProcess);
69             void SetSampleRate(uint SampleRate);
70             Event CreateEvent();
71             Event CreateEvent(int32_t FragmentPos);
72 
73             template<typename T>
74             void scheduleAheadMicroSec(RTAVLTree<T>& queue, T& node, int32_t fragmentPosBase, uint64_t microseconds);
75 
76             RTList<ScheduledEvent>::Iterator popNextScheduledEvent(RTAVLTree<ScheduledEvent>& queue, Pool<ScheduledEvent>& pool, sched_time_t end);
77             RTList<ScriptEvent>::Iterator popNextScheduledScriptEvent(RTAVLTree<ScriptEvent>& queue, Pool<ScriptEvent>& pool, sched_time_t end);
78 
79             /**
80              * Returns the scheduler time for the first sample point of the
81              * current audio fragment cycle.
82              */
schedTimeAtCurrentFragmentStart()83             sched_time_t schedTimeAtCurrentFragmentStart() const {
84                 return uiTotalSamplesProcessed;
85             }
86 
87             /**
88              * Returns the scheduler time for the first sample point of the next
89              * audio fragment cycle.
90              */
schedTimeAtCurrentFragmentEnd()91             sched_time_t schedTimeAtCurrentFragmentEnd() const {
92                 return uiTotalSamplesProcessed + uiSamplesProcessed;
93             }
94 
95         protected:
96             typedef RTMath::time_stamp_t time_stamp_t;
ToFragmentPos(time_stamp_t TimeStamp)97             inline int32_t ToFragmentPos(time_stamp_t TimeStamp) {
98                 return int32_t (int32_t(TimeStamp - FragmentTime.begin) * FragmentTime.sample_ratio);
99             }
100             friend class Event;
101         private:
102             uint uiSampleRate;
103             uint uiSamplesProcessed;
104             struct __FragmentTime__ {
105                 time_stamp_t begin;        ///< Real time stamp of the beginning of this audio fragment cycle.
106                 time_stamp_t end;          ///< Real time stamp of the end of this audio fragment cycle.
107                 float        sample_ratio; ///< (Samples per cycle) / (Real time duration of cycle)
108             } FragmentTime;
109             sched_time_t uiTotalSamplesProcessed; ///< Total amount of sample points that have been processed since this EventGenerator object has been created. This is used to schedule instrument script events long time ahead in future (that is beyond the scope of the current audio fragment).
110     };
111 
112     /**
113      * Unique numeric ID of an event which can be used to retrieve access to
114      * the actual @c Event object. Once the event associated with a certain ID
115      * was released (back to its event pool), this numeric ID becomes invalid
116      * and Pool< Event >::fromID() will detect this circumstance and will
117      * return an invalid Iterator, and thus will prevent you from misusing an
118      * event which no longer "exists".
119      *
120      * Note that an @c Event object usually just "exists" for exactly one audio
121      * fragment cycle: that is it exists right from the beginning of the audio
122      * fragment cycle where it was caused (i.e. where its MIDI data was
123      * received by the respective engine channel) and will disappear
124      * automatically at the end of that audio fragment cycle.
125      */
126     typedef pool_element_id_t event_id_t;
127 
128     /**
129      * Unique numeric ID of a note which can be used to retrieve access to the
130      * actual @c Note object. Once the note associated with a certain ID was
131      * released (back to its note pool), this numeric ID becomes invalid and
132      * Pool< Note >::fromID() will detect this circumstance and will return
133      * an invalid Iterator, and thus will prevent you from misusing a note
134      * which no longer is "alive".
135      *
136      * A @c Note object exists right when the respective MIDI note-on event
137      * was received by the respective engine channel, and remains existent
138      * until the caused note and all its voices were finally freed (which might
139      * even be long time after the respective note-off event was received,
140      * depending on the duration of the voice's release stages etc.).
141      */
142     typedef pool_element_id_t note_id_t;
143 
144     /**
145      * Unique numeric ID of a script callback ID instance which can be used to
146      * retrieve access to the actual @c ScriptEvent object. Once the script
147      * callback instance associated with a certain ID stopped its execution
148      * (that is completely stopped, not just suspended) then this numeric ID
149      * becomes invalid and Pool< ScriptEvent >::fromID() will detect this
150      * circumstance and will return an invalid Iterator, and thus will prevent
151      * you from misusing a script callback instance which no longer "exists".
152      */
153     typedef pool_element_id_t script_callback_id_t;
154 
155     /**
156      * Events are usually caused by a MIDI source or an internal modulation
157      * controller like LFO or EG. An event should only be created by an
158      * EventGenerator!
159      *
160      * @see EventGenerator, ScriptEvent
161      */
162     class Event {
163         public:
Event()164             Event(){}
165             enum type_t {
166                 type_note_on, ///< (real) MIDI note-on event
167                 type_note_off, ///< (real) MIDI note-off event
168                 type_pitchbend, ///< MIDI pitch bend wheel change event
169                 type_control_change, ///< MIDI CC event
170                 type_rpn, ///< Transformed from a raw RPN CC MIDI event.
171                 type_nrpn, ///< Transformed from a raw NRPN CC MIDI event.
172                 type_sysex,           ///< MIDI system exclusive message
173                 type_cancel_release_key, ///< transformed either from a (real) MIDI note-on or sustain-pedal-down event
174                 type_release_key,     ///< transformed either from a (real) MIDI note-off or sustain-pedal-up event
175                 type_release_note,    ///< transformed from a type_stop_note event
176                 type_channel_pressure, ///< a.k.a. aftertouch
177                 type_note_pressure, ///< polyphonic key pressure (aftertouch)
178                 type_play_note, ///< caused by a call to built-in instrument script function play_note()
179                 type_stop_note, ///< caused by a call to built-in instrument script function note_off()
180                 type_kill_note, ///< caused by a call to built-in instrument script function fade_out()
181                 type_note_synth_param, ///< change a note's synthesis parameters (upon real-time instrument script function calls, i.e. change_vol(), change_tune(), change_pan(), etc.)
182             } Type;
183             enum synth_param_t {
184                 synth_param_volume,
185                 synth_param_volume_time,
186                 synth_param_volume_curve,
187                 synth_param_pitch,
188                 synth_param_pitch_time,
189                 synth_param_pitch_curve,
190                 synth_param_pan,
191                 synth_param_pan_time,
192                 synth_param_pan_curve,
193                 synth_param_cutoff,
194                 synth_param_resonance,
195                 synth_param_attack,
196                 synth_param_decay,
197                 synth_param_sustain,
198                 synth_param_release,
199                 synth_param_cutoff_attack,
200                 synth_param_cutoff_decay,
201                 synth_param_cutoff_sustain,
202                 synth_param_cutoff_release,
203                 synth_param_amp_lfo_depth,
204                 synth_param_amp_lfo_freq,
205                 synth_param_cutoff_lfo_depth,
206                 synth_param_cutoff_lfo_freq,
207                 synth_param_pitch_lfo_depth,
208                 synth_param_pitch_lfo_freq,
209             };
210             enum class ValueScope : unsigned char {
211                 /**
212                  * The new synthesis parameter value should be applied
213                  * relatively to itself (as normalized value range), and then
214                  * applied relatively against other sources (i.e. LFOs, EGs)
215                  * for the same synthesis parameter.
216                  */
217                 SELF_RELATIVE = 1,
218                 /**
219                  * The new synthesis paramater value of itself should be
220                  * replaced, and then applied relatively to other sources
221                  * (i.e. LFOs, EGs) for the same synthesis parameter.
222                  */
223                 RELATIVE = 0, //IMPORANT: must remain 0 because of the union structure below which would otherwise i.e. assign invalid pointers/IDs to Param.Note structure in Init()
224                 /**
225                  * The new synthesis parameter value should be applied
226                  * relatively to itself (as normalized value range), and then
227                  * applied directly (as normalized value range) as final value
228                  * of this synthesis chain, thus all other sources (i.e. LFOs,
229                  * EGs) should entirely be ignored.
230                  */
231                 FINAL_SELF_RELATIVE = 2,
232                 /**
233                  * The new synthesis parameter value of itself should be
234                  * replaced, and then applied directly (as normalized value
235                  * range) as final value of this synthesis chain, thus all other
236                  * sources (i.e. LFOs, EGs) should entirely be ignored.
237                  */
238                 FINAL_NORM = 3,
239                 /**
240                  * Same as @c FINAL_NORM, but this one is already in the native
241                  * unit (i.e. seconds, Hz) of this synthesis parameter.
242                  */
243                 FINAL_NATIVE = 4,
244             };
245             union {
246                 /// Note-on and note-off event specifics
247                 struct _Note {
248                     uint8_t Channel;     ///< MIDI channel (0..15)
249                     uint8_t Key;         ///< MIDI key number of note-on / note-off event.
250                     uint8_t Velocity;    ///< Trigger or release velocity of note-on / note-off event.
251                     int8_t  Layer;       ///< Layer index (usually only used if a note-on event has to be postponed, e.g. due to shortage of free voices).
252                     int8_t  ReleaseTrigger; ///< If new voice should be a release triggered voice (actually boolean field and usually only used if a note-on event has to be postponed, e.g. due to shortage of free voices).
253                     note_id_t ID;        ///< Unique numeric ID of the @c Note object associated with this note event.
254                     note_id_t ParentNoteID; ///< If not zero: Unique numeric ID of the parent @c Note object that shall become parent of resulting new Note object of this Event. So this is used to associate a new note with a previous note, i.e. to release the new note once the parent note was released.
255                     void*   pRegion;     ///< Engine specific pointer to instrument region
256                 } Note;
257                 /// Control change event specifics
258                 struct _CC {
259                     uint8_t Channel;     ///< MIDI channel (0..15)
260                     uint8_t Controller;  ///< MIDI controller number of control change event.
261                     uint8_t Value;       ///< Controller Value of control change event.
262                 } CC;
263                 /// Used for both RPN & NRPN events
264                 struct _RPN {
265                     uint8_t Channel;     ///< MIDI channel (0..15)
266                     uint16_t Parameter;  ///< Merged 14 bit representation of parameter number (that is MSB and LSB combined).
267                     uint16_t Value;      ///< Merged 14 bit representation of new (N)RPN value (that is MSB and LSB combined).
ParameterMSB__anon8b9b8e2d010a::_RPN268                     uint8_t ParameterMSB() const { return Parameter >> 7; }
ParameterLSB__anon8b9b8e2d010a::_RPN269                     uint8_t ParameterLSB() const { return Parameter & 127; }
ValueMSB__anon8b9b8e2d010a::_RPN270                     uint8_t ValueMSB() const { return Value >> 7; }
ValueLSB__anon8b9b8e2d010a::_RPN271                     uint8_t ValueLSB() const { return Value & 127; }
272                 } RPN, NRPN;
273                 /// Pitchbend event specifics
274                 struct _Pitch {
275                     uint8_t Channel;     ///< MIDI channel (0..15)
276                     int16_t Pitch;       ///< Pitch value of pitchbend event.
277                 } Pitch;
278                 /// MIDI system exclusive event specifics
279                 struct _Sysex {
280                     uint Size;           ///< Data length (in bytes) of MIDI system exclusive message.
281                 } Sysex;
282                 /// Channel Pressure (aftertouch) event specifics
283                 struct _ChannelPressure {
284                     uint8_t Channel; ///< MIDI channel (0..15)
285                     uint8_t Controller; ///< Should always be assigned to CTRL_TABLE_IDX_AFTERTOUCH.
286                     uint8_t Value;   ///< New aftertouch / pressure value for keys on that channel.
287                 } ChannelPressure;
288                 /// Polyphonic Note Pressure (aftertouch) event specifics
289                 struct _NotePressure {
290                     uint8_t Channel; ///< MIDI channel (0..15)
291                     uint8_t Key;     ///< MIDI note number where key pressure (polyphonic aftertouch) changed.
292                     uint8_t Value;   ///< New pressure value for note.
293                 } NotePressure;
294                 ///< Note synthesis parameter change event's specifics (used for real-time instrument script built-in functions which may alter synthesis parameters on note level).
295                 struct _NoteSynthParam {
296                     note_id_t     NoteID;   ///< ID of Note whose voices shall be modified.
297                     synth_param_t Type;     ///< Synthesis parameter which is to be changed.
298                     float         Delta;    ///< The value change that should be applied against the note's current synthesis parameter value.
299                     float         AbsValue; ///< New current absolute value of synthesis parameter (that is after @c Delta being applied).
300                     ValueScope    Scope;    ///< How @c Delta should be applied against @c AbsValue, and how @c AbsValue should then actually be applied to the synthesis chain.
301 
isFinal__anon8b9b8e2d010a::_NoteSynthParam302                     inline bool isFinal() const { return Scope >= ValueScope::FINAL_SELF_RELATIVE; }
303                 } NoteSynthParam;
304             } Param;
305             EngineChannel* pEngineChannel; ///< Pointer to the EngineChannel where this event occured on, NULL means Engine global event (e.g. SysEx message).
306             MidiInputPort* pMidiInputPort; ///< Pointer to the MIDI input port on which this event occured (NOTE: currently only for global events, that is SysEx messages)
307 
Init()308             inline void Init() {
309                 memset(&Param, 0, sizeof(Param));
310             }
FragmentPos()311             inline int32_t FragmentPos() {
312                 if (iFragmentPos >= 0) return iFragmentPos;
313                 iFragmentPos = pEventGenerator->ToFragmentPos(TimeStamp);
314                 if (iFragmentPos < 0) iFragmentPos = 0; // if event arrived shortly before the beginning of current fragment
315                 return iFragmentPos;
316             }
ResetFragmentPos()317             inline void ResetFragmentPos() {
318                 iFragmentPos = -1;
319             }
CopyTimeFrom(const Event & other)320             inline void CopyTimeFrom(const Event& other) {
321                 TimeStamp = other.TimeStamp;
322                 iFragmentPos = other.iFragmentPos;
323             }
SchedTime()324             inline sched_time_t SchedTime() {
325                 return pEventGenerator->schedTimeAtCurrentFragmentStart() + FragmentPos();
326             }
scopeBy_FinalRelativeUnit(bool bFinal,bool bRelative,bool bNativeUnit)327             inline static ValueScope scopeBy_FinalRelativeUnit(bool bFinal, bool bRelative, bool bNativeUnit) {
328                 if (!bFinal && bRelative)
329                     return ValueScope::SELF_RELATIVE;
330                 if (!bFinal)
331                     return ValueScope::RELATIVE;
332                 if (bRelative)
333                     return ValueScope::FINAL_SELF_RELATIVE;
334                 if (bNativeUnit)
335                     return ValueScope::FINAL_NATIVE;
336                 return ValueScope::FINAL_NORM;
337             }
338         protected:
339             typedef EventGenerator::time_stamp_t time_stamp_t;
340             Event(EventGenerator* pGenerator, EventGenerator::time_stamp_t Time);
341             Event(EventGenerator* pGenerator, int32_t FragmentPos);
342             friend class EventGenerator;
343         private:
344             EventGenerator* pEventGenerator; ///< Creator of the event.
345             time_stamp_t    TimeStamp;       ///< Time stamp of the event's occurence.
346             int32_t         iFragmentPos;    ///< Position in the current fragment this event refers to.
347     };
348 
prevEventOf(const Pool<Event>::Iterator & itEvent)349     inline Pool<Event>::Iterator prevEventOf(const Pool<Event>::Iterator& itEvent) {
350         if (!itEvent) return Pool<Event>::Iterator();
351         Pool<Event>::Iterator itPrev = itEvent;
352         return --itPrev;
353     }
354 
nextEventOf(const Pool<Event>::Iterator & itEvent)355     inline Pool<Event>::Iterator nextEventOf(const Pool<Event>::Iterator& itEvent) {
356         if (!itEvent) return Pool<Event>::Iterator();
357         Pool<Event>::Iterator itNext = itEvent;
358         return ++itNext;
359     }
360 
isPrevEventCCNr(const Pool<Event>::Iterator & itEvent,uint8_t CCNr)361     inline bool isPrevEventCCNr(const Pool<Event>::Iterator& itEvent, uint8_t CCNr) {
362         Pool<Event>::Iterator itPrev = prevEventOf(itEvent);
363         if (!itPrev) return false;
364         return itPrev->Type == Event::type_control_change &&
365                itPrev->Param.CC.Controller == CCNr;
366     }
367 
isNextEventCCNr(const Pool<Event>::Iterator & itEvent,uint8_t CCNr)368     inline bool isNextEventCCNr(const Pool<Event>::Iterator& itEvent, uint8_t CCNr) {
369         Pool<Event>::Iterator itNext = nextEventOf(itEvent);
370         if (!itNext) return false;
371         return itNext->Type == Event::type_control_change &&
372                itNext->Param.CC.Controller == CCNr;
373     }
374 
375     /**
376      * Used to sort timing relevant objects (i.e. events) into timing/scheduler
377      * queue. This class is just intended as base class and should be derived
378      * for its actual purpose (for the precise data type being scheduled).
379      */
380     class SchedulerNode : public RTAVLNode {
381     public:
382         using RTAVLNode::reset; // make reset() method public
383 
384         sched_time_t scheduleTime; ///< Time ahead in future (in sample points) when this object shall be processed. This value is compared with EventGenerator's uiTotalSamplesProcessed member variable.
385 
386         /// Required operator implementation for RTAVLTree class.
387         inline bool operator==(const SchedulerNode& other) const {
388             return this->scheduleTime == other.scheduleTime;
389         }
390 
391         /// Required operator implementation for RTAVLTree class.
392         inline bool operator<(const SchedulerNode& other) const {
393             return this->scheduleTime < other.scheduleTime;
394         }
395 
396         /// This is actually just for code readability.
currentSchedulerQueue()397         inline RTAVLTreeBase* currentSchedulerQueue() const { return rtavlTree(); }
398     };
399 
400     /**
401      * Used to sort delayed MIDI events into a timing/scheduler queue. This
402      * object just contains the timing informations, the actual MIDI event is
403      * pointed by member variable @c itEvent.
404      */
405     class ScheduledEvent : public SchedulerNode {
406     public:
407         Pool<Event>::Iterator itEvent; ///< Points to the actual Event object being scheduled.
408     };
409 
410     class VMEventHandler;
411     class VMExecContext;
412 
413     /**
414      * Maximum amount of child script handler instances one script handler is
415      * allowed to create by calling built-in script function fork().
416      */
417     #define MAX_FORK_PER_SCRIPT_HANDLER 8
418 
419     /** @brief Real-time instrument script event.
420      *
421      * Encapsulates one execution instance of a real-time instrument script for
422      * exactly one script event handler (script event callback).
423      *
424      * This class derives from SchedulerNode for being able to be sorted efficiently
425      * by the script scheduler if the script was either a) calling the wait()
426      * script function or b) the script was auto suspended by the ScriptVM
427      * because the script was executing for too long. In both cases the
428      * scheduler has to sort the ScriptEvents in its execution queue according
429      * to the precise time the respective script execution instance needs to be
430      * resumed.
431      */
432     class ScriptEvent : public SchedulerNode {
433     public:
434         Event cause; ///< Copy of original external @c Event that triggered this script event (i.e. MIDI note on event, MIDI CC event, etc.).
435         pool_element_id_t id; ///< Native representation of built-in script variable $EVENT_ID. For scripts' "note" event handler this will reflect the unique ID of the @c Note object, for all other event handlers the unique ID of the original external @c Event object that triggered this script event.
436         VMEventHandler** handlers; ///< The script's event handlers (callbacks) to be processed (NULL terminated list).
437         VMExecContext* execCtx; ///< Script's current execution state (polyphonic variables and execution stack).
438         int currentHandler; ///< Current index in 'handlers' list above.
439         int executionSlices; ///< Amount of times this script event has been executed by the ScriptVM runner class.
440         bool ignoreAllWaitCalls; ///< If true: calling any built-in wait*() script function should be ignored (this variable may be set with the 2nd argument of built-in script function stop_wait()).
441         bool releaseMatched; ///< Only for note handlers with polyphonic data: whether a corresponding release handler has already been triggered subsequently for this note handler.
442         VMEventHandlerType_t handlerType; ///< Native representation of built-in script variable $NI_CALLBACK_TYPE, reflecting the script event type of this script event.
443         script_callback_id_t parentHandlerID; ///< Only in case this script handler instance was created by calling built-in script function fork(): callback ID of the parent event handler instance which created this child. For regular event handler instances which were not created by fork(), this variable reflects 0 (which is always considered an invalid handler ID).
444         script_callback_id_t childHandlerID[MAX_FORK_PER_SCRIPT_HANDLER+1]; ///< In case built-in script function fork() was called by this script handler instance: A zero terminated ID list of all child event handler instances (note: children will not vanish from this list after they terminated).
445         bool autoAbortByParent; ///< Only if this is a child event handler created by calling fork(): if this is true then this child will automatically aborted if the parent event handler terminates.
446         int forkIndex; ///< Only for fork() calls: distinguishment feature which is 0 for parent, 1 for 1st child, 2 for 2nd child, etc.
447 
448         void forkTo(ScriptEvent* e, bool bAutoAbort) const;
449         int countChildHandlers() const;
450         void addChildHandlerID(script_callback_id_t childID);
451     };
452 
453     /**
454      * Insert given @a node into the supplied timing @a queue with a scheduled
455      * timing position given by @a fragmentPosBase and @a microseconds, where
456      * @a microseconds reflects the amount of microseconds in future from "now"
457      * where the node shall be scheduled, and @a fragmentPos identifies the
458      * sample point within the current audio fragment cycle which shall be
459      * interpreted by this method to be "now".
460      *
461      * The meaning of @a fragmentPosBase becomes more important the larger
462      * the audio fragment size, and vice versa it becomes less important the
463      * smaller the audio fragment size.
464      *
465      * @param queue - destination scheduler queue
466      * @param node - node (i.e. event) to be inserted into the queue
467      * @param fragmentPosBase - sample point in current audio fragment to be "now"
468      * @param microseconds - timing of node from "now" (in microseconds)
469      */
470     template<typename T>
scheduleAheadMicroSec(RTAVLTree<T> & queue,T & node,int32_t fragmentPosBase,uint64_t microseconds)471     void EventGenerator::scheduleAheadMicroSec(RTAVLTree<T>& queue, T& node, int32_t fragmentPosBase, uint64_t microseconds) {
472         // round up (+1) if microseconds is not zero (i.e. because 44.1 kHz and
473         // 1 us would yield in < 1 and thus would be offset == 0)
474         const sched_time_t offset =
475             (microseconds != 0LL) ?
476                 1.f + (float(uiSampleRate) * (float(microseconds) / 1000000.f))
477                 : 0.f;
478         node.scheduleTime = uiTotalSamplesProcessed + fragmentPosBase + offset;
479         queue.insert(node);
480     }
481 
482 } // namespace LinuxSampler
483 
484 #endif // __LS_EVENT_H__
485