diff options
| -rw-r--r-- | OpenAL32/Include/alMidi.h | 64 | ||||
| -rw-r--r-- | OpenAL32/alMidi.c | 97 |
2 files changed, 161 insertions, 0 deletions
diff --git a/OpenAL32/Include/alMidi.h b/OpenAL32/Include/alMidi.h new file mode 100644 index 00000000..b6504706 --- /dev/null +++ b/OpenAL32/Include/alMidi.h @@ -0,0 +1,64 @@ +#ifndef ALMIDI_H +#define ALMIDI_H + +#include "alMain.h" +#include "evtqueue.h" + +#ifdef __cplusplus +extern "C" { +#endif + +struct MidiSynthVtable; + +typedef struct MidiSynth { + EvtQueue EventQueue; + + ALuint64 LastEvtTime; + ALuint64 NextEvtTime; + ALdouble SamplesSinceLast; + ALdouble SamplesToNext; + + ALuint SampleRate; + ALdouble SamplesPerTick; + + volatile ALenum State; + + char *FontName; + + const struct MidiSynthVtable *vtbl; +} MidiSynth; + + +struct MidiSynthVtable { + void (*const Destruct)(MidiSynth *self); + + void (*const setState)(MidiSynth *self, ALenum state); + void (*const update)(MidiSynth *self, ALCdevice *device); + void (*const process)(MidiSynth *self, ALuint samples, ALfloat (*restrict DryBuffer)[BUFFERSIZE]); + + void (*const Delete)(MidiSynth *self); +}; + +#define DEFINE_MIDISYNTH_VTABLE(T) \ +DECLARE_THUNK(T, MidiSynth, void, Destruct) \ +DECLARE_THUNK1(T, MidiSynth, void, setState, ALenum) \ +DECLARE_THUNK1(T, MidiSynth, void, update, ALCdevice*) \ +DECLARE_THUNK2(T, MidiSynth, void, process, ALuint, ALfloatBUFFERSIZE*restrict) \ +DECLARE_THUNK(T, MidiSynth, void, Delete) \ + \ +static const struct MidiSynthVtable T##_MidiSynth_vtable = { \ + T##_MidiSynth_Destruct, \ + \ + T##_MidiSynth_setState, \ + T##_MidiSynth_update, \ + T##_MidiSynth_process, \ + \ + T##_MidiSynth_Delete, \ +} + + +#ifdef __cplusplus +} +#endif + +#endif /* ALMIDI_H */ diff --git a/OpenAL32/alMidi.c b/OpenAL32/alMidi.c index 773f4cac..a2f2eb12 100644 --- a/OpenAL32/alMidi.c +++ b/OpenAL32/alMidi.c @@ -5,7 +5,104 @@ #include <string.h> #include <limits.h> +#include "alMidi.h" +#include "alMain.h" +#include "alError.h" #include "evtqueue.h" +#include "rwlock.h" +#include "alu.h" + + +/* Microsecond resolution */ +#define TICKS_PER_SECOND (1000000) + +static void MidiSynth_Construct(MidiSynth *self, ALCdevice *device); +static void MidiSynth_Destruct(MidiSynth *self); +static inline void MidiSynth_setState(MidiSynth *self, ALenum state); +static inline ALuint MidiSynth_getTime(const MidiSynth *self); +static inline ALuint64 MidiSynth_getNextEvtTime(const MidiSynth *self); +static void MidiSynth_update(MidiSynth *self, ALCdevice *device); +static void MidiSynth_updateSpeed(MidiSynth *self); +static ALenum MidiSynth_insertEvent(MidiSynth *self, ALuint64 time, ALuint event, ALsizei param1, ALsizei param2); + + +static void MidiSynth_Construct(MidiSynth *self, ALCdevice *device) +{ + InitEvtQueue(&self->EventQueue); + + self->LastEvtTime = 0; + self->NextEvtTime = UINT64_MAX; + self->SamplesSinceLast = 0.0; + self->SamplesToNext = 0.0; + + self->State = AL_INITIAL; + + self->FontName = NULL; + + self->SampleRate = device->Frequency; + self->SamplesPerTick = (ALdouble)self->SampleRate / TICKS_PER_SECOND; + MidiSynth_updateSpeed(self); +} + +static void MidiSynth_Destruct(MidiSynth *self) +{ + free(self->FontName); + self->FontName = NULL; + + ResetEvtQueue(&self->EventQueue); +} + +static inline void MidiSynth_setState(MidiSynth *self, ALenum state) +{ + ExchangeInt(&self->State, state); +} + +static inline ALuint MidiSynth_getTime(const MidiSynth *self) +{ + ALuint time = self->LastEvtTime + (self->SamplesSinceLast/self->SamplesPerTick); + return clampu(time, self->LastEvtTime, self->NextEvtTime); +} + +static inline ALuint64 MidiSynth_getNextEvtTime(const MidiSynth *self) +{ + if(self->EventQueue.pos == self->EventQueue.size) + return UINT64_MAX; + return self->EventQueue.events[self->EventQueue.pos].time; +} + +static void MidiSynth_update(MidiSynth *self, ALCdevice *device) +{ + self->SampleRate = device->Frequency; + MidiSynth_updateSpeed(self); +} + +static void MidiSynth_updateSpeed(MidiSynth *self) +{ + ALdouble sampletickrate = (ALdouble)self->SampleRate / TICKS_PER_SECOND; + + self->SamplesSinceLast = self->SamplesSinceLast * sampletickrate / self->SamplesPerTick; + self->SamplesToNext = self->SamplesToNext * sampletickrate / self->SamplesPerTick; + self->SamplesPerTick = sampletickrate; +} + +static ALenum MidiSynth_insertEvent(MidiSynth *self, ALuint64 time, ALuint event, ALsizei param1, ALsizei param2) +{ + MidiEvent entry = { time, event, { param1, param2 } }; + ALenum err; + + err = InsertEvtQueue(&self->EventQueue, &entry); + if(err != AL_NO_ERROR) return err; + + if(entry.time < self->NextEvtTime) + { + self->NextEvtTime = entry.time; + + self->SamplesToNext = (self->NextEvtTime - self->LastEvtTime) * self->SamplesPerTick; + self->SamplesToNext -= self->SamplesSinceLast; + } + + return AL_NO_ERROR; +} void InitEvtQueue(EvtQueue *queue) |