nuclear@0: /*-
nuclear@0:  * Copyright (c) 2007, 2008 Edward Tomasz Napierała <trasz@FreeBSD.org>
nuclear@0:  * All rights reserved.
nuclear@0:  *
nuclear@0:  * Redistribution and use in source and binary forms, with or without
nuclear@0:  * modification, are permitted provided that the following conditions
nuclear@0:  * are met:
nuclear@0:  * 1. Redistributions of source code must retain the above copyright
nuclear@0:  *    notice, this list of conditions and the following disclaimer.
nuclear@0:  * 2. Redistributions in binary form must reproduce the above copyright
nuclear@0:  *    notice, this list of conditions and the following disclaimer in the
nuclear@0:  *    documentation and/or other materials provided with the distribution.
nuclear@0:  *
nuclear@0:  * ALTHOUGH THIS SOFTWARE IS MADE OF WIN AND SCIENCE, IT IS PROVIDED BY THE
nuclear@0:  * AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
nuclear@0:  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
nuclear@0:  * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
nuclear@0:  * THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
nuclear@0:  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
nuclear@0:  * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
nuclear@0:  * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
nuclear@0:  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
nuclear@0:  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
nuclear@0:  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
nuclear@0:  *
nuclear@0:  */
nuclear@0: 
nuclear@0: /**
nuclear@0:  * \file
nuclear@0:  *
nuclear@0:  * Tempo map related part.
nuclear@0:  *
nuclear@0:  */
nuclear@0: 
nuclear@0: #include <stdlib.h>
nuclear@0: #include <assert.h>
nuclear@0: #include <math.h>
nuclear@0: #include <string.h>
nuclear@0: #include "smf.h"
nuclear@0: #include "smf_private.h"
nuclear@0: 
nuclear@0: static double seconds_from_pulses(const smf_t *smf, int pulses);
nuclear@0: 
nuclear@0: /**
nuclear@0:  * If there is tempo starting at "pulses" already, return it.  Otherwise,
nuclear@0:  * allocate new one, fill it with values from previous one (or default ones,
nuclear@0:  * if there is no previous one) and attach it to "smf".
nuclear@0:  */
nuclear@0: static smf_tempo_t *
nuclear@0: new_tempo(smf_t *smf, int pulses)
nuclear@0: {
nuclear@0: 	smf_tempo_t *tempo, *previous_tempo = NULL;
nuclear@0: 
nuclear@0: 	if (smf->tempo_array->len > 0) {
nuclear@0: 		previous_tempo = smf_get_last_tempo(smf);
nuclear@0: 
nuclear@0: 		/* If previous tempo starts at the same time as new one, reuse it, updating in place. */
nuclear@0: 		if (previous_tempo->time_pulses == pulses)
nuclear@0: 			return (previous_tempo);
nuclear@0: 	}
nuclear@0: 
nuclear@0: 	tempo = malloc(sizeof(smf_tempo_t));
nuclear@0: 	if (tempo == NULL) {
nuclear@0: 		fg_critical("Cannot allocate smf_tempo_t.");
nuclear@0: 		return (NULL);
nuclear@0: 	}
nuclear@0: 
nuclear@0: 	tempo->time_pulses = pulses;
nuclear@0: 
nuclear@0: 	if (previous_tempo != NULL) {
nuclear@0: 		tempo->microseconds_per_quarter_note = previous_tempo->microseconds_per_quarter_note;
nuclear@0: 		tempo->numerator = previous_tempo->numerator;
nuclear@0: 		tempo->denominator = previous_tempo->denominator;
nuclear@0: 		tempo->clocks_per_click = previous_tempo->clocks_per_click;
nuclear@0: 		tempo->notes_per_note = previous_tempo->notes_per_note;
nuclear@0: 	} else {
nuclear@0: 		tempo->microseconds_per_quarter_note = 500000; /* Initial tempo is 120 BPM. */
nuclear@0: 		tempo->numerator = 4;
nuclear@0: 		tempo->denominator = 4;
nuclear@0: 		tempo->clocks_per_click = -1;
nuclear@0: 		tempo->notes_per_note = -1;
nuclear@0: 	}
nuclear@0: 
nuclear@0: 	fg_ptr_array_add(smf->tempo_array, tempo);
nuclear@0: 
nuclear@0: 	if (pulses == 0)
nuclear@0: 		tempo->time_seconds = 0.0;
nuclear@0: 	else
nuclear@0: 		tempo->time_seconds = seconds_from_pulses(smf, pulses);
nuclear@0: 
nuclear@0: 	return (tempo);
nuclear@0: }
nuclear@0: 
nuclear@0: static int
nuclear@0: add_tempo(smf_t *smf, int pulses, int tempo)
nuclear@0: {
nuclear@0: 	smf_tempo_t *smf_tempo = new_tempo(smf, pulses);
nuclear@0: 	if (smf_tempo == NULL)
nuclear@0: 		return (-1);
nuclear@0: 
nuclear@0: 	smf_tempo->microseconds_per_quarter_note = tempo;
nuclear@0: 
nuclear@0: 	return (0);
nuclear@0: }
nuclear@0: 
nuclear@0: static int
nuclear@0: add_time_signature(smf_t *smf, int pulses, int numerator, int denominator, int clocks_per_click, int notes_per_note)
nuclear@0: {
nuclear@0: 	smf_tempo_t *smf_tempo = new_tempo(smf, pulses);
nuclear@0: 	if (smf_tempo == NULL)
nuclear@0: 		return (-1);
nuclear@0: 
nuclear@0: 	smf_tempo->numerator = numerator;
nuclear@0: 	smf_tempo->denominator = denominator;
nuclear@0: 	smf_tempo->clocks_per_click = clocks_per_click;
nuclear@0: 	smf_tempo->notes_per_note = notes_per_note;
nuclear@0: 
nuclear@0: 	return (0);
nuclear@0: }
nuclear@0: 
nuclear@0: /**
nuclear@0:  * \internal
nuclear@0:  */
nuclear@0: void
nuclear@0: maybe_add_to_tempo_map(smf_event_t *event)
nuclear@0: {
nuclear@0: 	if (!smf_event_is_metadata(event))
nuclear@0: 		return;
nuclear@0: 
nuclear@0: 	assert(event->track != NULL);
nuclear@0: 	assert(event->track->smf != NULL);
nuclear@0: 	assert(event->midi_buffer_length >= 1);
nuclear@0: 
nuclear@0: 	/* Tempo Change? */
nuclear@0: 	if (event->midi_buffer[1] == 0x51) {
nuclear@0: 		int new_tempo = (event->midi_buffer[3] << 16) + (event->midi_buffer[4] << 8) + event->midi_buffer[5];
nuclear@0: 		if (new_tempo <= 0) {
nuclear@0: 			fg_critical("Ignoring invalid tempo change.");
nuclear@0: 			return;
nuclear@0: 		}
nuclear@0: 
nuclear@0: 		add_tempo(event->track->smf, event->time_pulses, new_tempo);
nuclear@0: 	}
nuclear@0: 
nuclear@0: 	/* Time Signature? */
nuclear@0: 	if (event->midi_buffer[1] == 0x58) {
nuclear@0: 		int numerator, denominator, clocks_per_click, notes_per_note;
nuclear@0: 
nuclear@0: 		if (event->midi_buffer_length < 7) {
nuclear@0: 			fg_critical("Time Signature event seems truncated.");
nuclear@0: 			return;
nuclear@0: 		}
nuclear@0: 
nuclear@0: 		numerator = event->midi_buffer[3];
nuclear@0: 		denominator = (int)pow(2, event->midi_buffer[4]);
nuclear@0: 		clocks_per_click = event->midi_buffer[5];
nuclear@0: 		notes_per_note = event->midi_buffer[6];
nuclear@0: 
nuclear@0: 		add_time_signature(event->track->smf, event->time_pulses, numerator, denominator, clocks_per_click, notes_per_note);
nuclear@0: 	}
nuclear@0: 
nuclear@0: 	return;
nuclear@0: }
nuclear@0: 
nuclear@0: /**
nuclear@0:  * \internal
nuclear@0:  *
nuclear@0:  * This is an internal function, called from smf_track_remove_event when tempo-related
nuclear@0:  * event being removed does not require recreation of tempo map, i.e. there are no events
nuclear@0:  * after that one.
nuclear@0:  */
nuclear@0: void
nuclear@0: remove_last_tempo_with_pulses(smf_t *smf, int pulses)
nuclear@0: {
nuclear@0: 	smf_tempo_t *tempo;
nuclear@0: 
nuclear@0: 	/* XXX: This is a partial workaround for the following problem: we have two tempo-related
nuclear@0: 	   events, A and B, that occur at the same time.  We remove B, then try to remove
nuclear@0: 	   A.  However, both tempo changes got coalesced in new_tempo(), so it is impossible
nuclear@0: 	   to remove B. */
nuclear@0: 	if (smf->tempo_array->len == 0)
nuclear@0: 		return;
nuclear@0: 
nuclear@0: 	tempo = smf_get_last_tempo(smf);
nuclear@0: 
nuclear@0: 	/* Workaround part two. */
nuclear@0: 	if (tempo->time_pulses != pulses)
nuclear@0: 		return;
nuclear@0: 
nuclear@0: 	memset(tempo, 0, sizeof(smf_tempo_t));
nuclear@0: 	free(tempo);
nuclear@0: 
nuclear@0: 	fg_ptr_array_remove_index(smf->tempo_array, smf->tempo_array->len - 1);
nuclear@0: }
nuclear@0: 
nuclear@0: static double
nuclear@0: seconds_from_pulses(const smf_t *smf, int pulses)
nuclear@0: {
nuclear@0: 	double seconds;
nuclear@0: 	smf_tempo_t *tempo;
nuclear@0: 
nuclear@0: 	tempo = smf_get_tempo_by_pulses(smf, pulses);
nuclear@0: 	assert(tempo);
nuclear@0: 	assert(tempo->time_pulses <= pulses);
nuclear@0: 
nuclear@0: 	seconds = tempo->time_seconds + (double)(pulses - tempo->time_pulses) *
nuclear@0: 		(tempo->microseconds_per_quarter_note / ((double)smf->ppqn * 1000000.0));
nuclear@0: 
nuclear@0: 	return (seconds);
nuclear@0: }
nuclear@0: 
nuclear@0: static int
nuclear@0: pulses_from_seconds(const smf_t *smf, double seconds)
nuclear@0: {
nuclear@0: 	int pulses = 0;
nuclear@0: 	smf_tempo_t *tempo;
nuclear@0: 
nuclear@0: 	tempo = smf_get_tempo_by_seconds(smf, seconds);
nuclear@0: 	assert(tempo);
nuclear@0: 	assert(tempo->time_seconds <= seconds);
nuclear@0: 
nuclear@0: 	pulses = tempo->time_pulses + (seconds - tempo->time_seconds) *
nuclear@0: 		((double)smf->ppqn * 1000000.0 / tempo->microseconds_per_quarter_note);
nuclear@0: 
nuclear@0: 	return (pulses);
nuclear@0: }
nuclear@0: 
nuclear@0: /**
nuclear@0:  * \internal
nuclear@0:  *
nuclear@0:  * Computes value of event->time_seconds for all events in smf.
nuclear@0:  * Warning: rewinds the smf.
nuclear@0:  */
nuclear@0: void
nuclear@0: smf_create_tempo_map_and_compute_seconds(smf_t *smf)
nuclear@0: {
nuclear@0: 	smf_event_t *event;
nuclear@0: 
nuclear@0: 	smf_rewind(smf);
nuclear@0: 	smf_init_tempo(smf);
nuclear@0: 
nuclear@0: 	for (;;) {
nuclear@0: 		event = smf_get_next_event(smf);
nuclear@0: 
nuclear@0: 		if (event == NULL)
nuclear@0: 			return;
nuclear@0: 
nuclear@0: 		maybe_add_to_tempo_map(event);
nuclear@0: 
nuclear@0: 		event->time_seconds = seconds_from_pulses(smf, event->time_pulses);
nuclear@0: 	}
nuclear@0: 
nuclear@0: 	/* Not reached. */
nuclear@0: }
nuclear@0: 
nuclear@0: smf_tempo_t *
nuclear@0: smf_get_tempo_by_number(const smf_t *smf, int number)
nuclear@0: {
nuclear@0: 	assert(number >= 0);
nuclear@0: 
nuclear@0: 	if (number >= smf->tempo_array->len)
nuclear@0: 		return (NULL);
nuclear@0: 
nuclear@0: 	return (fg_ptr_array_index(smf->tempo_array, number));
nuclear@0: }
nuclear@0: 
nuclear@0: /**
nuclear@0:  * Return last tempo (i.e. tempo with greatest time_pulses) that happens before "pulses".
nuclear@0:  */
nuclear@0: smf_tempo_t *
nuclear@0: smf_get_tempo_by_pulses(const smf_t *smf, int pulses)
nuclear@0: {
nuclear@0: 	int i;
nuclear@0: 	smf_tempo_t *tempo;
nuclear@0: 
nuclear@0: 	assert(pulses >= 0);
nuclear@0: 
nuclear@0: 	if (pulses == 0)
nuclear@0: 		return (smf_get_tempo_by_number(smf, 0));
nuclear@0: 
nuclear@0: 	assert(smf->tempo_array != NULL);
nuclear@0: 
nuclear@0: 	for (i = smf->tempo_array->len - 1; i >= 0; i--) {
nuclear@0: 		tempo = smf_get_tempo_by_number(smf, i);
nuclear@0: 
nuclear@0: 		assert(tempo);
nuclear@0: 		if (tempo->time_pulses < pulses)
nuclear@0: 			return (tempo);
nuclear@0: 	}
nuclear@0: 
nuclear@0: 	return (NULL);
nuclear@0: }
nuclear@0: 
nuclear@0: /**
nuclear@0:  * Return last tempo (i.e. tempo with greatest time_seconds) that happens before "seconds".
nuclear@0:  */
nuclear@0: smf_tempo_t *
nuclear@0: smf_get_tempo_by_seconds(const smf_t *smf, double seconds)
nuclear@0: {
nuclear@0: 	int i;
nuclear@0: 	smf_tempo_t *tempo;
nuclear@0: 
nuclear@0: 	assert(seconds >= 0.0);
nuclear@0: 
nuclear@0: 	if (seconds == 0.0)
nuclear@0: 		return (smf_get_tempo_by_number(smf, 0));
nuclear@0: 
nuclear@0: 	assert(smf->tempo_array != NULL);
nuclear@0: 
nuclear@0: 	for (i = smf->tempo_array->len - 1; i >= 0; i--) {
nuclear@0: 		tempo = smf_get_tempo_by_number(smf, i);
nuclear@0: 
nuclear@0: 		assert(tempo);
nuclear@0: 		if (tempo->time_seconds < seconds)
nuclear@0: 			return (tempo);
nuclear@0: 	}
nuclear@0: 
nuclear@0: 	return (NULL);
nuclear@0: }
nuclear@0: 
nuclear@0: 
nuclear@0: /**
nuclear@0:  * Return last tempo.
nuclear@0:  */
nuclear@0: smf_tempo_t *
nuclear@0: smf_get_last_tempo(const smf_t *smf)
nuclear@0: {
nuclear@0: 	smf_tempo_t *tempo;
nuclear@0: 
nuclear@0: 	tempo = smf_get_tempo_by_number(smf, smf->tempo_array->len - 1);
nuclear@0: 	assert(tempo);
nuclear@0: 
nuclear@0: 	return (tempo);
nuclear@0: }
nuclear@0: 
nuclear@0: /**
nuclear@0:  * \internal 
nuclear@0:  *
nuclear@0:  * Remove all smf_tempo_t structures from SMF.
nuclear@0:  */
nuclear@0: void
nuclear@0: smf_fini_tempo(smf_t *smf)
nuclear@0: {
nuclear@0: 	smf_tempo_t *tempo;
nuclear@0: 
nuclear@0: 	while (smf->tempo_array->len > 0) {
nuclear@0: 		tempo = fg_ptr_array_index(smf->tempo_array, smf->tempo_array->len - 1);
nuclear@0: 		assert(tempo);
nuclear@0: 
nuclear@0: 		memset(tempo, 0, sizeof(smf_tempo_t));
nuclear@0: 		free(tempo);
nuclear@0: 
nuclear@0: 		fg_ptr_array_remove_index(smf->tempo_array, smf->tempo_array->len - 1);
nuclear@0: 	}
nuclear@0: 
nuclear@0: 	assert(smf->tempo_array->len == 0);
nuclear@0: }
nuclear@0: 
nuclear@0: /**
nuclear@0:  * \internal
nuclear@0:  *
nuclear@0:  * Remove any existing tempos and add default one.
nuclear@0:  *
nuclear@0:  * \bug This will abort (by calling fg_error) if new_tempo() (memory allocation there) fails.
nuclear@0:  */
nuclear@0: void
nuclear@0: smf_init_tempo(smf_t *smf)
nuclear@0: {
nuclear@0: 	smf_tempo_t *tempo;
nuclear@0: 
nuclear@0: 	smf_fini_tempo(smf);
nuclear@0: 
nuclear@0: 	tempo = new_tempo(smf, 0);
nuclear@0: 	if (tempo == NULL)
nuclear@0: 		fg_error("tempo_init failed, sorry.");
nuclear@0: }
nuclear@0: 
nuclear@0: /**
nuclear@0:  * Returns ->time_pulses of last event on the given track, or 0, if track is empty.
nuclear@0:  */
nuclear@0: static int
nuclear@0: last_event_pulses(const smf_track_t *track)
nuclear@0: {
nuclear@0: 	/* Get time of last event on this track. */
nuclear@0: 	if (track->number_of_events > 0) {
nuclear@0: 		smf_event_t *previous_event = smf_track_get_last_event(track);
nuclear@0: 		assert(previous_event);
nuclear@0: 		assert(previous_event->time_pulses >= 0);
nuclear@0: 
nuclear@0: 		return (previous_event->time_pulses);
nuclear@0: 	}
nuclear@0: 
nuclear@0: 	return (0);
nuclear@0: }
nuclear@0: 
nuclear@0: /**
nuclear@0:  * Adds event to the track at the time "pulses" clocks from the previous event in this track.
nuclear@0:  * The remaining two time fields will be computed automatically based on the third argument
nuclear@0:  * and current tempo map.  Note that ->delta_pulses is computed by smf.c:smf_track_add_event,
nuclear@0:  * not here.
nuclear@0:  */
nuclear@0: void
nuclear@0: smf_track_add_event_delta_pulses(smf_track_t *track, smf_event_t *event, int delta)
nuclear@0: {
nuclear@0: 	assert(delta >= 0);
nuclear@0: 	assert(event->time_pulses == -1);
nuclear@0: 	assert(event->time_seconds == -1.0);
nuclear@0: 	assert(track->smf != NULL);
nuclear@0: 
nuclear@0: 	smf_track_add_event_pulses(track, event, last_event_pulses(track) + delta);
nuclear@0: }
nuclear@0: 
nuclear@0: /**
nuclear@0:  * Adds event to the track at the time "pulses" clocks from the start of song.
nuclear@0:  * The remaining two time fields will be computed automatically based on the third argument
nuclear@0:  * and current tempo map.
nuclear@0:  */
nuclear@0: void
nuclear@0: smf_track_add_event_pulses(smf_track_t *track, smf_event_t *event, int pulses)
nuclear@0: {
nuclear@0: 	assert(pulses >= 0);
nuclear@0: 	assert(event->time_pulses == -1);
nuclear@0: 	assert(event->time_seconds == -1.0);
nuclear@0: 	assert(track->smf != NULL);
nuclear@0: 
nuclear@0: 	event->time_pulses = pulses;
nuclear@0: 	event->time_seconds = seconds_from_pulses(track->smf, pulses);
nuclear@0: 	smf_track_add_event(track, event);
nuclear@0: }
nuclear@0: 
nuclear@0: /**
nuclear@0:  * Adds event to the track at the time "seconds" seconds from the start of song.
nuclear@0:  * The remaining two time fields will be computed automatically based on the third argument
nuclear@0:  * and current tempo map.
nuclear@0:  */
nuclear@0: void
nuclear@0: smf_track_add_event_seconds(smf_track_t *track, smf_event_t *event, double seconds)
nuclear@0: {
nuclear@0: 	assert(seconds >= 0.0);
nuclear@0: 	assert(event->time_pulses == -1);
nuclear@0: 	assert(event->time_seconds == -1.0);
nuclear@0: 	assert(track->smf != NULL);
nuclear@0: 
nuclear@0: 	event->time_seconds = seconds;
nuclear@0: 	event->time_pulses = pulses_from_seconds(track->smf, seconds);
nuclear@0: 	smf_track_add_event(track, event);
nuclear@0: }
nuclear@0: