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mixer: factor out mix_one_voice

This commit is contained in:
Jeff Epler 2020-01-12 10:12:42 -06:00
parent 8b61333937
commit e6869c8983
1 changed files with 82 additions and 77 deletions
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159
shared-module/audiomixer/Mixer.c
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@ -295,6 +295,87 @@ static inline uint32_t mult16signed(uint32_t val, int32_t mul) {
#endif
}
static void mix_one_voice(audiomixer_mixer_obj_t* self,
audiomixer_mixervoice_obj_t* voice, bool voices_active,
uint32_t* word_buffer, uint32_t length) {
uint32_t j = 0;
bool voice_done = voice->sample == NULL;
for (uint32_t i = 0; i < length; i++) {
if (!voice_done && j >= voice->buffer_length) {
if (!voice->more_data) {
if (voice->loop) {
audiosample_reset_buffer(voice->sample, false, 0);
} else {
voice->sample = NULL;
voice_done = true;
}
}
if (!voice_done) {
// Load another buffer
audioio_get_buffer_result_t result = audiosample_get_buffer(voice->sample, false, 0, (uint8_t**) &voice->remaining_buffer, &voice->buffer_length);
// Track length in terms of words.
voice->buffer_length /= sizeof(uint32_t);
voice->more_data = result == GET_BUFFER_MORE_DATA;
j = 0;
}
}
// First active voice gets copied over verbatim.
uint32_t sample_value;
if (voice_done) {
// Exit early if another voice already set all samples once.
if (voices_active) {
continue;
}
sample_value = 0;
if (!self->samples_signed) {
if (self->bits_per_sample == 8) {
sample_value = 0x7f7f7f7f;
} else {
sample_value = 0x7fff7fff;
}
}
} else {
sample_value = voice->remaining_buffer[j];
}
// apply the mixer level
if (!self->samples_signed) {
if (self->bits_per_sample == 8) {
sample_value = mult8unsigned(sample_value, voice->level);
} else {
sample_value = mult16unsigned(sample_value, voice->level);
}
} else {
if (self->bits_per_sample == 8) {
sample_value = mult8signed(sample_value, voice->level);
} else {
sample_value = mult16signed(sample_value, voice->level);
}
}
if (!voices_active) {
word_buffer[i] = sample_value;
} else {
if (self->bits_per_sample == 8) {
if (self->samples_signed) {
word_buffer[i] = add8signed(word_buffer[i], sample_value);
} else {
word_buffer[i] = add8unsigned(word_buffer[i], sample_value);
}
} else {
if (self->samples_signed) {
word_buffer[i] = add16signed(word_buffer[i], sample_value);
} else {
word_buffer[i] = add16unsigned(word_buffer[i], sample_value);
}
}
}
j++;
}
voice->buffer_length -= j;
voice->remaining_buffer += j;
}
audioio_get_buffer_result_t audiomixer_mixer_get_buffer(audiomixer_mixer_obj_t* self,
bool single_channel,
uint8_t channel,
@ -325,83 +406,7 @@ audioio_get_buffer_result_t audiomixer_mixer_get_buffer(audiomixer_mixer_obj_t*
for (int32_t v = 0; v < self->voice_count; v++) {
audiomixer_mixervoice_obj_t* voice = MP_OBJ_TO_PTR(self->voice[v]);
uint32_t j = 0;
bool voice_done = voice->sample == NULL;
for (uint32_t i = 0; i < self->len / sizeof(uint32_t); i++) {
if (!voice_done && j >= voice->buffer_length) {
if (!voice->more_data) {
if (voice->loop) {
audiosample_reset_buffer(voice->sample, false, 0);
} else {
voice->sample = NULL;
voice_done = true;
}
}
if (!voice_done) {
// Load another buffer
audioio_get_buffer_result_t result = audiosample_get_buffer(voice->sample, false, 0, (uint8_t**) &voice->remaining_buffer, &voice->buffer_length);
// Track length in terms of words.
voice->buffer_length /= sizeof(uint32_t);
voice->more_data = result == GET_BUFFER_MORE_DATA;
j = 0;
}
}
// First active voice gets copied over verbatim.
uint32_t sample_value;
if (voice_done) {
// Exit early if another voice already set all samples once.
if (voices_active) {
continue;
}
sample_value = 0;
if (!self->samples_signed) {
if (self->bits_per_sample == 8) {
sample_value = 0x7f7f7f7f;
} else {
sample_value = 0x7fff7fff;
}
}
} else {
sample_value = voice->remaining_buffer[j];
}
// apply the mixer level
if (!self->samples_signed) {
if (self->bits_per_sample == 8) {
sample_value = mult8unsigned(sample_value, voice->level);
} else {
sample_value = mult16unsigned(sample_value, voice->level);
}
} else {
if (self->bits_per_sample == 8) {
sample_value = mult8signed(sample_value, voice->level);
} else {
sample_value = mult16signed(sample_value, voice->level);
}
}
if (!voices_active) {
word_buffer[i] = sample_value;
} else {
if (self->bits_per_sample == 8) {
if (self->samples_signed) {
word_buffer[i] = add8signed(word_buffer[i], sample_value);
} else {
word_buffer[i] = add8unsigned(word_buffer[i], sample_value);
}
} else {
if (self->samples_signed) {
word_buffer[i] = add16signed(word_buffer[i], sample_value);
} else {
word_buffer[i] = add16unsigned(word_buffer[i], sample_value);
}
}
}
j++;
}
voice->buffer_length -= j;
voice->remaining_buffer += j;
mix_one_voice(self, voice, voices_active, word_buffer, self->len / sizeof(uint32_t));
voices_active = true;
}