diff options
Diffstat (limited to 'libs/fluidsynth/src/fluid_rvoice_mixer.c')
| -rw-r--r-- | libs/fluidsynth/src/fluid_rvoice_mixer.c | 55 |
1 files changed, 38 insertions, 17 deletions
diff --git a/libs/fluidsynth/src/fluid_rvoice_mixer.c b/libs/fluidsynth/src/fluid_rvoice_mixer.c index 5ea08ff6fa..d7fd2f541f 100644 --- a/libs/fluidsynth/src/fluid_rvoice_mixer.c +++ b/libs/fluidsynth/src/fluid_rvoice_mixer.c @@ -359,14 +359,14 @@ get_dest_buf(fluid_rvoice_buffers_t *buffers, int index, } /** - * Mix data down to buffers + * Mix samples down from internal dsp_buf to output buffers * * @param buffers Destination buffer(s) * @param dsp_buf Mono sample source - * @param start_block Block to start mixing at + * @param start_block starting sample in dsp_buf * @param sample_count number of samples to mix following \c start_block * @param dest_bufs Array of buffers to mixdown to - * @param dest_bufcount Length of dest_bufs + * @param dest_bufcount Length of dest_bufs (i.e count of buffers) */ static void fluid_rvoice_buffers_mix(fluid_rvoice_buffers_t *buffers, @@ -374,9 +374,11 @@ fluid_rvoice_buffers_mix(fluid_rvoice_buffers_t *buffers, int start_block, int sample_count, fluid_real_t **dest_bufs, int dest_bufcount) { + /* buffers count to mixdown to */ int bufcount = buffers->count; int i, dsp_i; + /* if there is nothing to mix, return immediatly */ if(sample_count <= 0 || dest_bufcount <= 0) { return; @@ -385,6 +387,7 @@ fluid_rvoice_buffers_mix(fluid_rvoice_buffers_t *buffers, FLUID_ASSERT((uintptr_t)dsp_buf % FLUID_DEFAULT_ALIGNMENT == 0); FLUID_ASSERT((uintptr_t)(&dsp_buf[start_block * FLUID_BUFSIZE]) % FLUID_DEFAULT_ALIGNMENT == 0); + /* mixdown for each buffer */ for(i = 0; i < bufcount; i++) { fluid_real_t *FLUID_RESTRICT buf = get_dest_buf(buffers, i, dest_bufs, dest_bufcount); @@ -397,11 +400,17 @@ fluid_rvoice_buffers_mix(fluid_rvoice_buffers_t *buffers, FLUID_ASSERT((uintptr_t)buf % FLUID_DEFAULT_ALIGNMENT == 0); + /* mixdown sample_count samples in the current buffer buf + Note, that this loop could be unrolled by FLUID_BUFSIZE elements */ #pragma omp simd aligned(dsp_buf,buf:FLUID_DEFAULT_ALIGNMENT) - - for(dsp_i = (start_block * FLUID_BUFSIZE); dsp_i < sample_count; dsp_i++) + for(dsp_i = 0; dsp_i < sample_count; dsp_i++) { - buf[dsp_i] += amp * dsp_buf[dsp_i]; + // Index by blocks (not by samples) to let the compiler know that we always start accessing + // buf and dsp_buf at the FLUID_BUFSIZE*sizeof(fluid_real_t) byte boundary and never somewhere + // in between. + // A good compiler should understand: Aha, so I don't need to add a peel loop when vectorizing + // this loop. Great. + buf[start_block * FLUID_BUFSIZE + dsp_i] += amp * dsp_buf[start_block * FLUID_BUFSIZE + dsp_i]; } } } @@ -416,30 +425,42 @@ fluid_mixer_buffers_render_one(fluid_mixer_buffers_t *buffers, fluid_rvoice_t *rvoice, fluid_real_t **dest_bufs, unsigned int dest_bufcount, fluid_real_t *src_buf, int blockcount) { - int i, total_samples = 0, start_block = 0; + int i, total_samples = 0, last_block_mixed = 0; for(i = 0; i < blockcount; i++) { + /* render one block in src_buf */ int s = fluid_rvoice_write(rvoice, &src_buf[FLUID_BUFSIZE * i]); - if(s == -1) { - start_block += s; - s = FLUID_BUFSIZE; - } + /* the voice is silent, mix back all the previously rendered sound */ + fluid_rvoice_buffers_mix(&rvoice->buffers, src_buf, last_block_mixed, + total_samples - (last_block_mixed*FLUID_BUFSIZE), + dest_bufs, dest_bufcount); - total_samples += s; - - if(s < FLUID_BUFSIZE) + last_block_mixed = i+1; /* future block start index to mix from */ + total_samples += FLUID_BUFSIZE; /* accumulate samples count rendered */ + } + else { - break; + /* the voice wasn't quiet. Some samples have been rendered [0..FLUID_BUFSIZE] */ + total_samples += s; + if(s < FLUID_BUFSIZE) + { + /* voice has finished */ + break; + } } } - fluid_rvoice_buffers_mix(&rvoice->buffers, src_buf, -start_block, total_samples - ((-start_block)*FLUID_BUFSIZE), dest_bufs, dest_bufcount); + /* Now mix the remaining blocks from last_block_mixed to total_sample */ + fluid_rvoice_buffers_mix(&rvoice->buffers, src_buf, last_block_mixed, + total_samples - (last_block_mixed*FLUID_BUFSIZE), + dest_bufs, dest_bufcount); if(total_samples < blockcount * FLUID_BUFSIZE) { + /* voice has finished */ fluid_finish_rvoice(buffers, rvoice); } } @@ -601,7 +622,7 @@ fluid_mixer_buffers_zero(fluid_mixer_buffers_t *buffers, int current_blockcount) static int fluid_mixer_buffers_init(fluid_mixer_buffers_t *buffers, fluid_rvoice_mixer_t *mixer) { - const int samplecount = FLUID_BUFSIZE * FLUID_MIXER_MAX_BUFFERS_DEFAULT; + static const int samplecount = FLUID_BUFSIZE * FLUID_MIXER_MAX_BUFFERS_DEFAULT; buffers->mixer = mixer; buffers->buf_count = mixer->buffers.buf_count; |