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-rw-r--r--fmdriver/ppz8.c175
1 files changed, 111 insertions, 64 deletions
diff --git a/fmdriver/ppz8.c b/fmdriver/ppz8.c
index d1afd72..1d06780 100644
--- a/fmdriver/ppz8.c
+++ b/fmdriver/ppz8.c
@@ -1,6 +1,7 @@
#include "ppz8.h"
#include "fmdriver_common.h"
#include <string.h>
+#include "ppz8-sinctable.inc"
unsigned ppz8_get_mask(const struct ppz8 *ppz8) {
return ppz8->mask;
@@ -32,51 +33,137 @@ void ppz8_init(struct ppz8 *ppz8, uint16_t srate, uint16_t mix_volume) {
channel->freq = 0;
channel->loopstartoff = -1;
channel->loopendoff = -1;
- channel->prevout[0] = 0;
- channel->prevout[1] = 0;
channel->vol = 8;
channel->pan = 5;
channel->voice = 0;
+ channel->looped = false;
leveldata_init(&channel->leveldata);
}
ppz8->srate = srate;
ppz8->totalvol = 12;
ppz8->mix_volume = mix_volume;
+ ppz8->interp = PPZ8_INTERP_SINC;
}
static uint64_t ppz8_loop(const struct ppz8_channel *channel, uint64_t ptr) {
if (channel->loopstartptr != (uint64_t)-1) {
- if (channel->loopendptr != (uint64_t)-1) {
- if (ptr >= channel->loopendptr) {
- if (channel->loopendptr == channel->loopstartptr) return (uint64_t)-1;
- uint32_t offset = (ptr - channel->loopendptr) >> 16;
- offset %= (uint32_t)((channel->loopendptr - channel->loopstartptr) >> 16);
- offset += (uint32_t)(channel->loopstartptr >> 16);
- return (ptr & ((1<<16)-1)) | (((uint64_t)offset) << 16);
- }
- } else if (ptr >= channel->endptr) {
- if (channel->endptr == channel->loopstartptr) return (uint64_t)-1;
- uint32_t offset = (ptr - channel->endptr) >> 16;
- offset %= (uint32_t)((channel->endptr - channel->loopstartptr) >> 16);
+ uint64_t loopendptr = (channel->loopendptr == (uint64_t)-1) ?
+ channel->endptr : channel->loopendptr;
+ if (ptr >= loopendptr) {
+ if (loopendptr == channel->loopstartptr) return (uint64_t)-1;
+ uint32_t offset = (ptr - loopendptr) >> 16;
+ offset %= (uint32_t)((loopendptr - channel->loopstartptr) >> 16);
offset += (uint32_t)(channel->loopstartptr >> 16);
return (ptr & ((1<<16)-1)) | (((uint64_t)offset) << 16);
}
}
- if (ptr >= channel->endptr) {
+ uint64_t limit = channel->endptr;
+ if ((channel->loopstartptr != (uint64_t)-1) &&
+ (channel->loopendptr != (uint64_t)-1) &&
+ (channel->loopendptr > channel->endptr)) {
+ limit = channel->loopendptr;
+ }
+ if (ptr >= limit) {
return (uint64_t)-1;
}
return ptr;
}
+static void ppz8_channel_get_centered_samples(
+ struct ppz8 *ppz8,
+ struct ppz8_channel *channel,
+ int16_t *obuf, int samples) {
+ struct ppz8_pcmbuf *buf = &ppz8->buf[channel->voice>>7];
+ uint32_t currind = channel->ptr >> 16;
+ for (int i = 0; i < samples; i++) {
+ int indoff = i - (samples - 1)/2;
+ uint32_t ind = currind + indoff;
+ if (indoff < 0) {
+ if ((channel->loopstartptr != (uint64_t)-1) && channel->looped) {
+ uint32_t loopendind = ((channel->loopendptr == (uint64_t)-1) ?
+ channel->endptr : channel->loopendptr) >> 16;
+ uint32_t loopperiod = loopendind - (channel->loopstartptr >> 16);
+ if (!loopperiod) {
+ ind = -1;
+ } else {
+ uint32_t loopoffset = -(ind - ((uint32_t)(channel->loopstartptr >> 16)) - loopperiod);
+ loopoffset %= loopperiod;
+ if (!loopoffset) loopoffset = loopperiod;
+ ind = (channel->loopstartptr >> 16) + loopperiod - loopoffset;
+ }
+ } else {
+ if (((uint32_t)-indoff) > currind) {
+ ind = -1;
+ }
+ }
+ } else {
+ uint32_t loopendind = (channel->loopendptr == (uint64_t)-1) ?
+ channel->endptr : channel->loopendptr;
+ if ((channel->loopstartptr != (uint64_t)-1) && (ind >= loopendind)) {
+ uint32_t loopperiod = loopendind - (channel->loopstartptr >> 16);
+ if (!loopperiod) {
+ ind = -1;
+ } else {
+ uint32_t loopoffset = ind - (channel->loopstartptr >> 16);
+ loopoffset %= loopperiod;
+ ind = (channel->loopstartptr >> 16) + loopoffset;
+ }
+ }
+ }
+ if ((ind >= (channel->endptr >> 16)) || (ind >= buf->buflen) || !buf->data) {
+ obuf[i] = 0;
+ } else {
+ obuf[i] = buf->data[ind];
+ }
+ }
+}
+
+static int32_t ppz8_channel_calc_nearest_neighbor(struct ppz8 *ppz8, struct ppz8_channel *channel) {
+ int16_t sample;
+ ppz8_channel_get_centered_samples(ppz8, channel, &sample, 1);
+ return sample;
+}
+
+static int32_t ppz8_channel_calc_linear(struct ppz8 *ppz8, struct ppz8_channel *channel) {
+ int32_t out = 0;
+ int16_t samples[2];
+ ppz8_channel_get_centered_samples(ppz8, channel, samples, 2);
+ uint16_t coeff = channel->ptr & 0xffffu;
+ out += (int32_t)samples[0] * (0x10000u - coeff);
+ out += (int32_t)samples[1] * coeff;
+ out >>= 16;
+ return out;
+}
+
+static int32_t ppz8_channel_calc_sinc(struct ppz8 *ppz8, struct ppz8_channel *channel) {
+ int16_t samples[7];
+ uint8_t frac = channel->ptr >> 8;
+ ppz8_channel_get_centered_samples(ppz8, channel, samples, 7);
+ const int16_t *sinctable = ppz8_sinctable[frac];
+ int32_t out = 0;
+ for (int i = 0; i < 7; i++) {
+ out += samples[i] * sinctable[i];
+ }
+ out >>= 15;
+ return out;
+}
+
static int32_t ppz8_channel_calc(struct ppz8 *ppz8, struct ppz8_channel *channel) {
struct ppz8_pcmbuf *buf = &ppz8->buf[channel->voice>>7];
struct ppz8_pcmvoice *voice = &buf->voice[channel->voice & 0x7f];
int32_t out = 0;
if (channel->vol) {
- uint16_t coeff = channel->ptr & 0xffffu;
- out += (int32_t)channel->prevout[0] * (0x10000u - coeff);
- out += (int32_t)channel->prevout[1] * coeff;
- out >>= 16;
+ switch (ppz8->interp) {
+ case PPZ8_INTERP_SINC:
+ out = ppz8_channel_calc_sinc(ppz8, channel);
+ break;
+ case PPZ8_INTERP_LINEAR:
+ out = ppz8_channel_calc_linear(ppz8, channel);
+ break;
+ default:
+ out = ppz8_channel_calc_nearest_neighbor(ppz8, channel);
+ break;
+ }
// volume: out * 2**((volume-15)/2)
out >>= (7 - ((channel->vol&0xf)>>1));
if (!(channel->vol&1)) {
@@ -86,45 +173,10 @@ static int32_t ppz8_channel_calc(struct ppz8 *ppz8, struct ppz8_channel *channel
}
uint64_t ptrdiff = (((uint64_t)channel->freq * voice->origfreq) << 1) / ppz8->srate;
- uint64_t oldptr = channel->ptr;
- channel->ptr += ptrdiff;
- uint32_t bufdiff = (channel->ptr>>16) - (oldptr>>16);
- if (bufdiff) {
- if (bufdiff == 1) {
- channel->prevout[0] = channel->prevout[1];
- channel->prevout[1] = 0;
- channel->ptr = ppz8_loop(channel, channel->ptr);
- if (channel->ptr != (uint64_t)-1) {
- uint32_t bufptr = channel->ptr >> 16;
- if (buf->data && bufptr < buf->buflen) {
- channel->prevout[1] = buf->data[bufptr];
- }
- } else {
- channel->playing = false;
- }
- } else {
- channel->prevout[0] = 0;
- channel->prevout[1] = 0;
- uint64_t ptr1 = ppz8_loop(channel, channel->ptr - 0x10000);
- if (ptr1 != (uint64_t)-1) {
- uint32_t bufptr = ptr1 >> 16;
- if (buf->data && bufptr < buf->buflen) {
- channel->prevout[0] = buf->data[bufptr];
- }
- channel->ptr = ppz8_loop(channel, channel->ptr);
- if (channel->ptr != (uint64_t)-1) {
- bufptr = channel->ptr >> 16;
- if (buf->data && bufptr < buf->buflen) {
- channel->prevout[1] = buf->data[bufptr];
- }
- } else {
- channel->playing = false;
- }
- } else {
- channel->playing = false;
- }
- }
- }
+ uint64_t newptr = channel->ptr + ptrdiff;
+ channel->ptr = ppz8_loop(channel, newptr);
+ if (newptr != channel->ptr) channel->looped = true;
+ if (channel->ptr == (uint64_t)-1) channel->playing = false;
return out;
}
@@ -276,13 +328,8 @@ static void ppz8_channel_play(struct ppz8 *ppz8, uint8_t ch, uint8_t v) {
: channel->ptr + (((uint64_t)(channel->loopstartoff))<<16);
channel->loopendptr = (channel->loopendoff == (uint32_t)-1) ? (uint64_t)-1
: channel->ptr + (((uint64_t)(channel->loopendoff))<<16);
- channel->prevout[0] = 0;
- channel->prevout[1] = 0;
channel->playing = true;
- uint32_t bufptr = channel->ptr >> 16;
- if (buf->data && bufptr < buf->buflen) {
- channel->prevout[1] = buf->data[bufptr];
- }
+ channel->looped = false;
}
static void ppz8_channel_stop(struct ppz8 *ppz8, uint8_t ch) {
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-22 09:34:36 +0000