otomatalabs/furnace
7
0
Fork 0
Code Issues Pull requests Actions Packages Projects Releases Wiki Activity

acquireDirect proof of concept

Browse source 
extremely low CPU usage in PC Speaker

WARNING! no per-chan osc yet!
This commit is contained in:
tildearrow 2025-02-25 19:58:25 -05:00
parent 4502fa6912
commit d935d3c6d1
2 changed files with 41 additions and 21 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

56
src/engine/platform/pcspkr.cpp
View file

@ -192,26 +192,39 @@ const char** DivPlatformPCSpeaker::getRegisterSheet() {
return regCheatSheetPCSpeaker;
}
void DivPlatformPCSpeaker::acquire_unfilt(short** buf, size_t len) {
void DivPlatformPCSpeaker::acquire_unfilt(blip_buffer_t** bb, size_t off, size_t len) {
int out=0;
for (size_t i=0; i<len; i++) {
if (on) {
pos-=PCSPKR_DIVIDER;
if (on) {
// just in case
out=(posToggle && !isMuted[0])?32767:0;
blip_add_delta(bb[0],off,out-oldOut);
oldOut=out;
if (freq>=1) {
if (pos>freq) pos=freq;
while (pos<0) {
if (freq<1) {
pos=1;
size_t boff=off;
size_t i=len;
while (true) {
if ((int)i<pos) {
pos-=i;
break;
}
i-=pos;
boff+=pos;
posToggle=!posToggle;
out=(posToggle && !isMuted[0])?32767:0;
blip_add_delta(bb[0],boff,out-oldOut);
oldOut=out;
if (freq&1) {
pos=(freq>>1)+(posToggle?1:0);
} else {
pos+=freq;
pos=freq>>1;
}
}
out=(pos>(freq>>1) && !isMuted[0])?32767:0;
buf[0][i]=out;
oscBuf->data[oscBuf->needle++]=out;
} else {
buf[0][i]=0;
oscBuf->data[oscBuf->needle++]=0;
}
} else {
out=0;
blip_add_delta(bb[0],off,out-oldOut);
oldOut=out;
}
}
@ -325,9 +338,6 @@ void DivPlatformPCSpeaker::acquire_real(blip_buffer_t** bb, size_t off, size_t l
void DivPlatformPCSpeaker::acquire(short** buf, size_t len) {
switch (speakerType) {
case 0:
acquire_unfilt(buf,len);
break;
case 1:
acquire_cone(buf,len);
break;
@ -339,6 +349,9 @@ void DivPlatformPCSpeaker::acquire(short** buf, size_t len) {
void DivPlatformPCSpeaker::acquireDirect(blip_buffer_t** bb, size_t off, size_t len) {
switch (speakerType) {
case 0:
acquire_unfilt(bb,off,len);
break;
case 3:
acquire_real(bb,off,len);
break;
@ -383,6 +396,7 @@ void DivPlatformPCSpeaker::tick(bool sysTick) {
}
if (freq!=chan[i].freq && resetPhase) {
pos=0;
posToggle=false;
}
freq=chan[i].freq;
if (chan[i].keyOn) chan[i].keyOn=false;
@ -544,9 +558,11 @@ void DivPlatformPCSpeaker::reset() {
freq=0;
lastFreq=0;
pos=0;
posToggle=true;
flip=false;
low=0;
band=0;
oldOut=0;
//if (speakerType==3) {
#ifdef __linux__
@ -623,9 +639,13 @@ void DivPlatformPCSpeaker::setFlags(const DivConfig& flags) {
break;
}
CHECK_CUSTOM_CLOCK;
rate=chipClock/PCSPKR_DIVIDER;
speakerType=flags.getInt("speakerType",0)&3;
resetPhase=flags.getBool("resetPhase",false);
if (speakerType==0 || speakerType==3) {
rate=chipClock;
} else {
rate=chipClock/PCSPKR_DIVIDER;
}
oscBuf->rate=rate;
switch (speakerType) {

6
src/engine/platform/pcspkr.h
View file

@ -51,8 +51,8 @@ class DivPlatformPCSpeaker: public DivDispatch {
FixedQueue<RealQueueVal,2048> realQueue;
std::mutex realQueueLock;
bool isMuted[1];
bool on, flip, lastOn, realOutEnabled, resetPhase;
int pos, speakerType, beepFD, realOutMethod;
bool on, flip, lastOn, realOutEnabled, resetPhase, posToggle;
int pos, oldOut, speakerType, beepFD, realOutMethod;
float low, band;
float low2, high2, band2;
float low3, band3;
@ -67,7 +67,7 @@ class DivPlatformPCSpeaker: public DivDispatch {
void beepFreq(int freq, int delay=0);
void acquire_unfilt(short** buf, size_t len);
void acquire_unfilt(blip_buffer_t** bb, size_t off, size_t len);
void acquire_cone(short** buf, size_t len);
void acquire_piezo(short** buf, size_t len);
void acquire_real(blip_buffer_t** bb, size_t off, size_t len);