VRC6: acquireDirect()

to-do: check for regressions? I need to sleep

extern/vgsound_emu-modified/vgsound_emu/src/vrcvi/vrcvi.cpp

@@ -8,15 +8,27 @@
 
 #include "vrcvi.hpp"
 
-void vrcvi_core::tick()
+int vrcvi_core::predict() {
+  const int p0=m_pulse[0].predict();
+  const int p1=m_pulse[1].predict();
+  const int s=m_sawtooth.predict();
+
+  int ret=p0;
+  if (p1<ret) ret=p1;
+  if (s<ret) ret=s;
+  if (ret<1) ret=1;
+  return ret;
+}
+
+void vrcvi_core::tick(int cycles)
 {
 	m_out = 0;
 	if (!m_control.m_halt)	// Halt flag
 	{
 		// tick per each clock
-		m_out += m_pulse[0].get_output();	 // add 4 bit pulse output
+		m_out += m_pulse[0].get_output(cycles);	 // add 4 bit pulse output
-    m_out += m_pulse[1].get_output();
+    m_out += m_pulse[1].get_output(cycles);
-		m_out += m_sawtooth.get_output();  // add 5 bit sawtooth output
+		m_out += m_sawtooth.get_output(cycles);  // add 5 bit sawtooth output
 	}
 }
 
@@ -30,7 +42,18 @@ void vrcvi_core::reset()
 	m_out = 0;
 }
 
-bool vrcvi_core::alu_t::tick()
+int vrcvi_core::alu_t::predict() {
+  if (!m_divider.m_enable) return 65535;
+  if (m_host.m_control.m_shift&2) {
+    return bitfield(m_counter, 8, 4);
+  } else if (m_host.m_control.m_shift&1) {
+    return bitfield(m_counter, 4, 8);
+  }
+
+  return m_counter&0xfff;
+}
+
+bool vrcvi_core::alu_t::tick(int cycles)
 {
 	if (m_divider.m_enable)
 	{
@@ -38,8 +61,8 @@ bool vrcvi_core::alu_t::tick()
 		// post decrement
 		if (m_host.m_control.m_shift&2)
 		{
-			m_counter = (m_counter & 0x0ff) | (bitfield(bitfield(m_counter, 8, 4) - 1, 0, 4) << 8);
+			m_counter = (m_counter & 0x0ff) | (bitfield(bitfield(m_counter, 8, 4) - cycles, 0, 4) << 8);
-			m_counter = (m_counter & 0xf00) | (bitfield(bitfield(m_counter, 0, 8) - 1, 0, 8) << 0);
+			m_counter = (m_counter & 0xf00) | (bitfield(bitfield(m_counter, 0, 8) - cycles, 0, 8) << 0);
 
       if (bitfield(temp, 8, 4) == 0)
       {
@@ -49,8 +72,8 @@ bool vrcvi_core::alu_t::tick()
 		}
 		else if (m_host.m_control.m_shift&1)
 		{
-			m_counter = (m_counter & 0x00f) | (bitfield(bitfield(m_counter, 4, 8) - 1, 0, 8) << 4);
+			m_counter = (m_counter & 0x00f) | (bitfield(bitfield(m_counter, 4, 8) - cycles, 0, 8) << 4);
-			m_counter = (m_counter & 0xff0) | (bitfield(bitfield(m_counter, 0, 4) - 1, 0, 4) << 0);
+			m_counter = (m_counter & 0xff0) | (bitfield(bitfield(m_counter, 0, 4) - cycles, 0, 4) << 0);
 
       if (bitfield(temp, 4, 8) == 0)
       {
@@ -60,7 +83,7 @@ bool vrcvi_core::alu_t::tick()
 		}
 		else
 		{
-			m_counter = (m_counter-1)&0xfff; //bitfield(bitfield(m_counter, 0, 12) - 1, 0, 12);
+			m_counter = (m_counter-cycles)&0xfff; //bitfield(bitfield(m_counter, 0, 12) - 1, 0, 12);
       if (!(temp&0xfff)) {
         m_counter = m_divider.m_divider;
         return true;
@@ -72,14 +95,14 @@ bool vrcvi_core::alu_t::tick()
 	return false;
 }
 
-bool vrcvi_core::pulse_t::tick()
+bool vrcvi_core::pulse_t::tick(int cycles)
 {
 	if (!m_divider.m_enable)
 	{
 		return false;
 	}
 
-	if (vrcvi_core::alu_t::tick())
+	if (vrcvi_core::alu_t::tick(cycles))
 	{
 		m_cycle = (m_cycle+1)&15;
 	}
@@ -87,14 +110,14 @@ bool vrcvi_core::pulse_t::tick()
 	return m_control.m_mode ? true : ((m_cycle > m_control.m_duty) ? true : false);
 }
 
-bool vrcvi_core::sawtooth_t::tick()
+bool vrcvi_core::sawtooth_t::tick(int cycles)
 {
 	if (!m_divider.m_enable)
 	{
 		return false;
 	}
 
-	if (vrcvi_core::alu_t::tick())
+	if (vrcvi_core::alu_t::tick(cycles))
 	{
 		if ((m_cycle++)&1)
 		{  // Even step only
@@ -109,23 +132,24 @@ bool vrcvi_core::sawtooth_t::tick()
 	return (m_accum != 0);
 }
 
-s8 vrcvi_core::pulse_t::get_output()
+s8 vrcvi_core::pulse_t::get_output(int cycles)
 {
 	// add 4 bit pulse output
-	m_out = tick() ? m_control.m_volume : 0;
+	m_out = tick(cycles) ? m_control.m_volume : 0;
 	return m_out;
 }
 
-s8 vrcvi_core::sawtooth_t::get_output()
+s8 vrcvi_core::sawtooth_t::get_output(int cycles)
 {
 	// add 5 bit sawtooth output
-	m_out = tick() ? ((m_accum>>3)&31) : 0;
+	m_out = tick(cycles) ? ((m_accum>>3)&31) : 0;
 	return m_out;
 }
 
 void vrcvi_core::alu_t::reset()
 {
 	m_divider.reset();
+        m_divider.m_divider = 1023;
 	m_counter = 0;
 	m_cycle	  = 0;
 	m_out	  = 0;
@@ -135,6 +159,7 @@ void vrcvi_core::pulse_t::reset()
 {
 	vrcvi_core::alu_t::reset();
 	m_control.reset();
+        m_divider.m_divider = 1023;
 }
 
 void vrcvi_core::sawtooth_t::reset()
@@ -142,6 +167,7 @@ void vrcvi_core::sawtooth_t::reset()
 	vrcvi_core::alu_t::reset();
 	m_rate	= 0;
 	m_accum = 0;
+        m_divider.m_divider = 1023;
 }
 
 bool vrcvi_core::timer_t::tick()

extern/vgsound_emu-modified/vgsound_emu/src/vrcvi/vrcvi.hpp

@@ -47,7 +47,7 @@ class vrcvi_core : public vgsound_emu_core
 
 						void reset()
 						{
-							m_divider = 0;
+							m_divider = 1023;
 							m_enable  = 0;
 						}
 
@@ -75,9 +75,10 @@ class vrcvi_core : public vgsound_emu_core
 				}
 
 				virtual void reset();
-				virtual bool tick();
+				virtual bool tick(int cycles);
+				virtual int predict();
 
-				virtual s8 get_output()
+				virtual s8 get_output(int cycles)
 				{
 					m_out = 0;
 					return 0;
@@ -155,8 +156,8 @@ class vrcvi_core : public vgsound_emu_core
 				}
 
 				virtual void reset() override;
-				virtual bool tick() override;
+				virtual bool tick(int cycles) override;
-				virtual s8 get_output() override;
+				virtual s8 get_output(int cycles) override;
 
 				// getters
 				pulse_control_t &control() { return m_control; }
@@ -177,8 +178,8 @@ class vrcvi_core : public vgsound_emu_core
 				}
 
 				virtual void reset() override;
-				virtual bool tick() override;
+				virtual bool tick(int cycles) override;
-				virtual s8 get_output() override;
+				virtual s8 get_output(int cycles) override;
 
 				// accessors
 				inline void clear_accum() { m_accum = 0; }
@@ -385,7 +386,8 @@ class vrcvi_core : public vgsound_emu_core
 
 		// internal state
 		void reset();
-		void tick();
+		int predict();
+		void tick(int cycles=1);
 
 		// 6 bit output
 		inline s8 out() { return m_out; }

src/engine/platform/vrc6.cpp

@@ -46,16 +46,28 @@ const char** DivPlatformVRC6::getRegisterSheet() {
   return regCheatSheetVRC6;
 }
 
-void DivPlatformVRC6::acquire(short** buf, size_t len) {
+void DivPlatformVRC6::acquireDirect(blip_buffer_t** bb, size_t len) {
   for (int i=0; i<3; i++) {
     oscBuf[i]->begin(len);
   }
 
   for (size_t h=0; h<len; h++) {
+    // running heuristic
+    int advance=vrc6.predict();
+    if ((int)(len-h)<advance) advance=len-h;
+    for (int i=0; i<2; i++) {
+      if (chan[i].pcm && chan[i].dacSample!=-1) {
+        if (chan[i].dacRate<=0) continue;
+        int remainTime=(rate-chan[i].dacPeriod+chan[i].dacRate-1)/chan[i].dacRate;
+        if (remainTime<advance) advance=remainTime;
+        if (remainTime<1) advance=1;
+      }
+    }
+    
     // PCM part
     for (int i=0; i<2; i++) {
       if (chan[i].pcm && chan[i].dacSample!=-1) {
-        chan[i].dacPeriod+=chan[i].dacRate;
+        chan[i].dacPeriod+=chan[i].dacRate*advance;
         if (chan[i].dacPeriod>rate) {
           DivSample* s=parent->getSample(chan[i].dacSample);
           if (s->samples<=0 || chan[i].dacPos>=s->samples) {
@@ -81,11 +93,13 @@ void DivPlatformVRC6::acquire(short** buf, size_t len) {
     }
 
     // VRC6 part
-    vrc6.tick();
+    vrc6.tick(advance);
+    h+=advance-1;
     int sample=vrc6.out()<<9; // scale to 16 bit
-    if (sample>32767) sample=32767;
+    if (sample!=prevSample) {
-    if (sample<-32768) sample=-32768;
+      blip_add_delta(bb[0],h,sample-prevSample);
-    buf[0][h]=sample;
+      prevSample=sample;
+    }
 
     // Oscilloscope buffer part
     if (++writeOscBuf>=32) {
@@ -96,7 +110,7 @@ void DivPlatformVRC6::acquire(short** buf, size_t len) {
       oscBuf[2]->putSample(h,vrc6.sawtooth_out()<<10);
     }
 
-    // Command part
+    // Command part (what the heck why at the END?!)
     while (!writes.empty()) {
       QueuedWrite w=writes.front();
       switch (w.addr&0xf000) {
@@ -523,6 +537,7 @@ void DivPlatformVRC6::reset() {
   }
 
   sampleBank=0;
+  prevSample=0;
 
   vrc6.reset();
   // Initialize control register
@@ -537,6 +552,10 @@ bool DivPlatformVRC6::keyOffAffectsArp(int ch) {
   return true;
 }
 
+bool DivPlatformVRC6::hasAcquireDirect() {
+  return true;
+}
+
 void DivPlatformVRC6::setFlags(const DivConfig& flags) {
   int clockSel=flags.getInt("clockSel",0);
   if (clockSel==2) { // Dendy

src/engine/platform/vrc6.h

@@ -57,13 +57,14 @@ class DivPlatformVRC6: public DivDispatch, public vrcvi_intf {
   unsigned char sampleBank;
   unsigned char writeOscBuf;
   vrcvi_core vrc6;
+  int prevSample;
   unsigned char regPool[13];
 
   friend void putDispatchChip(void*,int);
   friend void putDispatchChan(void*,int,int);
 
   public:
-    void acquire(short** buf, size_t len);
+    void acquireDirect(blip_buffer_t** bb, size_t len);
     int dispatch(DivCommand c);
     void* getChanState(int chan);
     DivMacroInt* getChanMacroInt(int ch);
@@ -76,6 +77,7 @@ class DivPlatformVRC6: public DivDispatch, public vrcvi_intf {
     void tick(bool sysTick=true);
     void muteChannel(int ch, bool mute);
     bool keyOffAffectsArp(int ch);
+    bool hasAcquireDirect();
     void setFlags(const DivConfig& flags);
     void notifyInsDeletion(void* ins);
     void poke(unsigned int addr, unsigned short val);