From ee709b85c2bbdc7b7e3aedb41c19426852df565b Mon Sep 17 00:00:00 2001
From: tildearrow <tildearrow@protonmail.com>
Date: Mon, 20 Jun 2022 18:20:49 -0500
Subject: [PATCH] Namco WSG: per-channel oscilloscope

---
 src/engine/platform/namcowsg.cpp    | 13 +++++++++----
 src/engine/platform/sound/namco.cpp |  9 +++++----
 src/engine/platform/sound/namco.h   |  3 ++-
 3 files changed, 16 insertions(+), 9 deletions(-)

diff --git a/src/engine/platform/namcowsg.cpp b/src/engine/platform/namcowsg.cpp
index 1e8ff46d..43136d91 100644
--- a/src/engine/platform/namcowsg.cpp
+++ b/src/engine/platform/namcowsg.cpp
@@ -164,9 +164,6 @@ const char* DivPlatformNamcoWSG::getEffectName(unsigned char effect) {
 }
 
 void DivPlatformNamcoWSG::acquire(short* bufL, short* bufR, size_t start, size_t len) {
-  short* buf[2]={
-    bufL+start, bufR+start
-  };
   while (!writes.empty()) {
     QueuedWrite w=writes.front();
     switch (devType) {
@@ -186,7 +183,15 @@ void DivPlatformNamcoWSG::acquire(short* bufL, short* bufR, size_t start, size_t
     regPool[w.addr&0x3f]=w.val;
     writes.pop();
   }
-  namco->sound_stream_update(buf,len);
+  for (size_t h=start; h<start+len; h++) {
+    short* buf[2]={
+      bufL+h, bufR+h
+    };
+    namco->sound_stream_update(buf,1);
+    for (int i=0; i<chans; i++) {
+      oscBuf[i]->data[oscBuf[i]->needle++]=namco->m_channel_list[i].last_out*chans;
+    }
+  }
 }
 
 void DivPlatformNamcoWSG::updateWave(int ch) {
diff --git a/src/engine/platform/sound/namco.cpp b/src/engine/platform/sound/namco.cpp
index 82141301..811c34ab 100644
--- a/src/engine/platform/sound/namco.cpp
+++ b/src/engine/platform/sound/namco.cpp
@@ -172,10 +172,11 @@ void namco_audio_device::build_decoded_waveform(uint8_t *rgnbase)
 
 
 /* generate sound by oversampling */
-uint32_t namco_audio_device::namco_update_one(short* buffer, int size, const int16_t *wave, uint32_t counter, uint32_t freq)
+uint32_t namco_audio_device::namco_update_one(short* buffer, int size, const int16_t *wave, uint32_t counter, uint32_t freq, int16_t& last_out)
 {
 	for (int sampindex = 0; sampindex < size; sampindex++)
 	{
+    last_out=wave[WAVEFORM_POSITION(counter)];
 		buffer[sampindex]+=wave[WAVEFORM_POSITION(counter)];
 		counter += freq;
 	}
@@ -700,7 +701,7 @@ void namco_audio_device::sound_stream_update(short** outputs, int len)
 					const int16_t *lw = &m_waveform[lv][voice->waveform_select * 32];
 
 					/* generate sound into the buffer */
-					c = namco_update_one(lmix, len, lw, voice->counter, voice->frequency);
+					c = namco_update_one(lmix, len, lw, voice->counter, voice->frequency, voice->last_out);
 				}
 
 				/* only update if we have non-zero right volume */
@@ -709,7 +710,7 @@ void namco_audio_device::sound_stream_update(short** outputs, int len)
 					const int16_t *rw = &m_waveform[rv][voice->waveform_select * 32];
 
 					/* generate sound into the buffer */
-					c = namco_update_one(rmix, len, rw, voice->counter, voice->frequency);
+					c = namco_update_one(rmix, len, rw, voice->counter, voice->frequency, voice->last_out);
 				}
 
 				/* update the counter for this voice */
@@ -789,7 +790,7 @@ void namco_audio_device::sound_stream_update(short** outputs, int len)
 					const int16_t *w = &m_waveform[v][voice->waveform_select * 32];
 
 					/* generate sound into buffer and update the counter for this voice */
-					voice->counter = namco_update_one(buffer, len, w, voice->counter, voice->frequency);
+					voice->counter = namco_update_one(buffer, len, w, voice->counter, voice->frequency, voice->last_out);
 				}
 			}
 		}
diff --git a/src/engine/platform/sound/namco.h b/src/engine/platform/sound/namco.h
index 507eaed2..d3844abc 100644
--- a/src/engine/platform/sound/namco.h
+++ b/src/engine/platform/sound/namco.h
@@ -31,6 +31,7 @@ public:
 		uint32_t noise_counter;
 		int32_t noise_hold;
 		int32_t waveform_select;
+    int16_t last_out;
 	};
 
 	namco_audio_device(uint32_t clock);
@@ -43,7 +44,7 @@ public:
 
 	void build_decoded_waveform( uint8_t *rgnbase );
 	void update_namco_waveform(int offset, uint8_t data);
-	uint32_t namco_update_one(short* buffer, int size, const int16_t *wave, uint32_t counter, uint32_t freq);
+	uint32_t namco_update_one(short* buffer, int size, const int16_t *wave, uint32_t counter, uint32_t freq, int16_t& last_out);
 
 	/* waveform region */
 	uint8_t* m_wave_ptr;