From 983407896c44c059fe8bf2ec1c684a48e8a991a7 Mon Sep 17 00:00:00 2001
From: Thomas Harte <thomas.harte@gmail.com>
Date: Sat, 1 Jun 2019 17:29:57 -0400
Subject: [PATCH] Ensures consistent audio pipeline.

---
 Machines/Apple/Macintosh/Audio.cpp     | 11 ++++++-----
 Machines/Apple/Macintosh/Audio.hpp     |  5 ++---
 Machines/Apple/Macintosh/Macintosh.cpp |  9 +++++++++
 3 files changed, 17 insertions(+), 8 deletions(-)

diff --git a/Machines/Apple/Macintosh/Audio.cpp b/Machines/Apple/Macintosh/Audio.cpp
index 77f806725..e319d4db6 100644
--- a/Machines/Apple/Macintosh/Audio.cpp
+++ b/Machines/Apple/Macintosh/Audio.cpp
@@ -24,7 +24,9 @@ void Audio::post_sample(uint8_t sample) {
 	const auto write_pointer = sample_queue_.write_pointer.load();
 	const auto read_pointer = sample_queue_.read_pointer.load();
 	const decltype(write_pointer) next_write_pointer = (write_pointer + 1) % sample_queue_.buffer.size();
-	if(next_write_pointer == read_pointer) return;
+	if(next_write_pointer == read_pointer) {
+		return;
+	}
 
 	sample_queue_.buffer[write_pointer] = sample;
 	sample_queue_.write_pointer.store(next_write_pointer);
@@ -64,13 +66,12 @@ void Audio::get_samples(std::size_t number_of_samples, int16_t *target) {
 	// that's something to return to.
 
 	// TODO: temporary implementation. Very inefficient. Replace.
-	while(number_of_samples--) {
-		*target = volume_multiplier_ * int16_t(sample_queue_.buffer[read_pointer] * volume_ * enabled_mask_);
-		++target;
+	for(std::size_t sample = 0; sample < number_of_samples; ++sample) {
+		target[sample] = volume_multiplier_ * int16_t(sample_queue_.buffer[read_pointer]);// * volume_ * enabled_mask_);
 		++subcycle_offset_;
 
 		if(subcycle_offset_ == sample_length) {
-//			printf("%d: %d\n", sample_queue_.buffer[read_pointer], volume_multiplier_ * sample_queue_.buffer[read_pointer] * volume_ * enabled_mask_);
+//			printf("%d: %d\n", sample_queue_.buffer[read_pointer], volume_multiplier_ * int16_t(sample_queue_.buffer[read_pointer]));
 			subcycle_offset_ = 0;
 			const unsigned int next_read_pointer = (read_pointer + 1) % sample_queue_.buffer.size();
 			if(next_read_pointer != write_pointer) {
diff --git a/Machines/Apple/Macintosh/Audio.hpp b/Machines/Apple/Macintosh/Audio.hpp
index 4f9b9ff27..f123020c7 100644
--- a/Machines/Apple/Macintosh/Audio.hpp
+++ b/Machines/Apple/Macintosh/Audio.hpp
@@ -61,7 +61,7 @@ class Audio: public ::Outputs::Speaker::SampleSource {
 		// A queue of fetched samples; read from by one thread,
 		// written to by another.
 		struct {
-			std::array<uint8_t, 2048> buffer;
+			std::array<uint8_t, 4096> buffer;
 			std::atomic<unsigned int> read_pointer, write_pointer;
 		} sample_queue_;
 
@@ -71,8 +71,7 @@ class Audio: public ::Outputs::Speaker::SampleSource {
 		int enabled_mask_ = 0;
 
 		std::int16_t volume_multiplier_ = 0;
-
-		std::size_t subcycle_offset_;
+		std::size_t subcycle_offset_ = 0;
 };
 
 }
diff --git a/Machines/Apple/Macintosh/Macintosh.cpp b/Machines/Apple/Macintosh/Macintosh.cpp
index 60e2b8082..e4bb411c0 100644
--- a/Machines/Apple/Macintosh/Macintosh.cpp
+++ b/Machines/Apple/Macintosh/Macintosh.cpp
@@ -59,6 +59,10 @@ class ConcreteMachine:
 			audio_.speaker.set_input_rate(float(CLOCK_RATE));
 		}
 
+		~ConcreteMachine() {
+			audio_.queue.flush();
+		}
+
 		void set_scan_target(Outputs::Display::ScanTarget *scan_target) override {
 			video_.set_scan_target(scan_target);
 		}
@@ -236,6 +240,7 @@ class ConcreteMachine:
 //			video_.run_for(time_since_video_update_.flush());
 
 			// As above: flush audio after video.
+			via_.flush();
 			audio_.queue.perform();
 		}
 
@@ -344,6 +349,10 @@ class ConcreteMachine:
 					audio_.time_since_update += duration;
 				}
 
+				void flush() {
+					audio_.flush();
+				}
+
 			private:
 				ConcreteMachine &machine_;
 				RealTimeClock &clock_;