From c3d4d0ee38abcec553202a39211a7b95698578bb Mon Sep 17 00:00:00 2001
From: Thomas Harte <thomas.harte@gmail.com>
Date: Tue, 16 Apr 2024 21:56:34 -0400
Subject: [PATCH] Introduce panning, threading.
---
Machines/Acorn/Archimedes/Sound.hpp | 31 ++++++++++++++++++++---------
1 file changed, 22 insertions(+), 9 deletions(-)
diff --git a/Machines/Acorn/Archimedes/Sound.hpp b/Machines/Acorn/Archimedes/Sound.hpp
index 6758719cc..417ed278f 100644
--- a/Machines/Acorn/Archimedes/Sound.hpp
+++ b/Machines/Acorn/Archimedes/Sound.hpp
@@ -109,10 +109,10 @@ struct Sound: private SoundLevels {
divider_ = reload_;
// Grab a single byte from the FIFO.
- const uint8_t raw = ram_[static_cast<std::size_t>(current_.start + byte_)];
+ const uint8_t raw = ram_[static_cast<std::size_t>(current_.start) + static_cast<std::size_t>(byte_)];
sample_ = Outputs::Speaker::StereoSample( // TODO: pan, volume.
- levels[raw],
- levels[raw]
+ static_cast<int16_t>((levels[raw] * positions_[byte_ & 7].left) / 6),
+ static_cast<int16_t>((levels[raw] * positions_[byte_ & 7].right) / 6)
);
++byte_;
@@ -137,6 +137,10 @@ struct Sound: private SoundLevels {
return &speaker_;
}
+ ~Sound() {
+ while(is_posting_.test_and_set());
+ }
+
private:
const uint8_t *ram_ = nullptr;
@@ -174,18 +178,27 @@ private:
Outputs::Speaker::PushLowpass<true> speaker_;
Concurrency::AsyncTaskQueue<true> queue_;
- // TODO: thread this stuff up properly.
void post_sample(Outputs::Speaker::StereoSample sample) {
- (void)sample;
- samples_[sample_pointer_++] = Outputs::Speaker::StereoSample(sample_pointer_ & 512 ? 32767 : 0, 0);
- if(sample_pointer_ == samples_.size()) {
- speaker_.push(reinterpret_cast<int16_t *>(samples_.data()), samples_.size());
+ samples_[sample_target_][sample_pointer_++] = sample;
+ if(sample_pointer_ == samples_[0].size()) {
+ while(is_posting_.test_and_set());
+
+ const auto post_source = sample_target_;
+ sample_target_ ^= 1;
sample_pointer_ = 0;
+ queue_.enqueue([this, post_source]() {
+ speaker_.push(reinterpret_cast<int16_t *>(samples_[post_source].data()), samples_[post_source].size());
+ is_posting_.clear();
+ });
}
}
std::size_t sample_pointer_ = 0;
- std::array<Outputs::Speaker::StereoSample, 1024> samples_;
+ std::size_t sample_target_ = 0;
Outputs::Speaker::StereoSample sample_;
+
+ using SampleBuffer = std::array<Outputs::Speaker::StereoSample, 4096>;
+ std::array<SampleBuffer, 2> samples_;
+ std::atomic_flag is_posting_ = ATOMIC_FLAG_INIT;
};
}