more_precise_music test

tests/meson.build

@@ -11,4 +11,11 @@ executable(
     'mouse_events.cpp',
     dependencies: deps,
     include_directories: inc,
+)
+
+executable(
+    'more_precise_music',
+    'more_precise_music.cpp',
+    dependencies: deps + [dependency('openal')],
+    include_directories: inc,
 )

tests/more_precise_music.cpp

@@ -0,0 +1,53 @@
+#include "more_precise_music.hpp"
+
+#include <chrono>
+#include <iostream>
+#include <string>
+#include <thread>
+#include <vector>
+
+MorePreciseMusic::MorePreciseMusic(const std::filesystem::path& path) {
+    if (not alIsExtensionPresent("AL_SOFT_source_latency")) {
+        throw std::runtime_error("Error: AL_SOFT_source_latency not supported");
+    }
+
+    (alGetSourcedvSOFT) = reinterpret_cast<LPALGETSOURCEDVSOFT>(alGetProcAddress("alGetSourcedvSOFT"));
+
+    if (not this->openFromFile(path.string())) {
+        throw std::runtime_error("Could not open "+path.string());
+    }
+}
+
+bool MorePreciseMusic::onGetData(sf::SoundStream::Chunk& data) {
+    auto result = sf::Music::onGetData(data);
+    time_since_last_mix.restart();
+    ALdouble offsets[2];
+    alGetSourcedvSOFT(m_source, AL_SEC_OFFSET_LATENCY_SOFT, offsets);
+    open_al_playback_position_from_lag = sf::seconds(offsets[0]);
+    open_al_lag = sf::seconds(offsets[1]);
+    ALfloat secs = 0.f;
+    alGetSourcef(m_source, AL_SEC_OFFSET, &secs);
+    open_al_offset = sf::seconds(secs);
+    return result;
+}
+
+int main(int argc, char** argv) {
+    std::vector<std::string> args = {argv, argv+argc};
+    if (args.size() != 2) {
+        std::cout << "Usage : " << args[0] << " [file]" << std::endl;
+        return -1;
+    }
+
+    auto music = MorePreciseMusic{args[1]};
+    music.play();
+    std::cout << "getPlayingOffset, time_since_last_mix, open_al_playback_position_from_lag, open_al_lag, open_al_offset" << std::endl;
+    for (int i = 0; i < 5000; i++) {
+    //while (music.getStatus() == sf::Music::Playing) {
+        std::cout << music.getPlayingOffset().asMicroseconds() << ", ";
+        std::cout << music.time_since_last_mix.getElaspedTime().asMicroseconds() << ", ";
+        std::cout << music.open_al_playback_position_from_lag.asMicroseconds() << ", ";
+        std::cout << music.open_al_lag.asMicroseconds() << ", ";
+        std::cout << music.open_al_offset.asMicroseconds() << std::endl;
+        std::this_thread::sleep_for(std::chrono::milliseconds(1));
+    }
+}

tests/more_precise_music.hpp

@@ -0,0 +1,18 @@
+#include <filesystem>
+
+#include <SFML/Audio.hpp>
+
+#include "AL/al.h"
+#include "AL/alext.h"
+
+struct MorePreciseMusic : sf::Music {
+    MorePreciseMusic(const std::filesystem::path& path);
+    sf::Clock time_since_last_mix;
+    sf::Time open_al_playback_position_from_lag = sf::Time::Zero;
+    sf::Time open_al_lag = sf::Time::Zero;
+    sf::Time open_al_offset = sf::Time::Zero;
+    bool lag_measured = false;
+    LPALGETSOURCEDVSOFT alGetSourcedvSOFT;
+protected:
+    bool onGetData(sf::SoundStream::Chunk& data) override;
+};