1 files changed, 110 insertions, 0 deletions
diff --git a/src/audio.cpp b/src/audio.cpp
new file mode 100644
index 0000000..7a5934f
--- /dev/null
+++ b/src/audio.cpp
@@ -0,0 +1,110 @@
+/**
+ * @file audio.cpp
+ * Handles audio loading and playback
+ *
+ * Copyright (C) 2019 Clyne Sullivan
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "audio.hpp"
+#include "components/Player.hpp"
+
+#include <AL/alut.h>
+#include <iostream>
+
+AudioSystem::AudioSystem(void) :
+    device(nullptr, [](ALCdevice *d) { alcCloseDevice(d); }),
+    context(nullptr, [](ALCcontext *c) { alcDestroyContext(c); }) {}
+
+AudioSystem::~AudioSystem(void)
+{
+    alutExit();
+
+    // Delete context before device
+    alcMakeContextCurrent(nullptr);
+    context.reset();
+    device.reset();
+}
+
+void AudioSystem::configure([[maybe_unused]] entityx::EntityManager& entities,
+                            entityx::EventManager& events)
+{
+    events.subscribe<entityx::ComponentAddedEvent<Audio>>(*this);
+    events.subscribe<entityx::ComponentRemovedEvent<Audio>>(*this);
+
+    // Access device
+    device.reset(alcOpenDevice(nullptr));
+    if (!device)
+        return; // TODO Uh oh
+
+    // Create context
+    context.reset(alcCreateContext(device.get(), nullptr));
+    if (!alcMakeContextCurrent(context.get()))
+        return; // TODO Another uh oh
+
+    if (alutInitWithoutContext(nullptr, nullptr) != AL_TRUE)
+        return; // TODO Third uh oh
+
+    // Set up listener
+    ALfloat listenerOri[] = { 0.0f, 0.0f, -1.0f, 0.0f, 1.0f, 0.0f };
+    alListener3f(AL_POSITION, 0, 0, 0.0f);
+    alListener3f(AL_VELOCITY, 0, 0, 0);
+    alListenerfv(AL_ORIENTATION, listenerOri);
+
+    alDistanceModel(AL_LINEAR_DISTANCE); 
+}
+
+void AudioSystem::update(entityx::EntityManager& entities,
+                         [[maybe_unused]] entityx::EventManager& events,
+                         [[maybe_unused]] entityx::TimeDelta dt)
+{
+    entities.each<Player, Position>(
+        []([[maybe_unused]] entityx::Entity e,
+                   [[maybe_unused]] Player& p,
+                   Position &pos)
+        {
+            alListener3f(AL_POSITION, pos.x, pos.y, 0.0f);
+        });
+}
+
+void AudioSystem::receive(const entityx::ComponentAddedEvent<Audio>& cae)
+{
+    alGenSources(1, const_cast<ALuint*>(&cae.component->source));
+    //alGenBuffers(1, const_cast<ALuint*>(&cae.component->buffer));
+    
+    if (auto buf = alutCreateBufferFromFile(cae.component->fileName.c_str());
+        buf != AL_NONE) {
+        const_cast<Audio*>(cae.component.get())->buffer = buf;
+        alSourcei(cae.component->source, AL_BUFFER, buf);
+        // TODO Do these values need to be scaled to the world or window?
+        alSourcef(cae.component->source, AL_MAX_DISTANCE, 25);
+        alSourcef(cae.component->source, AL_REFERENCE_DISTANCE, 2);
+
+        std::cout << "Loaded audio: " << cae.component->fileName << std::endl;
+    }
+}
+
+void AudioSystem::receive(const entityx::ComponentRemovedEvent<Audio>& cae)
+{
+    alDeleteBuffers(1, &cae.component->buffer);
+    alDeleteSources(1, &cae.component->source);
+}
+
+void AudioSystem::playSound(const Position& pos, const Audio& audio)
+{
+    alSource3f(audio.source, AL_POSITION, pos.x, pos.y, 0);
+    alSourcePlay(audio.source);
+}
+