Expand toggle into a full-on DAC.

Components/AudioToggle/AudioToggle.cpp

@@ -12,23 +12,28 @@
 
 using namespace Audio;
 
-Audio::Toggle::Toggle(Concurrency::AsyncTaskQueue<false> &audio_queue) :
-	audio_queue_(audio_queue) {}
+Audio::DAC::DAC(Concurrency::AsyncTaskQueue<false> &audio_queue, const int16_t max) :
+	audio_queue_(audio_queue), max_output_(max) {}
 
-void Toggle::set_sample_volume_range(const std::int16_t range) {
-	volume_ = range;
-	level_ = level_active_ ? volume_ : 0;
+void DAC::update_level() {
+	level_ = (output_ * volume_) / max_output_;
 }
 
-void Toggle::set_output(const bool enabled) {
-	if(is_enabled_ == enabled) return;
-	is_enabled_ = enabled;
-	audio_queue_.enqueue([this, enabled] {
-		level_active_ = enabled;
-		level_ = enabled ? volume_ : 0;
+void DAC::set_sample_volume_range(const std::int16_t range) {
+	volume_ = range;
+	update_level();
+}
+
+void DAC::set_output(const int16_t output) {
+	if(set_output_ == output) return;
+	set_output_ = output;
+
+	audio_queue_.enqueue([this, output] {
+		output_ = output;
+		update_level();
 	});
 }
 
-bool Toggle::get_output() const {
-	return is_enabled_;
+int16_t DAC::get_output() const {
+	return set_output_;
 }

Components/AudioToggle/AudioToggle.hpp

@@ -14,11 +14,11 @@
 namespace Audio {
 
 /*!
-	Provides a sample source that can programmatically be set to one of two values.
+	Provides a sample source that can programmatically be set to a fixed value
 */
-class Toggle: public Outputs::Speaker::BufferSource<Toggle, false> {
+class DAC: public Outputs::Speaker::BufferSource<DAC, false> {
 public:
-	Toggle(Concurrency::AsyncTaskQueue<false> &audio_queue);
+	DAC(Concurrency::AsyncTaskQueue<false> &audio_queue, int16_t max);
 
 	template <Outputs::Speaker::Action action>
 	void apply_samples(const std::size_t number_of_samples, Outputs::Speaker::MonoSample *const target) {
@@ -29,17 +29,33 @@ public:
 		return !level_;
 	}
 
-	void set_output(bool enabled);
-	bool get_output() const;
+	void set_output(int16_t);
+	int16_t get_output() const;
 
 private:
 	// Accessed on the calling thread.
-	bool is_enabled_ = false;
+	int16_t set_output_ = 0;
 	Concurrency::AsyncTaskQueue<false> &audio_queue_;
 
 	// Accessed on the audio thread.
 	int16_t level_ = 0, volume_ = 0;
-	bool level_active_ = false;
+	int16_t output_ = 0, max_output_ = 0;
+	void update_level();
+};
+
+/*!
+	Provides a 1-bit specialisation of the DAC.
+*/
+struct Toggle: public DAC {
+	Toggle(Concurrency::AsyncTaskQueue<false> &audio_queue) :
+		DAC(audio_queue, 1) {}
+
+	void set_output(const bool enabled) {
+		DAC::set_output(enabled);
+	}
+	bool get_output() const {
+		return bool(DAC::get_output());
+	}
 };
 
 }