Cleanup: don't need to store _{input,output}_channels.

2 files changed, 20 insertions, 22 deletions

diff --git a/src/lib/audio_mapping.cc b/src/lib/audio_mapping.cc
index ca2425862..74b33aa35 100644
--- a/src/lib/audio_mapping.cc
+++ b/src/lib/audio_mapping.cc
@@ -61,12 +61,9 @@ AudioMapping::AudioMapping (int input_channels, int output_channels)
 void
 AudioMapping::setup (int input_channels, int output_channels)
 {
-	_input_channels = input_channels;
-	_output_channels = output_channels;
-
-	_gain.resize (_input_channels);
-	for (int i = 0; i < _input_channels; ++i) {
-		_gain[i].resize (_output_channels);
+	_gain.resize(input_channels);
+	for (int i = 0; i < input_channels; ++i) {
+		_gain[i].resize(output_channels);
 	}
 
 	make_zero ();
@@ -76,9 +73,9 @@ AudioMapping::setup (int input_channels, int output_channels)
 void
 AudioMapping::make_zero ()
 {
-	for (int i = 0; i < _input_channels; ++i) {
-		for (int j = 0; j < _output_channels; ++j) {
-			_gain[i][j] = 0;
+	for (auto& input: _gain) {
+		for (auto& output: input) {
+			output = 0;
 		}
 	}
 }
@@ -224,11 +221,14 @@ AudioMapping::get (int input_channel, int output_channel) const
 void
 AudioMapping::as_xml (xmlpp::Node* node) const
 {
-	node->add_child ("InputChannels")->add_child_text (raw_convert<string> (_input_channels));
-	node->add_child ("OutputChannels")->add_child_text (raw_convert<string> (_output_channels));
+	auto const input = input_channels();
+	auto const output = output_channels();
+
+	node->add_child("InputChannels")->add_child_text(raw_convert<string>(input));
+	node->add_child("OutputChannels")->add_child_text(raw_convert<string>(output));
 
-	for (int c = 0; c < _input_channels; ++c) {
-		for (int d = 0; d < _output_channels; ++d) {
+	for (int c = 0; c < input; ++c) {
+		for (int d = 0; d < output; ++d) {
 			auto t = node->add_child ("Gain");
 			t->set_attribute ("Input", raw_convert<string> (c));
 			t->set_attribute ("Output", raw_convert<string> (d));
@@ -245,11 +245,11 @@ string
 AudioMapping::digest () const
 {
 	Digester digester;
-	digester.add (_input_channels);
-	digester.add (_output_channels);
-	for (int i = 0; i < _input_channels; ++i) {
-		for (int j = 0; j < _output_channels; ++j) {
-			digester.add (_gain[i][j]);
+	digester.add(input_channels());
+	digester.add(output_channels());
+	for (auto const& input: _gain) {
+		for (auto output: input) {
+			digester.add(output);
 		}
 	}
 
diff --git a/src/lib/audio_mapping.h b/src/lib/audio_mapping.h
index 51ab0e1e5..0f59cc205 100644
--- a/src/lib/audio_mapping.h
+++ b/src/lib/audio_mapping.h
@@ -64,11 +64,11 @@ public:
 	float get (int input_channel, dcp::Channel output_channel) const;
 
 	int input_channels () const {
-		return _input_channels;
+		return _gain.size();
 	}
 
 	int output_channels () const {
-		return _output_channels;
+		return _gain.empty() ? 0 : _gain[0].size();
 	}
 
 	std::string digest () const;
@@ -79,8 +79,6 @@ public:
 private:
 	void setup (int input_channels, int output_channels);
 
-	int _input_channels = 0;
-	int _output_channels = 0;
 	/** Linear gains */
 	std::vector<std::vector<float>> _gain;
 };