When the fader is moved, interpolate its volume over the next frame.

[nageru] / audio_mixer.h

diff --git a/audio_mixer.h b/audio_mixer.h
index 6e7719f23313238b5bebaab70fea90e47af1c8b0..29016eb9ea7e07a68257bb8c02b6617edc4c4b6d 100644 (file)
--- a/audio_mixer.h
+++ b/audio_mixer.h
@@ -204,6 +204,7 @@ public:
        struct BusLevel {
                float current_level_dbfs[2];  // Digital peak of last frame, left and right.
                float peak_level_dbfs[2];  // Digital peak with hold, left and right.
+               float historic_peak_dbfs;
                float gain_staging_db;
                float compressor_attenuation_db;  // A positive number; 0.0 for no attenuation.
        };
@@ -237,7 +238,8 @@ private:
        void reset_alsa_mutex_held(DeviceSpec device_spec);
        std::map<DeviceSpec, DeviceInfo> get_devices_mutex_held() const;
        void update_meters(const std::vector<float> &samples);
-       void measure_bus_levels(unsigned bus_index, const std::vector<float> &left, const std::vector<float> &right, float volume);
+       void add_bus_to_master(unsigned bus_index, const std::vector<float> &samples_bus, std::vector<float> *samples_out);
+       void measure_bus_levels(unsigned bus_index, const std::vector<float> &left, const std::vector<float> &right);
        void send_audio_level_callback();
 
        unsigned num_cards;
@@ -270,9 +272,11 @@ private:
        std::atomic<float> compressor_threshold_dbfs[MAX_BUSES];
        std::atomic<bool> compressor_enabled[MAX_BUSES];
 
+       // Note: The values here are not in dB.
        struct PeakHistory {
-               float current_level = 0.0f;  // Peak of the last frame (not in dB).
-               float current_peak = 0.0f;  // Current peak of the peak meter (not in dB).
+               float current_level = 0.0f;  // Peak of the last frame.
+               float historic_peak = 0.0f;  // Highest peak since last reset; no falloff.
+               float current_peak = 0.0f;  // Current peak of the peak meter.
                float last_peak = 0.0f;
                float age_seconds = 0.0f;   // Time since "last_peak" was set.
        };
@@ -283,6 +287,7 @@ private:
 
        InputMapping input_mapping;  // Under audio_mutex.
        std::atomic<float> fader_volume_db[MAX_BUSES] {{ 0.0f }};
+       float last_fader_volume_db[MAX_BUSES] { 0.0f };  // Under audio_mutex.
 
        audio_level_callback_t audio_level_callback = nullptr;
        mutable std::mutex audio_measure_mutex;