Files
FluidSimCpp/include/FluidSim/OutdoorAudio.hpp
2026-10-23 18:29:51 +02:00

74 lines
3.0 KiB
C++

#pragma once
#include "FluidSim/AudioProcessing.hpp"
#include "FluidSim/OutdoorExhaustReverb.hpp"
#include <array>
#include <atomic>
#include <cstddef>
#include <vector>
namespace fluidsim::port {
enum class OutdoorScene { Dry, Field, Wall, Woodland, Tunnel };
const char *scene_name(OutdoorScene scene);
struct OutdoorAudioConfig {
Vec3 listener{1.6f, 1.0f, 2.0f};
Vec3 listener_right{1.0f, 0.0f, 0.0f};
Vec3 intake_position{-0.2f, 0.7f, 0.0f};
Vec3 exhaust_position{0.55f, 0.5f, 0.0f};
Vec3 second_exhaust_position{-0.55f, 0.5f, 0.0f};
bool dual_exhaust{};
float ear_spacing{0.18f}, sound_speed{343.0f};
float ground_y{0.0f}, wall_x{-1.5f};
float ground_reflection{0.35f}, wall_reflection{0.65f};
float pressure_gain{0.005f}; // 200 Pa per device full scale, not speaker SPL.
float monitor_cutoff_hz{6000.0f}; // Second-order acquisition/rendering filter.
};
// Static geometric direct/first-order reflection paths plus an explicitly
// approximate diffuse tail. No feedback into the fluid/combustion simulation.
class OutdoorAudio {
public:
explicit OutdoorAudio(int sample_rate = 44100, OutdoorAudioConfig config = {});
// Acoustic source inputs are ambient-density times mouth volume flow, kg/s.
// Fluid transport still uses actual donor-density mass flux independently.
AudioFrame process(float intake_mass_flow, float exhaust_mass_flow, float second_exhaust_mass_flow = 0);
void set_scene(OutdoorScene scene) { requested_scene_.store(scene, std::memory_order_relaxed); }
OutdoorScene scene() const { return requested_scene_.load(std::memory_order_relaxed); }
void set_monitor_filter(bool enabled) { monitor_filter_ = enabled; } // Set before playback/capture.
AudioFrame dry_frame() const { return last_dry_; }
AudioFrame unfiltered_frame() const { return last_raw_; }
private:
struct LowPass {
float b0{}, b1{}, b2{}, a1{}, a2{}, z1{}, z2{};
float process(float x);
};
struct Path {
std::size_t delay_left{}, delay_right{};
float fraction_left{}, fraction_right{}, gain_left{}, gain_right{}, alpha{1};
float state_left{}, state_right{};
int group{}; // direct, ground, wall, trees, tunnel
};
struct Emitter {
std::vector<float> filtered, raw;
std::vector<Path> paths;
std::size_t position{};
float previous_flow{};
LowPass filter;
};
int rate_{};
OutdoorAudioConfig config_;
std::atomic<OutdoorScene> requested_scene_{OutdoorScene::Wall};
OutdoorScene active_scene_{OutdoorScene::Wall};
bool monitor_filter_{true};
std::array<Emitter, 3> emitters_;
OutdoorExhaustReverb late_reverb_;
std::array<float, 5> weights_{1, 0, 0, 0, 0};
float scene_alpha_{}, tail_mix_{};
AudioFrame last_dry_{}, last_raw_{};
void configure_emitter(Emitter &emitter, Vec3 position);
AudioFrame render(Emitter &emitter, float flow, AudioFrame &dry, AudioFrame &raw);
};
} // namespace fluidsim::port