Port FluidSim core and scenarios to C++20

include/FluidSim/HelmholtzScenario.hpp

@@ -0,0 +1,28 @@
+#pragma once
+
+#include "FluidSim\AudioProcessing.hpp"
+#include "FluidSim\Fluid.hpp"
+#include "FluidSim\Solver.hpp"
+#include <vector>
+
+namespace fluidsim::port {
+
+class HelmholtzScenario {
+public:
+    explicit HelmholtzScenario(int sample_rate = 44100);
+    float process();
+    float cavity_pressure() const { return cavity_.pressure(); }
+    float open_end_flow() const { return boundaries_.open_end_mass_flow(0); }
+    const Pipe1D& neck() const { return pipes_.front(); }
+
+private:
+    Volume0D cavity_{1e-3f, 1.1f * 101325.0f, 300.0f};
+    Port* cavity_port_{};
+    std::vector<Pipe1D> pipes_;
+    float dt_{}, neck_area_{}, cavity_orifice_area_{};
+    BoundarySystem boundaries_;
+    Solver solver_;
+    SoundProcessor sound_;
+};
+
+} // namespace fluidsim::port