Rocket-Flight-Simulator-Program/rocket_engine.cpp at main · karinarosot/Rocket-Flight-Simulator-Program · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
#include <iostream>
#include <cmath>
#include <pybind11/pybind11.h>

namespace py = pybind11;

class Rocket {
private:
    double height = 0.0;
    double velocity = 0.0;
    double fuel_mass = 0.0;
    double acceleration = 0.0;
    double rocket_mass = 0.0;
    double total_mass = 0.0;
    double fuel_burn_rate = 0.0;
    double exhaust_velocity = 0.0;
    double thrust = 0.0;

    double diameter = 0.0;
    double drag_coefficient = 0.3;

public:
    Rocket() = default;

    void set_parameters(double fuel_m, double rocket_m, double burn_rate,
                        double exhaust_v, double diam, double drag_c) {
        fuel_mass = fuel_m;
        rocket_mass = rocket_m;
        fuel_burn_rate = burn_rate;
        exhaust_velocity = exhaust_v;
        diameter = diam;
        drag_coefficient = drag_c;
        total_mass = rocket_mass + fuel_mass;
    }

    double get_fuel_mass() const { return fuel_mass; }
    double get_height() const { return height; }
    double get_velocity() const { return velocity; }
    double get_acceleration() const { return acceleration; }

    double air_density(double h) {
        double rho0 = 1.225;
        double H = 8500.0;
        return rho0 * std::exp(-h / H);
    }

    void update_step(double dt = 1.0) {
        // 1. Ubytek paliwa i ciąg
        if (fuel_mass > 0) {
            thrust = exhaust_velocity * fuel_burn_rate;
            fuel_mass -= fuel_burn_rate * dt;
            if (fuel_mass < 0) fuel_mass = 0;
        } else {
            thrust = 0.0;
        }
        total_mass = rocket_mass + fuel_mass;

        // 2. Aerodynamika i siły
        double radius = diameter / 2.0;
        double area = 3.14159265 * radius * radius;
        double drag = 0.5 * air_density(height) * (velocity * std::abs(velocity)) * drag_coefficient * area;

        double net_force = thrust - drag - (total_mass * 9.81);
        acceleration = net_force / total_mass;

        // 3. Całkowanie Eulera
        height += velocity * dt;
        if (height < 0.0) height = 0.0;

        velocity += acceleration * dt;
    }

    bool is_burning() const { return fuel_mass > 0; }
};

// --- SEKCKA PYBIND11 (eksport do Pythona) ---
PYBIND11_MODULE(rocket_engine, m) {
    py::class_<Rocket>(m, "Rocket")
        .def(py::init<>())
        .def("set_parameters", &Rocket::set_parameters)
        .def("update_step", &Rocket::update_step, py::arg("dt") = 1.0)
        .def("get_height", &Rocket::get_height)
        .def("get_velocity", &Rocket::get_velocity)
        .def("get_acceleration", &Rocket::get_acceleration)
        .def("get_fuel_mass", &Rocket::get_fuel_mass)
        .def("is_burning", &Rocket::is_burning);
}