#include "board.hpp" #include "forces.hpp" #include "math.h" #include "pedestrian.hpp" #include "tsc_x86.h" #include "vector2d.hpp" #include #define BOARD_WIDTH 10.0 #define BOARD_LENGTH 50.0 using namespace std; // Numer of pedestrians // $n_p$ // const int n_p = 100; // Number of iterations // $n_{iter}$ // const int n_iter = 100; Pedestrian *init_pedestrians(int n_p) { Pedestrian *P = new Pedestrian[n_p]; std::random_device rd; // use for truly random simulation std::mt19937 gen(rd()); // use rd instead of 42 as seed for real randomness std::normal_distribution velocity_gen(1.34, 0.26); // 1.34 and 0.26 are the mean and stdrd deviation used in paper std::uniform_real_distribution x_gen(2, BOARD_LENGTH - 2); std::uniform_real_distribution y_gen(2, BOARD_WIDTH - 2); for (int i = 0; i < n_p / 2; i++) { Vector2d start_pos = Vector2d(1, y_gen(gen)); Vector2d destination = Vector2d(BOARD_LENGTH - 1, y_gen(gen)); double desired_v0 = velocity_gen(gen); double v_max = 1.3 * desired_v0; P[i] = Pedestrian(WHITE, (destination - start_pos) / (destination - start_pos).norm() * desired_v0, start_pos, (destination - start_pos) / (destination - start_pos).norm(), v_max, desired_v0, destination, Vector2d()); } for (int i = n_p / 2; i < n_p; i++) { Vector2d start_pos = Vector2d(BOARD_LENGTH - 1, y_gen(gen)); Vector2d destination = Vector2d(1, y_gen(gen)); double desired_v0 = velocity_gen(gen); double v_max = 1.3 * desired_v0; P[i] = Pedestrian(BLACK, (destination - start_pos) / (destination - start_pos).norm() * desired_v0, start_pos, (destination - start_pos) / (destination - start_pos).norm(), v_max, desired_v0, destination, Vector2d(0, 0)); } return P; } int main(int argc, const char *argv[]) { Obstacle obs[] = {}; Board board = Board(BOARD_LENGTH, BOARD_WIDTH, 0, obs); int n_p = atoi(argv[1]); int n_iter = atoi(argv[2]); Pedestrian *pedestrians = init_pedestrians(n_p); // # Start here or right after function signature uint64_t start = start_tsc(); // # (8 + 55N - 55 + 144 + 4 + 8 + 4 + 10)*n_p*n_iter for (int t = 0; t < n_iter; t++) { // Pass1: conmpute all forces from the current state for (int i = 0; i < n_p; i++) { Pedestrian &p = pedestrians[i]; p.f_i.reset(); // # 8 flops compute_acceleration_term(&p); // # 55N - 55 flops compute_repulsive_effects_from_pedestrians(pedestrians, &p, n_p); // # 144 flops compute_repulsive_effects_from_borders(board, &p); } // Pass2: integrate the forces and update the current state for (int i = 0; i < n_p; i++) { Pedestrian &p = pedestrians[i]; // # 4 flops = 2 ADDs, 2 MULTs Vector2d w_alpha = p.curr_vel + p.f_i * dt; // # 8 flops = 2 MULTs, 2 DIVs, 1 SQRT, 2 MULTs, 1 ADD p.curr_vel = w_alpha * g(p.v_max, w_alpha.norm()); // # 4 flops = 2 ADDs, 2 MULTs p.curr_pos = p.curr_pos + p.curr_vel * dt; // # 10 flops = 5 ADDs, 2 DIVs, 1 SQRT, 2 MULTs p.e = (p.destination - p.curr_pos) / (p.destination - p.curr_pos).norm(); } } int W = (8 + 55 * n_p - 55 + 144 + 4 + 8 + 4 + 10) * n_p * n_iter; std::cout << "W(n): "; std::cout << W; std::cout << " flops\n"; double T = stop_tsc(start); std::cout << "T(n): "; std::cout << T; std::cout << " cycles\n"; double P = W / T; std::cout << "P(n): "; std::cout << P; std::cout << " flops/cycle\n"; delete[] pedestrians; return 0; }