diff --git a/forces.cpp b/forces.cpp index 5911909..30d4f18 100644 --- a/forces.cpp +++ b/forces.cpp @@ -27,6 +27,9 @@ void compute_acceleration_term(Pedestrian *p) { } // # 55(N - 1) = 55N - 55 flops +// +// $\sum_{\beta} \vec{F}_{\alpha\beta}(\vec{e}_{\alpha}, \vec{r}_{\alpha} - \vec{r}_{\beta})$ +// void compute_repulsive_effects_from_pedestrians(Pedestrian *pedestrians, Pedestrian *p, int N) { for (int i = 0; i < N; i++) { @@ -41,38 +44,56 @@ void compute_repulsive_effects_from_pedestrians(Pedestrian *pedestrians, Pedestr // } // # 2 ADDs + // $\vec{r}_{\alpha\beta}$ Vector2d r_ab = p->curr_pos - pedestrians[i].curr_pos; // # 4 flops = 1 SQRT, 2 MULTs, 1 ADD + // $\Arrowvert \vec{r}_{\alpha \beta} \Arrowvert$ double r_ab_norm = r_ab.norm(); + // $\vec{e}_{\beta}$ Vector2d e_b = pedestrians[i].e; // # 2 MULTs - double s_b = pedestrians[i].desired_v0 * delta_t; + // $v_\beta \Delta t$ + double s_b = pedestrians[i].curr_vel.norm() * delta_t; // # 4 flops = 2 ADDs, 2 MULTs + // $\vec{r}_{\alpha\beta} - \vec{v}_{\beta}\varDelta_{t}\vec{e}_{\beta}$ Vector2d r_ab2 = r_ab - (e_b * s_b); // # 4 flops = 1 SQRT, 2 MULTs, 1 ADD + // $\Arrowvert \vec{r}_{\alpha \beta} - v_\beta \Delta t \vec{e}_\beta \Arrowvert$ double r_ab2_norm = r_ab2.norm(); // # 7 flops = 1 SQRT, 3 ADDs, 2 MULTs, 1 DIV + // + // $(4):2b = \sqrt{(\Arrowvert \vec{r}_{\alpha \beta} \Arrowvert + \Arrowvert \vec{r}_{\alpha \beta} - v_\beta \Delta t \vec{e}_\beta \Arrowvert)^2 - (v_\beta \Delta t)^2}$ + // double b = sqrt((r_ab_norm + r_ab2_norm) * (r_ab_norm + r_ab2_norm) - s_b * s_b) / 2; // # 12 flops = 6 DIVs, 3 ADDs, 3 MULTs + // + // $(7):\grad_{\vec{r}_{\alpha \beta}}b = \frac{(\Arrowvert \vec{r}_{\alpha \beta} \Arrowvert + \Arrowvert \vec{r}_{\alpha \beta} - v_\beta \Delta t \vec{e}_\beta \Arrowvert) (\frac{\vec{r}_{\alpha \beta}}{\Arrowvert \vec{r}_{\alpha \beta} \Arrowvert} + \frac{\vec{r}_{\alpha \beta} - v_\beta \Delta t \vec{e}_\beta}{\Arrowvert \vec{r}_{\alpha \beta} - v_\beta \Delta t \vec{e}_\beta \Arrowvert})}{4b}$ + // Vector2d b_grad = (r_ab / r_ab_norm + r_ab2 / r_ab2_norm) * (r_ab_norm + r_ab2_norm) / (4 * b); // # 6 flops = 3 MULTs, 2 DIVs, 1 EXP + // + // $(5):\vec{f}_{\alpha \beta}(\vec{r}_{\alpha \beta}) = \frac{V^0_{\alpha \beta}}{\sigma}e^{-b / \sigma} \grad_{\vec{r}_{\alpha \beta}}b$ + // Vector2d f_ped = b_grad * ((V0_AB / SIGMA) * (exp(-b / SIGMA))); // # 14 flops: 9 MULTs, 4 ADDs, 1 SQRT + // + // $(11):\vec{F}_{\alpha\beta}(\vec{e}_{\alpha}, \vec{r}_{\alpha} - \vec{r}_{\beta}) = w(\vec{e}_{\alpha}, -\vec{f}_{\alpha\beta})\vec{f}_{\alpha\beta}(\vec{r}_{\alpha} - \vec{r}_{\beta})$ + // p->f_i += f_ped * w(p->e, f_ped * -1); } } // # Assume that the four borders are also 4 obstacles -// # 36 n_obstacles flops = 144 flops +// # 48 n_obstacles flops = 192 flops void compute_repulsive_effects_from_borders(Board &board, Pedestrian *p) { Obstacle *obstacles = board.obstacles; @@ -83,12 +104,25 @@ void compute_repulsive_effects_from_borders(Board &board, Pedestrian *p) { Obstacle obstacle = obstacles[i]; // # 17 flops + // $\vec{r}_{\alpha B}$ Vector2d r_aB = p->curr_pos - obstacle.find_nearest_obstacle_point(p->curr_pos); // # 17 flops = 2 DIVs, 1 SQRT, 2 MULTs, 1 ADD, 2 MULTs, 1 DIV, 2 MULTs, 1 EXP, 1 SQRT, 2 MULTs, 1 ADD, 1 DIV + // + // $\vec{F}_{\alpha B}(\vec{r}_{\alpha B}) = \frac{U^0_{\alpha B}}{R} e^{- \Arrowvert \vec{r}_{\alpha B} \Arrowvert / R} \frac{\vec{r}_{\alpha B}}{\Arrowvert \vec{r}_{\alpha B} \Arrowvert}$ + // Vector2d f_obst = (r_aB / r_aB.norm()) * (U0_AB / R) * std::exp(-r_aB.norm() / R); // # 2 ADDs - p->f_i += f_obst; + // p->f_i += f_obst; //commented since this version dont takes the field of view / angle to the border into account + + // I have read the paper again and on page 6 they say + // However, the formulas above for attractive and repulsive effects only hold for situations that are perceived in the desired direction e_alpha(t) of motion. + // I assumed that with formulas above its also meant for equation 8 (even though not explicitly mentioned their) + // # 14 flops: 9 MULTs, 4 ADDS, 1 SQRT + // + // $(12):\vec{F}_{\alpha B}(\vec{e}_{\alpha}, \vec{r}_{\alpha} - \vec{r}_{ B}) = w(\vec{e}_{\alpha}, -\vec{F}_{\alpha B})\vec{F}_{\alpha B}(\vec{r}_{\alpha} - \vec{r}_{ B})$ + // + p->f_i += f_obst * w(p->e, f_obst * -1); } }