diff --git a/charge/charge.c b/charge/charge.c
index 42e91b6290dcac17b238589c63f75aa87a3087d7..2158dfdc2b20123b2103dcc7b6e462ba151edaf3 100644
--- a/charge/charge.c
+++ b/charge/charge.c
@@ -72,5 +72,46 @@ charge_t charge_create(double q, vec2 pos) {
}
double random_charge_q(bool positive) {
- return rand_one() * (positive ? 1 : -1);
+ return (rand() % 100) * (positive ? 1 : -1);
+}
+
+vec2 electristatic_force(charge_t a, charge_t b) {
+ vec2 rab = vec2_sub(b.pos, a.pos);
+ vec2 res = vec2_mul(
+ rab, K * (((a.q * 10e-6) * (b.q * 10e-6)) / pow(vec2_norm(rab), 2)));
+
+ printf("COEF: %.25f\n", (a.q * 10e-6) * (b.q * 10e-6));
+ return res;
+}
+
+vec2 resulting_electrostatic_force(charge_t *charges, int num_charges,
+ charge_t a) {
+ vec2 resulting = vec2_create_zero();
+
+ for (int i = 0; i < num_charges; i++) {
+ // Very unlickly to have two charges with the exact same charge
+ if (charges[i].q == a.q)
+ continue;
+
+ vec2 ef = electristatic_force(a, charges[i]);
+ resulting = vec2_add(resulting, ef);
+ }
+
+ return resulting;
+}
+
+void update_charge_pos(charge_t *charges, int num_charges, charge_t *a) {
+ vec2 resulting = resulting_electrostatic_force(charges, num_charges, *a);
+ a->pos = vec2_add(a->pos, resulting);
+}
+
+void update_simulation(charge_t *charges, int num_charges) {
+ for (int i = 0; i < num_charges; i++) {
+ vec2 resulting =
+ resulting_electrostatic_force(charges, num_charges, charges[i]);
+ printf("RES: %.19f\n", vec2_norm(resulting));
+ charges[i].pos = vec2_add(charges[i].pos, resulting);
+ }
+
+ printf("%.19f, %.19f\n", charges[0].pos.x, charges[0].pos.x);
}
\ No newline at end of file
diff --git a/charge/charge.h b/charge/charge.h
index 097fe21859857c0fa949941563d4d0b62aa85d35..57fc6687f5111c5b5e6d10e1001fcdf9a975666a 100644
--- a/charge/charge.h
+++ b/charge/charge.h
@@ -20,6 +20,7 @@
#include <stdlib.h>
#define K 8.988e9
+#define ELEMENTARY_CHARGE 1.602176634e-19
#define CHARGE_RADIUS 10
#define EPS 0.015
#define UNIV_MIN_X 0
@@ -118,4 +119,42 @@ charge_t charge_create(double q, vec2 pos);
*/
double random_charge_q(bool positive);
+/**
+ * @brief Compute the electrostatic force between two charges
+ *
+ * @param a
+ * @param b
+ * @return vec2
+ */
+vec2 electristatic_force(charge_t a, charge_t b);
+
+/**
+ * @brief Compute the resulting electrostatic force
+ *
+ * @param charges
+ * @param num_charges
+ * @param a
+ * @return vec2
+ */
+vec2 resulting_electrostatic_force(charge_t *charges, int num_charges,
+ charge_t a);
+
+/**
+ * @brief Update the pos of the given charge based on the resulting
+ * electrostatic force
+ *
+ * @param charges
+ * @param num_charges
+ * @param a
+ */
+void update_charge_pos(charge_t *charges, int num_charges, charge_t *a);
+
+/**
+ * @brief Update the whole simulation
+ *
+ * @param charges
+ * @param num_charges
+ */
+void update_simulation(charge_t *charges, int num_charges);
+
#endif
\ No newline at end of file
diff --git a/draw/draw.c b/draw/draw.c
index e178166fbee66f348d743a45036523ef11c9e2a3..021825507bdf84498ec63dcfde193fdc065f6ab8 100644
--- a/draw/draw.c
+++ b/draw/draw.c
@@ -202,7 +202,7 @@ void draw_charges(charge_t *charges, int num_charges, int w, int h) {
draw_circle(chCoord, CHARGE_RADIUS);
char charge_str[8];
- snprintf(charge_str, 8, "%.4f", charges[i].q);
+ snprintf(charge_str, 8, "%.0f", charges[i].q);
vec2 text_pos = vec2_create(chCoord.x, chCoord.y + CHARGE_RADIUS + 4);
draw_textbox(text_pos, charge_str);
}
diff --git a/main.c b/main.c
index ae82fc98583f96190a75a6afb2faae1c5aef18fa..f653e82de46a0ae8f6edd717609faea0f919f9ab 100644
--- a/main.c
+++ b/main.c
@@ -29,6 +29,9 @@
#define UNUSED(x) x
#endif
+#define ONE_SECOND_IN_MILLISECONDS 1000
+#define REFRESH_RATE 200
+
#define WINDOW_WIDTH 800
#define WINDOW_HEIGHT 800
#define NB_CHARGES 5
@@ -42,11 +45,24 @@ int charge_count = NB_CHARGES;
vec2 starting_points[NB_POINTS];
vec2 default_charges_pos[MAXIMUM_CHARGES];
double default_charges[MAXIMUM_CHARGES];
+charge_t *charges;
-bool toggle_lines_view = true;
+bool toggle_lines_view = false;
bool toggle_vector_view = false;
bool toggle_heatmap_view = false;
+void update() { update_simulation(charges, charge_count); };
+
+void update_timer() {
+ update();
+ glutTimerFunc(ONE_SECOND_IN_MILLISECONDS / REFRESH_RATE, update_timer, 0);
+}
+
+void draw_timer() {
+ glutPostRedisplay();
+ glutTimerFunc(ONE_SECOND_IN_MILLISECONDS / REFRESH_RATE, draw_timer, 0);
+}
+
/**
* @brief Generate a grid of points
*
@@ -72,11 +88,6 @@ void display() {
glClearColor(0, 0, 0, 1);
glClear(GL_COLOR_BUFFER_BIT);
- // Generate all the charges
- charge_t charges[charge_count];
- for (int i = 0; i < charge_count; i++)
- charges[i] = charge_create(default_charges[i], default_charges_pos[i]);
-
if (toggle_heatmap_view)
draw_heatmap(charges, charge_count, WINDOW_WIDTH, WINDOW_HEIGHT);
@@ -110,6 +121,7 @@ void handle_mouse_input(int button, int state, int x, int y) {
if (state == GLUT_UP)
return;
+ // Define new charges attributes
if (button == GLUT_LEFT_BUTTON || button == GLUT_RIGHT_BUTTON) {
charge_count += 1;
default_charges_pos[charge_count - 1] =
@@ -122,6 +134,13 @@ void handle_mouse_input(int button, int state, int x, int y) {
if (button == GLUT_RIGHT_BUTTON)
default_charges[charge_count - 1] = random_charge_q(false);
+ // Realloc charge array when a new one is added
+ charges = realloc(charges, sizeof(charge_t) * charge_count);
+
+ // Redefine all charges infos
+ for (int i = 0; i < charge_count; i++)
+ charges[i] = charge_create(default_charges[i], default_charges_pos[i]);
+
glutPostRedisplay();
}
@@ -158,12 +177,18 @@ void keyboard(unsigned char key, int UNUSED(x), int UNUSED(y)) {
int main(int argc, char **argv) {
srand(time(NULL));
+ charges = malloc(sizeof(charge_t) * charge_count);
+
// Generate all default charges
for (int i = 0; i < charge_count; i++) {
default_charges[i] = random_charge_q((bool)(rand() % 2 == 0));
default_charges_pos[i] = vec2_create(rand_one(), rand_one());
}
+ // Init charges
+ for (int i = 0; i < charge_count; i++)
+ charges[i] = charge_create(default_charges[i], default_charges_pos[i]);
+
// Generate all field lines starting points
generate_points(starting_points);
@@ -184,9 +209,14 @@ int main(int argc, char **argv) {
glutMouseFunc(handle_mouse_input);
glutKeyboardFunc(keyboard);
+ // glutTimerFunc(ONE_SECOND_IN_MILLISECONDS / REFRESH_RATE, update_timer,
+ // 0); glutTimerFunc(ONE_SECOND_IN_MILLISECONDS / REFRESH_RATE, draw_timer,
+ // 0);
+
glutMainLoop();
// Object destroy
glutDestroyWindow(window);
+ free(charges);
return EXIT_SUCCESS;
}
\ No newline at end of file