Modification génération ligne

src/field.c

@@ -9,7 +9,6 @@
 #define SIGN_SIZE 10
 #define CHARGE_R 25
 
-
 // Compute E*qP/norm(qP)
 // Return false if norm(qP) < eps
 /// qP = vectoriel(P-q)
@@ -35,6 +34,11 @@ bool compute_total_normalized_e(charge_t *charges, int num_charges, vec2 p, doub
 	return true;
 }
 
+double compute_delta_x(){
+	double result = pow(WID, 2) + pow(HEI, 2);
+	result = sqrt(result);
+	return 1 / result;
+}
 
 // Compute and then draw all the points belonging to a field line,
 // starting from pos0.
@@ -43,12 +47,27 @@ bool compute_total_normalized_e(charge_t *charges, int num_charges, vec2 p, doub
 static bool draw_field_line(struct gfx_context_t *ctxt, charge_t *charges, int num_charges, double dx, vec2 pos0, double x0, double x1, double y0, double y1) {
 	vec2 pos = vec2_create(pos0.x, pos0.y);
 	vec2 pos_sum;
-	for (int i = 0; i < num_charges; i++)
+	vec2 pos_next;
+	vec2 e;
+	double delta = compute_delta_x();
+	// Remplacer par une boucle qui s'arrête lorsqu'on atteint une charge
+	for (int i = 0; i < 100; i++)
 	{
-		//compute_e(charges[i], ..., &pos_sum);
+		compute_total_normalized_e(charges, num_charges, pos, 0.01, &e);
+		pos_next.x = pos.x + delta * (e.x / vec2_normalize(e).x);
+		pos_next.y = pos.y + delta * (e.y / vec2_normalize(e).y);
+
+		//printf("%f + %f * (%f / %f)\n", pos.x, delta, e.x, vec2_normalize(e).x);
+		//printf("%f %f\n", pos_next.x, pos_next.y);
+
+		coordinates_t coordinate_pos = position_to_coordinates(WID, HEI, x0, x1, y0, y1, pos);
+		coordinates_t coordinate_pos_next = position_to_coordinates(WID, HEI, x0, x1, y0, y1, pos_next);
+		//printf("%d %d\n", charge_1.column, charge_1.row);
+		//printf("%d %d\n\n", charge_2.column, charge_2.row);
+		gfx_draw_line(ctxt, coordinate_pos, coordinate_pos_next, COLOR_YELLOW);
+		pos = pos_next;
 	}
 	
-	//vec2 pos_next = 
 	return EXIT_SUCCESS;
 }
 
@@ -87,9 +106,10 @@ void draw_everything(
 		double dx,
 		double x0, double x1,
 		double y0, double y1) {
+	srand(time(NULL));
 	draw_charges(ctxt, charges, num_charges, x0, x1, y0, y1);
 	for (int i = 0; i < num_lines; ++i) {
-		vec2 pos0 = vec2_normalize(vec2_create(rand(), rand()));
+		vec2 pos0 = vec2_create((double)rand() / RAND_MAX, (double)rand() / RAND_MAX);
 		draw_field_line(ctxt, charges, num_charges, dx, pos0, x0, x1, y0, y1);
 	}
 }

src/main.c

@@ -12,7 +12,6 @@
 
 
 int main() {
-	srand(time(NULL));
 	charge_t charges[NCHARGES] = {
 			{.q=-0.25, .pos=vec2_create(0.25, 0.5)},
 			{.q=0.25, .pos=vec2_create(0.75, 0.5)},