Merge remote-tracking branch 'origin/physics' into physics

# Conflicts:
#	src/draw.c

src/draw.c

@@ -39,14 +39,14 @@ void gfx_draw_circle(struct gfx_context_t *ctxt, coordinates c, uint32_t r, uint
     int y = r;
     int d = r - 1;
     while(y >= x){ 
-		gfx_putpixel(ctxt, c.row + x, c.column + y, color);
-		gfx_putpixel(ctxt, c.row + y, c.column + x, color);
-		gfx_putpixel(ctxt, c.row - x, c.column + y, color);
-		gfx_putpixel(ctxt, c.row - y, c.column + x, color);
-		gfx_putpixel(ctxt, c.row + x, c.column - y, color);
-		gfx_putpixel(ctxt, c.row + y, c.column - x, color);
-		gfx_putpixel(ctxt, c.row - x, c.column - y, color);
-		gfx_putpixel(ctxt, c.row - y, c.column - x, color);
+        gfx_putpixel(ctxt, c.column + x, c.row + y, color);
+        gfx_putpixel(ctxt, c.column + y, c.row + x, color);
+        gfx_putpixel(ctxt, c.column - x, c.row + y, color);
+        gfx_putpixel(ctxt, c.column - y, c.row + x, color);
+        gfx_putpixel(ctxt, c.column + x, c.row - y, color);
+        gfx_putpixel(ctxt, c.column + y, c.row - x, color);
+        gfx_putpixel(ctxt, c.column - x, c.row - y, color);
+        gfx_putpixel(ctxt, c.column - y, c.row - x, color);
         if(d >= 2*x){ 
             d = d-2*x-1;
             x++;

src/field.c

@@ -3,12 +3,12 @@
 
 #include "draw.h"
 #include "field.h"
-
+#include "draw.h"
+#include "../utils/utils.h"
 
 #define SIGN_SIZE 10
 #define CHARGE_R 25
 
-
 // Compute E*qP/norm(qP)
 // Return false if norm(qP) < eps
 /// qP = vectoriel(P-q)
@@ -34,41 +34,98 @@ 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;
+}
+
+bool is_in_screen(coordinates_t pos){
+	if(pos.column > WID || pos.column < 0)
+		return false;
+
+	if(pos.row > HEI || pos.row < 0)
+		return false;
+	
+	return true;
+}
+
+bool draw_field_line_point(struct gfx_context_t *ctxt, charge_t *charges, int num_charges, double x0, double x1, double y0, double y1, vec2 pos, vec2 *pos_next, double delta){
+	vec2 e;
+	compute_total_normalized_e(charges, num_charges, pos, 0.01, &e);
+	double norm_e = vec2_norm(e);
+
+	pos_next->x = pos.x + delta * (e.x / norm_e);
+	pos_next->y = pos.y + delta * (e.y / norm_e);
+	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);
+
+	gfx_draw_line(ctxt, coordinate_pos, coordinate_pos_next, COLOR_YELLOW);
+
+	return !is_in_screen(coordinate_pos);
+}
+
+bool line_reach_charge(vec2 pos, charge_t * charges, double num_charges, double dx){
+	for (int j = 0; j < num_charges; j++){
+		if(vec2_norm(vec2_sub(pos, charges[j].pos)) < dx / HEI){
+			return true;
+		}
+	}
+	return false;
+}
+
 
 // Compute and then draw all the points belonging to a field line,
 // starting from pos0.
 // Returns false if pos0 is not a valid position
 // (for example if pos0 is too close to a charge).
-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) {
-	return EXIT_SUCCESS;
+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_positive = vec2_create(pos0.x, pos0.y);
+	vec2 pos_negative = vec2_create(pos0.x, pos0.y);
+	vec2 pos_next_positive;
+	vec2 pos_next_negative;
+	bool stop = false;
+	// * 5 à supprimer lorsque le code est optimisé
+	double delta = compute_delta_x() * 5;
+	int max_for = 50; 
+	for (int i = 0; i < max_for && !stop; i++)
+	{
+		stop = line_reach_charge(pos_positive, charges, num_charges, dx) || line_reach_charge(pos_negative, charges, num_charges, dx);
+		if(!stop){
+			stop = draw_field_line_point(ctxt, charges, num_charges, x0, x1, y0, y1, pos_positive, &pos_next_positive, delta) ||
+					draw_field_line_point(ctxt, charges, num_charges, x0, x1, y0, y1, pos_negative, &pos_next_negative, -delta);
+			pos_positive = pos_next_positive;
+			pos_negative = pos_next_negative;
+		}
+	}
+
+	return !stop;
 }
 
 // Draw all the charges
 // A circle with minus sign for negative charges
 // A circle with a plus sign for positive charges
-static void
-draw_charges(struct gfx_context_t *context, charge_t *charges, int num_charges, double x0, double x1, double y0,
-			 double y1) {
-	for (int i = 0; i < num_charges; i++) {
-		coordinates_t charge_center = position_to_coordinates(CHARGE_R, CHARGE_R, x0, x1, y0, y1, charges[i].pos);
+static void draw_charges(struct gfx_context_t *context, charge_t *charges, int num_charges, double x0, double x1, double y0, double y1) {
+	for (int i = 0; i < num_charges; i++)
+	{
+		coordinates_t charge_center = position_to_coordinates(WID, HEI, x0, x1, y0, y1, charges[i].pos);
 		gfx_draw_circle(context, charge_center, CHARGE_R, COLOR_WHITE);
 
-		coordinates_t sign_dst;
+		coordinates_t sign_src = charge_center;
+		coordinates_t sign_dst = charge_center;
 		uint32_t sign_color = COLOR_RED;
 		if (charges[i].q > 0) {
 			sign_color = COLOR_BLUE;
-			sign_dst.row = charge_center.row + SIGN_SIZE;
-			gfx_draw_line(context, charge_center, sign_dst, sign_color);
-			sign_dst.row = charge_center.row - SIGN_SIZE;
-			gfx_draw_line(context, charge_center, sign_dst, sign_color);
+			sign_src.row -= SIGN_SIZE;
+			sign_dst.row += SIGN_SIZE;
+			gfx_draw_line(context, sign_src, sign_dst, sign_color);
+			sign_src.row = charge_center.row;
+			sign_dst.row = charge_center.row;
 		}
 
-		sign_dst.column = charge_center.column + SIGN_SIZE;
-		gfx_draw_line(context, charge_center, sign_dst, sign_color);
-		sign_dst.column = charge_center.column - SIGN_SIZE;
-		gfx_draw_line(context, charge_center, sign_dst, sign_color);
+		sign_src.column -= SIGN_SIZE;
+		sign_dst.column += SIGN_SIZE;
+		gfx_draw_line(context, sign_src, sign_dst, sign_color);
 	}
 }
 
@@ -80,9 +137,10 @@ 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(rand_one(), rand_one());
 		draw_field_line(ctxt, charges, num_charges, dx, pos0, x0, x1, y0, y1);
 	}
 }

src/field.h

@@ -6,6 +6,10 @@
 #include "../utils/utils.h"
 #include <stdio.h>
 
+#define SIDE_LEN 1000
+#define WID SIDE_LEN
+#define HEI WID
+
 // Compute E*qP/norm(qP)
 // Return false if norm(qP) < eps
 bool compute_e(charge_t c, vec2 p, double eps, vec2 *e);
@@ -18,16 +22,12 @@ bool compute_total_normalized_e(charge_t *charges, int num_charges, vec2 p, doub
 // starting from pos0.
 // Returns false if pos0 is not a valid position
 // (for example if pos0 is too close to a charge).
-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);
+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);
 
 // Draw all the charges
 // A circle with minus sign for negative charges
 // A circle with a plus sign for positive charges
-static void
-draw_charges(struct gfx_context_t *context, charge_t *charges, int num_charges, double x0, double x1, double y0,
-			 double y1);
+static void draw_charges(struct gfx_context_t *context, charge_t *charges, int num_charges, double x0, double x1, double y0, double y1);
 
 void draw_everything(
 		struct gfx_context_t *ctxt,

src/main.c

@@ -4,24 +4,22 @@
 #include "draw.h"
 #include "field.h"
 #include "../utils/utils.h"
+#include "field.h"
 
-
-#define SIDE_LEN 1000
-#define WID SIDE_LEN
-#define HEI WID
 #define NCHARGES 2
-#define DX 0.0005
-#define NLINES 32
+#define DX 25
+#define NLINES 5
 
 
 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)},
+		charge_create(-0.25, vec2_create(0.25, 0.5)),
+		charge_create(0.25, vec2_create(0.75, 0.5))
 	};
 	struct gfx_context_t *ctxt = gfx_create("elec", WID, HEI);
+
 	draw_everything(ctxt, charges, NCHARGES, NLINES, DX, 0.0, 1.0, 0.0, 1.0);
+
 	while (gfx_keypressed() != SDLK_ESCAPE) gfx_present(ctxt);
 	gfx_destroy(ctxt);
 	return EXIT_SUCCESS;