libs/din: pass seed to din_new()

also update call sites in modules/{meta2d,swab} accordingly

4 files changed, 15 insertions, 13 deletions

diff --git a/src/libs/din/din.c b/src/libs/din/din.c
index c0bac93..4290d41 100644
--- a/src/libs/din/din.c
+++ b/src/libs/din/din.c
@@ -8,16 +8,17 @@
 #include "v3f.h"
 
 typedef struct din_t {
-	int	width, height, depth;
-	int	W_x_H;
-	v3f_t	grid[];
+	int		width, height, depth;
+	unsigned	seed;
+	int		W_x_H;
+	v3f_t		grid[];
 } din_t;
 
 
 /* return random number between -1 and +1 */
-static inline float randf(void)
+static inline float randf(unsigned *seed)
 {
-	return 2.f / RAND_MAX * rand() - 1.f;
+	return 2.f / RAND_MAX * rand_r(seed) - 1.f;
 }
 
 
@@ -30,9 +31,9 @@ void din_randomize(din_t *din)
 			for (x = 0; x < din->width; x++) {
 				v3f_t	r;
 
-				r.x = randf();
-				r.y = randf();
-				r.z = randf();
+				r.x = randf(&din->seed);
+				r.y = randf(&din->seed);
+				r.z = randf(&din->seed);
 
 				din->grid[z * din->W_x_H + y * din->width + x] = v3f_normalize(&r);
 			}
@@ -41,7 +42,7 @@ void din_randomize(din_t *din)
 }
 
 
-din_t * din_new(int width, int height, int depth)
+din_t * din_new(int width, int height, int depth, unsigned seed)
 {
 	din_t	*din;
 
@@ -56,6 +57,7 @@ din_t * din_new(int width, int height, int depth)
 	din->width = width;
 	din->height = height;
 	din->depth = depth;
+	din->seed = seed;
 
 	/* premultiply this since we do it a lot in addressing din->grid[] */
 	din->W_x_H = width * height;
diff --git a/src/libs/din/din.h b/src/libs/din/din.h
index baa3ebb..97823b6 100644
--- a/src/libs/din/din.h
+++ b/src/libs/din/din.h
@@ -4,7 +4,7 @@
 typedef struct din_t din_t;
 typedef struct v3f_t v3f_t;
 
-din_t * din_new(int width, int height, int depth);
+din_t * din_new(int width, int height, int depth, unsigned seed);
 void din_free(din_t *din);
 void din_randomize(din_t *din);
 float din(din_t *din, v3f_t *coordinate);
diff --git a/src/modules/meta2d/meta2d.c b/src/modules/meta2d/meta2d.c
index 1ab444c..1bb8827 100644
--- a/src/modules/meta2d/meta2d.c
+++ b/src/modules/meta2d/meta2d.c
@@ -76,8 +76,8 @@ static til_module_context_t * meta2d_create_context(unsigned seed, unsigned tick
 		return NULL;
 
 	/* perlin noise is used for some organic-ish random movement of the balls */
-	ctxt->din_a = din_new(10, 10, META2D_NUM_BALLS + 2);
-	ctxt->din_b = din_new(10, 10, META2D_NUM_BALLS + 2);
+	ctxt->din_a = din_new(10, 10, META2D_NUM_BALLS + 2, seed);
+	ctxt->din_b = din_new(10, 10, META2D_NUM_BALLS + 2, seed);
 
 	for (int i = 0; i < META2D_NUM_BALLS; i++) {
 		meta2d_ball_t	*ball = &ctxt->balls[i];
diff --git a/src/modules/swab/swab.c b/src/modules/swab/swab.c
index 5424bf6..9047f68 100644
--- a/src/modules/swab/swab.c
+++ b/src/modules/swab/swab.c
@@ -74,7 +74,7 @@ static til_module_context_t * swab_create_context(unsigned seed, unsigned ticks,
 	if (!ctxt)
 		return NULL;
 
-	ctxt->din = din_new(12, 12, 100);
+	ctxt->din = din_new(12, 12, 100, seed);
 	if (!ctxt->din) {
 		free(ctxt);
 		return NULL;