modules/sparkler: s/rand/rand_r/ and wire up seed

This is a little contorted but not too bad.  The input to
particles_new() is just a const conf struct, so instead of
passing in the seed value for particles_t to contain, a pointer
to where the seed lives is passed in via the conf.  This requires
the caller to persist a seed somewhere outside the particles
instance, but at least in rototiller we already have that
conveniently in til_module_context_t.

8 files changed, 38 insertions, 35 deletions

diff --git a/src/modules/sparkler/particle.h b/src/modules/sparkler/particle.h
index 6a5bf73..a7c4138 100644
--- a/src/modules/sparkler/particle.h
+++ b/src/modules/sparkler/particle.h
@@ -43,7 +43,7 @@ struct particle_t {
 
 //#define rand_within_range(_min, _max) ((rand() % (_max - _min)) + _min)
 // the style of random number generator used by c libraries has less entropy in the lower bits meaning one shouldn't just use modulo, while this is slower, the results do seem a little different.
-#define rand_within_range(_min, _max) (int)(((float)_min) + ((float)rand() / (float)RAND_MAX) * (_max - _min))
+#define rand_within_range(_seedp, _min, _max) (int)(((float)_min) + ((float)rand_r(_seedp) / (float)RAND_MAX) * (_max - _min))
 
 #define INHERIT_OPS	NULL
 #define INHERIT_PROPS	NULL
diff --git a/src/modules/sparkler/particles.c b/src/modules/sparkler/particles.c
index 2389e93..f6adf13 100644
--- a/src/modules/sparkler/particles.c
+++ b/src/modules/sparkler/particles.c
@@ -49,6 +49,8 @@ particles_t * particles_new(const particles_conf_t *conf)
 {
 	particles_t	*particles;
 
+	assert(conf && conf->seedp);
+
 	particles = calloc(1, sizeof(particles_t));
 	if (!particles) {
 		return NULL;
@@ -66,8 +68,7 @@ particles_t * particles_new(const particles_conf_t *conf)
 
 	INIT_LIST_HEAD(&particles->active);
 
-	if (conf)
-		particles->conf = *conf;
+	particles->conf = *conf;
 
 	return particles;
 }
diff --git a/src/modules/sparkler/particles.h b/src/modules/sparkler/particles.h
index 1cb737f..a419e2c 100644
--- a/src/modules/sparkler/particles.h
+++ b/src/modules/sparkler/particles.h
@@ -12,6 +12,7 @@ typedef struct particles_conf_t {
 	unsigned	show_bsp_matches:1;
 	unsigned	show_bsp_matches_affected_only:1;
 	unsigned	show_bsp_leafs_min_depth;
+	unsigned	*seedp;
 } particles_conf_t;
 
 typedef struct particles_t particles_t;
diff --git a/src/modules/sparkler/rocket.c b/src/modules/sparkler/rocket.c
index 0949d30..8afceb4 100644
--- a/src/modules/sparkler/rocket.c
+++ b/src/modules/sparkler/rocket.c
@@ -38,12 +38,12 @@ static int rocket_init(particles_t *particles, const particles_conf_t *conf, par
 	}
 	rockets_cnt++;
 
-	ctxt->decay_rate = rand_within_range(ROCKET_MIN_DECAY_RATE, ROCKET_MAX_DECAY_RATE);
-	ctxt->longevity = rand_within_range(ROCKET_MIN_LIFETIME, ROCKET_MAX_LIFETIME);
+	ctxt->decay_rate = rand_within_range(conf->seedp, ROCKET_MIN_DECAY_RATE, ROCKET_MAX_DECAY_RATE);
+	ctxt->longevity = rand_within_range(conf->seedp, ROCKET_MIN_LIFETIME, ROCKET_MAX_LIFETIME);
 
-	ctxt->wander.x = (float)(rand_within_range(0, 628) - 314) / 10000.0f;
-	ctxt->wander.y = (float)(rand_within_range(0, 628) - 314) / 10000.0f;
-	ctxt->wander.z = (float)(rand_within_range(0, 628) - 314) / 10000.0f;
+	ctxt->wander.x = (float)(rand_within_range(conf->seedp, 0, 628) - 314) / 10000.0f;
+	ctxt->wander.y = (float)(rand_within_range(conf->seedp, 0, 628) - 314) / 10000.0f;
+	ctxt->wander.z = (float)(rand_within_range(conf->seedp, 0, 628) - 314) / 10000.0f;
 	ctxt->wander = v3f_normalize(&ctxt->wander);
 
 	ctxt->last_velocity = p->props->velocity;
@@ -75,18 +75,18 @@ static particle_status_t rocket_sim(particles_t *particles, const particles_conf
 
 		/* add a bunch of new explosion particles */
 		/* TODO: also particle-type-specific parameters, colors!  rocket bursts should be able to vary the color. */
-		n_xplode = rand_within_range(ROCKETS_XPLODE_MIN_SIZE, ROCKETS_XPLODE_MAX_SIZE);
+		n_xplode = rand_within_range(conf->seedp, ROCKETS_XPLODE_MIN_SIZE, ROCKETS_XPLODE_MAX_SIZE);
 		for (i = 0; i < n_xplode; i++) {
 			particle_props_t	props = *p->props;
 			particle_ops_t		*ops = &xplode_ops;
 
-			props.direction.x = ((float)(rand_within_range(0, 314159 * 2) - 314159) / 100000.0);
-			props.direction.y = ((float)(rand_within_range(0, 314159 * 2) - 314159) / 100000.0);
-			props.direction.z = ((float)(rand_within_range(0, 314159 * 2) - 314159) / 100000.0);
+			props.direction.x = ((float)(rand_within_range(conf->seedp, 0, 314159 * 2) - 314159) / 100000.0);
+			props.direction.y = ((float)(rand_within_range(conf->seedp, 0, 314159 * 2) - 314159) / 100000.0);
+			props.direction.z = ((float)(rand_within_range(conf->seedp, 0, 314159 * 2) - 314159) / 100000.0);
 			props.direction = v3f_normalize(&props.direction);
 
 			//props->velocity = ((float)rand_within_range(100, 200) / 100000.0);
-			props.velocity = ((float)rand_within_range(100, 300) / 100000.0);
+			props.velocity = ((float)rand_within_range(conf->seedp, 100, 300) / 100000.0);
 			particles_spawn_particle(particles, p, &props, ops);
 		}
 		return PARTICLE_DEAD;
@@ -100,18 +100,18 @@ static particle_status_t rocket_sim(particles_t *particles, const particles_conf
 	p->props->velocity += .00003;
 
 	/* spray some sparks behind the rocket */
-	n_sparks = rand_within_range(10, 40);
+	n_sparks = rand_within_range(conf->seedp, 10, 40);
 	for (i = 0; i < n_sparks; i++) {
 		particle_props_t	props = *p->props;
 
 		props.direction = v3f_negate(&props.direction);
 
-		props.direction.x += (float)(rand_within_range(0, 40) - 20) / 100.0;
-		props.direction.y += (float)(rand_within_range(0, 40) - 20) / 100.0;
-		props.direction.z += (float)(rand_within_range(0, 40) - 20) / 100.0;
+		props.direction.x += (float)(rand_within_range(conf->seedp, 0, 40) - 20) / 100.0;
+		props.direction.y += (float)(rand_within_range(conf->seedp, 0, 40) - 20) / 100.0;
+		props.direction.z += (float)(rand_within_range(conf->seedp, 0, 40) - 20) / 100.0;
 		props.direction = v3f_normalize(&props.direction);
 
-		props.velocity = (float)rand_within_range(10, 50) / 100000.0;
+		props.velocity = (float)rand_within_range(conf->seedp, 10, 50) / 100000.0;
 		particles_spawn_particle(particles, p, &props, &spark_ops);
 	}
 
diff --git a/src/modules/sparkler/simple.c b/src/modules/sparkler/simple.c
index 78e415b..3bc3076 100644
--- a/src/modules/sparkler/simple.c
+++ b/src/modules/sparkler/simple.c
@@ -28,8 +28,8 @@ static int simple_init(particles_t *particles, const particles_conf_t *conf, par
 {
 	simple_ctxt_t	*ctxt = p->ctxt;
 
-	ctxt->decay_rate = rand_within_range(SIMPLE_MIN_DECAY_RATE, SIMPLE_MAX_DECAY_RATE);
-	ctxt->lifetime = ctxt->longevity = rand_within_range(SIMPLE_MIN_LIFETIME, SIMPLE_MAX_LIFETIME);
+	ctxt->decay_rate = rand_within_range(conf->seedp, SIMPLE_MIN_DECAY_RATE, SIMPLE_MAX_DECAY_RATE);
+	ctxt->lifetime = ctxt->longevity = rand_within_range(conf->seedp, SIMPLE_MIN_LIFETIME, SIMPLE_MAX_LIFETIME);
 
 	if (!p->props->of_use) {
 		/* everything starts from the bottom center */
@@ -38,12 +38,12 @@ static int simple_init(particles_t *particles, const particles_conf_t *conf, par
 		p->props->position.z = 0;
 
 		/* TODO: direction random-ish within the range of a narrow upward facing cone */
-		p->props->direction.x = (float)(rand_within_range(0, 6) - 3) * .1f;
-		p->props->direction.y = 1.0f + (float)(rand_within_range(0, 6) - 3) * .1f;
-		p->props->direction.z = (float)(rand_within_range(0, 6) - 3) * .1f;
+		p->props->direction.x = (float)(rand_within_range(conf->seedp, 0, 6) - 3) * .1f;
+		p->props->direction.y = 1.0f + (float)(rand_within_range(conf->seedp, 0, 6) - 3) * .1f;
+		p->props->direction.z = (float)(rand_within_range(conf->seedp, 0, 6) - 3) * .1f;
 		p->props->direction = v3f_normalize(&p->props->direction);
 
-		p->props->velocity = (float)rand_within_range(300, 800) / 100000.0;
+		p->props->velocity = (float)rand_within_range(conf->seedp, 300, 800) / 100000.0;
 
 		p->props->drag = 0.03;
 		p->props->mass = 0.3;
@@ -70,7 +70,7 @@ static particle_status_t simple_sim(particles_t *particles, const particles_conf
 
 	/* create particles inheriting our type based on some silly conditions, with some tweaks to their direction */
 	if (ctxt->longevity == 42 || (ctxt->longevity > 500 && !(ctxt->longevity % 50))) {
-		int	i, num = rand_within_range(SIMPLE_MIN_SPAWN, SIMPLE_MAX_SPAWN);
+		int	i, num = rand_within_range(conf->seedp, SIMPLE_MIN_SPAWN, SIMPLE_MAX_SPAWN);
 
 		for (i = 0; i < num; i++) {
 			particle_props_t	props = *p->props;
@@ -78,14 +78,14 @@ static particle_status_t simple_sim(particles_t *particles, const particles_conf
 
 			if (i == (SIMPLE_MAX_SPAWN - 2)) {
 				ops = &rocket_ops;
-				props.velocity = (float)rand_within_range(60, 100) / 1000000.0;
+				props.velocity = (float)rand_within_range(conf->seedp, 60, 100) / 1000000.0;
 			} else {
-				props.velocity = (float)rand_within_range(30, 100) / 10000.0;
+				props.velocity = (float)rand_within_range(conf->seedp, 30, 100) / 10000.0;
 			}
 
-			props.direction.x += (float)(rand_within_range(0, 315 * 2) - 315) / 100.0;
-			props.direction.y += (float)(rand_within_range(0, 315 * 2) - 315) / 100.0;
-			props.direction.z += (float)(rand_within_range(0, 315 * 2) - 315) / 100.0;
+			props.direction.x += (float)(rand_within_range(conf->seedp, 0, 315 * 2) - 315) / 100.0;
+			props.direction.y += (float)(rand_within_range(conf->seedp, 0, 315 * 2) - 315) / 100.0;
+			props.direction.z += (float)(rand_within_range(conf->seedp, 0, 315 * 2) - 315) / 100.0;
 			props.direction = v3f_normalize(&props.direction);
 
 			particles_spawn_particle(particles, p, &props, ops); // XXX
diff --git a/src/modules/sparkler/spark.c b/src/modules/sparkler/spark.c
index 8627baa..3e45cc8 100644
--- a/src/modules/sparkler/spark.c
+++ b/src/modules/sparkler/spark.c
@@ -26,8 +26,8 @@ static int spark_init(particles_t *particles, const particles_conf_t *conf, part
 	p->props->drag = 20.0;
 	p->props->mass = 0.1;
 	p->props->virtual = 0;
-	ctxt->decay_rate = rand_within_range(SPARK_MIN_DECAY_RATE, SPARK_MAX_DECAY_RATE);
-	ctxt->lifetime = ctxt->longevity = rand_within_range(SPARK_MIN_LIFETIME, SPARK_MAX_LIFETIME);
+	ctxt->decay_rate = rand_within_range(conf->seedp, SPARK_MIN_DECAY_RATE, SPARK_MAX_DECAY_RATE);
+	ctxt->lifetime = ctxt->longevity = rand_within_range(conf->seedp, SPARK_MIN_LIFETIME, SPARK_MAX_LIFETIME);
 
 	return 1;
 }
diff --git a/src/modules/sparkler/sparkler.c b/src/modules/sparkler/sparkler.c
index c93c018..f0f2cb6 100644
--- a/src/modules/sparkler/sparkler.c
+++ b/src/modules/sparkler/sparkler.c
@@ -53,6 +53,7 @@ static til_module_context_t * sparkler_create_context(unsigned seed, unsigned ti
 						.show_bsp_matches = ((sparkler_setup_t *)setup)->show_bsp_matches,
 						.show_bsp_leafs_min_depth = ((sparkler_setup_t *)setup)->show_bsp_leafs_min_depth,
 						.show_bsp_matches_affected_only = ((sparkler_setup_t *)setup)->show_bsp_matches_affected_only,
+						.seedp = &ctxt->til_module_context.seed,
 					});
 	if (!ctxt->particles) {
 		free(ctxt);
diff --git a/src/modules/sparkler/xplode.c b/src/modules/sparkler/xplode.c
index 31f56fd..1534369 100644
--- a/src/modules/sparkler/xplode.c
+++ b/src/modules/sparkler/xplode.c
@@ -26,8 +26,8 @@ static int xplode_init(particles_t *particles, const particles_conf_t *conf, par
 {
 	xplode_ctxt_t	*ctxt = p->ctxt;
 
-	ctxt->decay_rate = rand_within_range(XPLODE_MIN_DECAY_RATE, XPLODE_MAX_DECAY_RATE);
-	ctxt->lifetime = ctxt->longevity = rand_within_range(XPLODE_MIN_LIFETIME, XPLODE_MAX_LIFETIME);
+	ctxt->decay_rate = rand_within_range(conf->seedp, XPLODE_MIN_DECAY_RATE, XPLODE_MAX_DECAY_RATE);
+	ctxt->lifetime = ctxt->longevity = rand_within_range(conf->seedp, XPLODE_MIN_LIFETIME, XPLODE_MAX_LIFETIME);
 
 	p->props->drag = 10.9;
 	p->props->mass = 0.3;
@@ -50,7 +50,7 @@ static particle_status_t xplode_sim(particles_t *particles, const particles_conf
 	if (!(ctxt->lifetime % 30)) {
 		particle_props_t	props = *p->props;
 
-		props.velocity = (float)rand_within_range(10, 50) / 10000.0;
+		props.velocity = (float)rand_within_range(conf->seedp, 10, 50) / 10000.0;
 		particles_spawn_particle(particles, p, &props, &xplode_ops);
 	}