1 files changed, 38 insertions, 5 deletions

diff --git a/experimental/tectonics/world.c b/experimental/tectonics/world.c
index cd56cdd..a1dd4de 100644
--- a/experimental/tectonics/world.c
+++ b/experimental/tectonics/world.c
@@ -8,6 +8,25 @@ struct centroid_t {
    int updates;
 };
 
+static void rebuild_tree(struct world_t *world)
+{
+   if (world->tree.nw != NULL) {
+      free_tree(world->tree.nw);
+      free_tree(world->tree.ne);
+      free_tree(world->tree.sw);
+      free_tree(world->tree.se);
+      world->tree.nw = NULL;
+      world->tree.ne = NULL;
+      world->tree.sw = NULL;
+      world->tree.se = NULL;
+   }
+   world->tree.id = -1;
+
+   for (int i=0; i<world->n_points; i++) {
+      insert(&(world->tree), world->points, i);
+   }
+}
+
 static void relax_points(struct world_t *world, int iterations)
 {
    struct centroid_t *centroid =
@@ -26,12 +45,19 @@ static void relax_points(struct world_t *world, int iterations)
       double x = rand01();
       double y = rand01();
       int closest = get_closest(&(world->tree),
+				world->points,
 				(struct point_t){x, y});
 
-      int t = centroid[closest].updates;
-      centroid[closest].x = (t*centroid[closest].x + x)/(t+1);
-      centroid[closest].y = (t*centroid[closest].y + y)/(t+1);
-      centroid[closest].updates += 1;
+      if (closest == -1) {
+	 printf("WARN: bad closest point!\n");
+      }
+      else {
+	 struct centroid_t *c = centroid + closest;
+	 int u = c->updates;
+	 c->x = (u*c->x + x)/(u+1);
+	 c->y = (u*c->y + y)/(u+1);
+	 c->updates += 1;
+      }
    }
 
    for (int i=0; i<world->n_points; i++) {
@@ -41,6 +67,8 @@ static void relax_points(struct world_t *world, int iterations)
       pt->y = c->y;
    }
 
+   rebuild_tree(world);
+
    free(centroid);
 }
 
@@ -63,8 +91,13 @@ void create_world(struct world_t *world, int n_points)
       pt->x = rand01();
       pt->y = rand01();
 
-      insert(&(world->tree), world->points, i);
+      //insert(&(world->tree), world->points, i);
    }
+
+   rebuild_tree(world);
+
+   for (int i=0; i<10; i++)
+      relax_points(world, 100000);
 }