3 files changed, 24 insertions, 16 deletions

diff --git a/experimental/tectonics/quadtree.c b/experimental/tectonics/quadtree.c
index dead9f2..0f3f9c7 100644
--- a/experimental/tectonics/quadtree.c
+++ b/experimental/tectonics/quadtree.c
@@ -133,3 +133,16 @@ void draw_quadtree(cairo_t *cr, struct quadtree_node_t *node)
       draw_quadtree(cr, node->se);
    }
 }
+
+
+void free_tree(struct quadtree_node_t *node)
+{
+   if (node->nw != NULL) {
+      free_tree(node->nw);
+      free_tree(node->ne);
+      free_tree(node->sw);
+      free_tree(node->se);
+   }
+
+   free(node);
+}
diff --git a/experimental/tectonics/tectonics.h b/experimental/tectonics/tectonics.h
index 5f39ff7..85b86fe 100644
--- a/experimental/tectonics/tectonics.h
+++ b/experimental/tectonics/tectonics.h
@@ -48,6 +48,7 @@ bool insert(struct quadtree_node_t *node,
 int get_closest(struct quadtree_node_t *root,
 		struct point_t pt);
 void draw_quadtree(cairo_t *cr, struct quadtree_node_t *root);
+void free_tree(struct quadtree_node_t *root);
 
 /* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  *
diff --git a/experimental/tectonics/world.c b/experimental/tectonics/world.c
index cfc5d14..cd56cdd 100644
--- a/experimental/tectonics/world.c
+++ b/experimental/tectonics/world.c
@@ -8,21 +8,6 @@ struct centroid_t {
    int updates;
 };
 
-static int closest_point(struct world_t *world, double x, double y)
-{
-   double dist = 1e9;
-   int closest = -1;
-   for (int i=0; i<world->n_points; i++) {
-      struct point_t *pt = world->points + i;
-      double d = distance(x, y, pt->x, pt->y);
-      if (d <= dist) {
-	 dist = d;
-	 closest = i;
-      }
-   }
-   return closest;
-}
-
 static void relax_points(struct world_t *world, int iterations)
 {
    struct centroid_t *centroid =
@@ -40,7 +25,8 @@ static void relax_points(struct world_t *world, int iterations)
       printf("%02f%%\n", 100*((double)i+1)/iterations);
       double x = rand01();
       double y = rand01();
-      int closest = closest_point(world, x, y);
+      int closest = get_closest(&(world->tree),
+				(struct point_t){x, y});
 
       int t = centroid[closest].updates;
       centroid[closest].x = (t*centroid[closest].x + x)/(t+1);
@@ -54,6 +40,8 @@ static void relax_points(struct world_t *world, int iterations)
       pt->x = c->x;
       pt->y = c->y;
    }
+
+   free(centroid);
 }
 
 void create_world(struct world_t *world, int n_points)
@@ -82,6 +70,12 @@ void create_world(struct world_t *world, int n_points)
 
 void free_world(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);
+   }
    free(world->points);
 }