Rewrite merge and update to handle edge cases and full capacity

leonmavr · Sep 21, 2024 · 7ce93b7 · 7ce93b7
1 parent 48b9260
commit 7ce93b7
Show file tree

Hide file tree

Showing 2 changed files with 16 additions and 17 deletions.
diff --git a/src/quad.c b/src/quad.c
@@ -230,12 +230,7 @@ static void node_remove_point(node_t* node, point_t* point) {
     if (node_is_leaf(node)) {
         for (int i = 0; i < node->count; ++i) {
             if (node->points[i].id == point->id && node->count > 1) {
-#if 1
-                // shift last point into deleted point
-                memcpy(&node->points[i], &node->points[--node->count], sizeof(node->points[0]));
-#else
-                memcpy(&node->points[i], &node->points[node->count], sizeof(node->points[0]));
-#endif
+                memcpy(&node->points[i], &node->points[--node->count], sizeof(point_t));
                 return;
             } else if (node->points[i].id == point->id && node->count == 1) {
                 node->count--;
@@ -294,12 +289,16 @@ static void node_merge(node_t* node) {
                     (node->count)++;
                 }
             }
-            for (int i = 0; i < 4; ++i) {
-                if (children[i] != NULL) {
-                    free(children[i]->points);
-                    free(children[i]);
-                }
-            }
+            free(node->nw);
+            free(node->nw->points);
+            free(node->ne);
+            free(node->ne->points);
+            free(node->se);
+            free(node->se->points);
+            free(node->sw);
+            free(node->sw->points);
+            // make the current node a leaf
+            node->nw = node->ne = node->se = node->sw = NULL;
         }
     }
 }
@@ -315,10 +314,8 @@ void node_del_all(node_t* node) {
     node_del_all(node->ne);
     node_del_all(node->sw);
     node_del_all(node->se);
-    if (node != NULL) {
-        free(node->points);
-        free(node);
-    }
+    free(node->points);
+    free(node);
 }
 
 void qtree_del(quadtree_t* qtree) {

diff --git a/test/test.c b/test/test.c
@@ -52,6 +52,7 @@ int main(int argc, char** argv) {
     // Update point 
     //-------------------------------------------------------------------------
     point_t pnew = {90, 90};
+    // {108, 120} -> 90, 90
     qtree_update_point(&qtree, &points[6], &pnew);
     NTEST_ASSERT(qtree.root->nw->sw->points[0].id == pnew.id);
     NTEST_ASSERT(qtree.root->sw->ne->count == 1 && qtree.root->nw->sw->count == 1);
@@ -61,6 +62,7 @@ int main(int argc, char** argv) {
     // now sw->nw should have one point and so should sw->ne; mergeable into sw
     qtree_merge(&qtree);
     // p7, p8 should have propagated up into sw
+    printf("%d\n", qtree.root->sw->count);
     NTEST_ASSERT(qtree.root->sw->count == 2);
     NTEST_ASSERT((are_points_equal(&qtree.root->sw->points[1], &points[7]) &&
         are_points_equal(&qtree.root->sw->points[0], &points[8])) ||
@@ -72,6 +74,6 @@ int main(int argc, char** argv) {
     NTEST_ASSERT(qtree.root->nw->se->sw->count == 1);
     qtree_remove_point(&qtree, &points[5]);
     NTEST_ASSERT(qtree.root->nw->se->sw->count == 0);
-    //qtree_del(&qtree);
+    qtree_del(&qtree);
     return 0;
 }