From 1b1f00e70564d6acb2b1e09b0a5f430da4e4b8a3 Mon Sep 17 00:00:00 2001
From: Tavian Barnes <tavianator@gmail.com>
Date: Thu, 15 Apr 2010 15:15:39 -0400
Subject: Support infinitely large bounding boxes.

---
 libdimension/bvst.c     | 18 ++++++++----------
 libdimension/geometry.c |  9 +++++++++
 2 files changed, 17 insertions(+), 10 deletions(-)

diff --git a/libdimension/bvst.c b/libdimension/bvst.c
index c0888bb..7a57c76 100644
--- a/libdimension/bvst.c
+++ b/libdimension/bvst.c
@@ -105,12 +105,10 @@ dmnsn_bvst_insert(dmnsn_bvst *tree, dmnsn_object *object)
 
   dmnsn_bvst_node *node = dmnsn_new_bvst_node(), *parent = tree->root;
 
-  node->contains = NULL;
-  node->container = NULL;
-  node->parent = NULL;
-  node->object = object;
-
-  /* Calculate the new bounding box */
+  node->contains     = NULL;
+  node->container    = NULL;
+  node->parent       = NULL;
+  node->object       = object;
   node->bounding_box = object->bounding_box;
 
   /* Now insert the node */
@@ -122,9 +120,9 @@ dmnsn_bvst_insert(dmnsn_bvst *tree, dmnsn_object *object)
                                        node->bounding_box.max))
     {
       /* parent fully contains node */
-      if (parent->contains)
+      if (parent->contains) {
         parent = parent->contains;
-      else {
+      } else {
         /* We found our parent; insert node into the tree */
         parent->contains = node;
         node->parent = parent;
@@ -135,9 +133,9 @@ dmnsn_bvst_insert(dmnsn_bvst *tree, dmnsn_object *object)
          already */
       dmnsn_bvst_node_swallow(node, parent->bounding_box);
       /* node now fully contains parent */
-      if (parent->container)
+      if (parent->container) {
         parent = parent->container;
-      else {
+      } else {
         /* We found our parent; insert node into the tree */
         parent->container = node;
         node->parent = parent;
diff --git a/libdimension/geometry.c b/libdimension/geometry.c
index 7dc6725..304f21d 100644
--- a/libdimension/geometry.c
+++ b/libdimension/geometry.c
@@ -363,6 +363,15 @@ dmnsn_matrix_vector_mul(dmnsn_matrix lhs, dmnsn_vector rhs)
 dmnsn_bounding_box
 dmnsn_matrix_bounding_box_mul(dmnsn_matrix trans, dmnsn_bounding_box box)
 {
+  /* Infinite bounding box support */
+  if (isinf(box.min.x) || isinf(box.min.y) || isinf(box.min.z)
+      || isinf(box.max.x) || isinf(box.max.y) || isinf(box.max.z))
+  {
+    box.min = dmnsn_new_vector(-INFINITY, -INFINITY, -INFINITY);
+    box.max = dmnsn_new_vector(INFINITY, INFINITY, INFINITY);
+    return box;
+  }
+
   dmnsn_vector corner;
   dmnsn_bounding_box ret;
   ret.min = dmnsn_matrix_vector_mul(trans, box.min);
-- 
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