From: Tim Moore <timoore@redhat.com>
Date: Sun, 18 Jan 2009 23:04:59 +0000 (+0100)
Subject: Protect against division by zero in QuadTreeBuilder
X-Git-Url: https://git.mxchange.org/?a=commitdiff_plain;h=1a8fd626803635c7edf0647fbdb4be30d32572aa;p=simgear.git

Protect against division by zero in QuadTreeBuilder

This could only happen when there's one leaf in the tree, or all the objects
happen to have the same position. Noticed by Csaba Halaz
---

diff --git a/simgear/scene/util/QuadTreeBuilder.hxx b/simgear/scene/util/QuadTreeBuilder.hxx
index 2c5c4bf5..62734e3b 100644
--- a/simgear/scene/util/QuadTreeBuilder.hxx
+++ b/simgear/scene/util/QuadTreeBuilder.hxx
@@ -80,10 +80,14 @@ public:
     {
         using namespace osg;
         const Vec3 center(_getLocalCoords(obj));
-        int x = (int)(_dimension * (center.x() - _min.x())
+        int x = 0;
+        if (_max.x() != _min.x())
+            x = (int)(_dimension * (center.x() - _min.x())
                       / (_max.x() - _min.x()));
         x = clampTo(x, 0, (_dimension - 1));
-        int y = (int)(_dimension * (center.y() - _min.y())
+        int y = 0;
+        if (_max.y() != _min.y())
+            y = (int)(_dimension * (center.y() - _min.y())
                       / (_max.y() - _min.y()));
         y = clampTo(y, 0, (_dimension -1));
         _addLeafObject(_leaves(y, x), obj);