From ced4e1e0e0b10aee5c8c1e37af6507a1e662612b Mon Sep 17 00:00:00 2001
From: luiscuenca <luiscuenca@outboxcode.com>
Date: Wed, 11 Jul 2018 18:02:19 -0700
Subject: [PATCH] Fix blue screen after player step returns NaN values

---
 libraries/physics/src/CharacterController.cpp | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/libraries/physics/src/CharacterController.cpp b/libraries/physics/src/CharacterController.cpp
index aaf2c0a46b..0bbfa41a12 100755
--- a/libraries/physics/src/CharacterController.cpp
+++ b/libraries/physics/src/CharacterController.cpp
@@ -277,10 +277,14 @@ void CharacterController::playerStep(btCollisionWorld* collisionWorld, btScalar
         btVector3 shapeLocalOffset = glmToBullet(_shapeLocalOffset);
         btVector3 swingDisplacement = rotateVector(endRot, -shapeLocalOffset) - rotateVector(startRot, -shapeLocalOffset);
 
-        _followLinearDisplacement = linearDisplacement + swingDisplacement + _followLinearDisplacement;
-        _followAngularDisplacement = angularDisplacement * _followAngularDisplacement;
+        if (!isNaN(bulletToGLM(endPos)) && !isNaN(bulletToGLM(endRot))) {
+            _followLinearDisplacement = linearDisplacement + swingDisplacement + _followLinearDisplacement;
+            _followAngularDisplacement = angularDisplacement * _followAngularDisplacement;
 
-        _rigidBody->setWorldTransform(btTransform(endRot, endPos));
+            _rigidBody->setWorldTransform(btTransform(endRot, endPos));
+        } else {
+            qCWarning(physics) << "CharacterController::playerStep produced NaN.";
+        }
     }
     _followTime += dt;