From 2f0b1b3d9c4838bb066b7342de1d11b96945ac48 Mon Sep 17 00:00:00 2001
From: priseborough <p_riseborough@live.com.au>
Date: Sat, 3 Jan 2015 21:30:23 +1100
Subject: [PATCH] AP_NavEKF: Fix bug preventing use of optical flow without GPS

---
 libraries/AP_NavEKF/AP_NavEKF.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libraries/AP_NavEKF/AP_NavEKF.cpp b/libraries/AP_NavEKF/AP_NavEKF.cpp
index 866be00435..04eeecdc36 100644
--- a/libraries/AP_NavEKF/AP_NavEKF.cpp
+++ b/libraries/AP_NavEKF/AP_NavEKF.cpp
@@ -720,7 +720,7 @@ void NavEKF::UpdateFilter()
 void NavEKF::SelectVelPosFusion()
 {
     // check for new data, specify which measurements should be used and check data for freshness
-    if (!constPosMode && !constVelMode) {
+    if (PV_AidingMode == AID_ABSOLUTE) {
 
         // check for and read new GPS data
         readGpsData();