From e9fbea9497eb0f1646b6535f5d9219673abf21ed Mon Sep 17 00:00:00 2001
From: Randy Mackay <rmackay9@yahoo.com>
Date: Wed, 13 Aug 2014 15:21:52 +0900
Subject: [PATCH] Baro: make get_altitude_difference const

---
 libraries/AP_Baro/AP_Baro.cpp | 2 +-
 libraries/AP_Baro/AP_Baro.h   | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/libraries/AP_Baro/AP_Baro.cpp b/libraries/AP_Baro/AP_Baro.cpp
index e4f40da04f..fe2e35d389 100644
--- a/libraries/AP_Baro/AP_Baro.cpp
+++ b/libraries/AP_Baro/AP_Baro.cpp
@@ -132,7 +132,7 @@ void AP_Baro::update_calibration()
 
 // return altitude difference in meters between current pressure and a
 // given base_pressure in Pascal
-float AP_Baro::get_altitude_difference(float base_pressure, float pressure)
+float AP_Baro::get_altitude_difference(float base_pressure, float pressure) const
 {
     float ret;
 #if HAL_CPU_CLASS <= HAL_CPU_CLASS_16
diff --git a/libraries/AP_Baro/AP_Baro.h b/libraries/AP_Baro/AP_Baro.h
index c1d49a9f37..684260a758 100644
--- a/libraries/AP_Baro/AP_Baro.h
+++ b/libraries/AP_Baro/AP_Baro.h
@@ -43,7 +43,7 @@ public:
 
     // get altitude difference in meters relative given a base
     // pressure in Pascal
-    float        get_altitude_difference(float base_pressure, float pressure);
+    float get_altitude_difference(float base_pressure, float pressure) const;
 
     // get scale factor required to convert equivalent to true airspeed
     float        get_EAS2TAS(void);