From 69da7e9f86a1e0ae3a1a7c50dd91a3f866cb484b Mon Sep 17 00:00:00 2001
From: Andrew Tridgell <andrew@tridgell.net>
Date: Fri, 22 Jul 2016 16:42:23 +1000
Subject: [PATCH] SITL: added elevrev option for plane sim

used by autotest
---
 libraries/SITL/SIM_Plane.cpp | 7 +++++++
 libraries/SITL/SIM_Plane.h   | 1 +
 2 files changed, 8 insertions(+)

diff --git a/libraries/SITL/SIM_Plane.cpp b/libraries/SITL/SIM_Plane.cpp
index 7e6a817239..f55bd0f087 100644
--- a/libraries/SITL/SIM_Plane.cpp
+++ b/libraries/SITL/SIM_Plane.cpp
@@ -47,6 +47,9 @@ Plane::Plane(const char *home_str, const char *frame_str) :
     } else if (strstr(frame_str, "-vtail")) {
         vtail = true;
     }
+    if (strstr(frame_str, "-elevrev")) {
+        reverse_elevator_rudder = true;
+    }
 
     ground_behavior = GROUND_BEHAVIOR_FWD_ONLY;
 }
@@ -205,6 +208,10 @@ void Plane::calculate_forces(const struct sitl_input &input, Vector3f &rot_accel
     float elevator = (input.servos[1]-1500)/500.0f;
     float rudder   = (input.servos[3]-1500)/500.0f;
     float throttle;
+    if (reverse_elevator_rudder) {
+        elevator = -elevator;
+        rudder = -rudder;
+    }
     if (elevons) {
         // fake an elevon plane
         float ch1 = aileron;
diff --git a/libraries/SITL/SIM_Plane.h b/libraries/SITL/SIM_Plane.h
index 2b6d0577af..2304c308b0 100644
--- a/libraries/SITL/SIM_Plane.h
+++ b/libraries/SITL/SIM_Plane.h
@@ -94,6 +94,7 @@ protected:
     bool reverse_thrust;
     bool elevons;
     bool vtail;
+    bool reverse_elevator_rudder;
 
     float liftCoeff(float alpha) const;
     float dragCoeff(float alpha) const;