From 7883085e4aae830558137ba085c6385bb1fb7b8e Mon Sep 17 00:00:00 2001
From: Daniel Agar <daniel@agar.ca>
Date: Thu, 2 Feb 2017 00:17:43 -0500
Subject: [PATCH] clang-tidy readability-simplify-boolean-expr (#235)

---
 EKF/ekf.cpp               |  7 +------
 EKF/gps_checks.cpp        | 13 ++-----------
 EKF/terrain_estimator.cpp |  7 +------
 3 files changed, 4 insertions(+), 23 deletions(-)

diff --git a/EKF/ekf.cpp b/EKF/ekf.cpp
index bdc3c0889f..f98e7a3a0b 100644
--- a/EKF/ekf.cpp
+++ b/EKF/ekf.cpp
@@ -237,12 +237,7 @@ bool Ekf::update()
 	}
 
 	// We don't have valid data to output until tilt and yaw alignment is complete
-	if (_control_status.flags.tilt_align && _control_status.flags.yaw_align) {
-		return true;
-
-	} else {
-		return false;
-	}
+	return _control_status.flags.tilt_align && _control_status.flags.yaw_align;
 }
 
 bool Ekf::initialiseFilter()
diff --git a/EKF/gps_checks.cpp b/EKF/gps_checks.cpp
index 952987879c..29d83281f7 100644
--- a/EKF/gps_checks.cpp
+++ b/EKF/gps_checks.cpp
@@ -98,12 +98,7 @@ bool Ekf::collect_gps(uint64_t time_usec, struct gps_message *gps)
 	}
 
 	// start collecting GPS if there is a 3D fix and the NED origin has been set
-	if (_NED_origin_initialised && gps->fix_type >= 3) {
-		return true;
-
-	} else {
-		return false;
-	}
+	return _NED_origin_initialised && (gps->fix_type >= 3);
 
 	return false;
 }
@@ -239,10 +234,6 @@ bool Ekf::gps_is_good(struct gps_message *gps)
 	}
 
 	// continuous period without fail of 10 seconds required to return a healthy status
-	if (_time_last_imu - _last_gps_fail_us > 1e7) {
-		return true;
-	}
-
-	return false;
+	return (_time_last_imu - _last_gps_fail_us > 1e7);
 }
 
diff --git a/EKF/terrain_estimator.cpp b/EKF/terrain_estimator.cpp
index 7c91cf9262..b337005174 100644
--- a/EKF/terrain_estimator.cpp
+++ b/EKF/terrain_estimator.cpp
@@ -138,12 +138,7 @@ bool Ekf::get_terrain_vert_pos(float *ret)
 	// The height is useful if the uncertainty in terrain height is significantly smaller than than the estimated height above terrain
 	bool accuracy_useful = (sqrtf(_terrain_var) < 0.2f * fmaxf((_terrain_vpos - _state.pos(2)), _params.rng_gnd_clearance));
 
-	if (_time_last_imu - _time_last_hagl_fuse < 1e6 || accuracy_useful) {
-		return true;
-
-	} else {
-		return false;
-	}
+	return (_time_last_imu - _time_last_hagl_fuse < 1e6) || accuracy_useful;
 }
 
 void Ekf::get_hagl_innov(float *hagl_innov)