From 015519cf2319c0c9b28f9e4197b1014678d9cc50 Mon Sep 17 00:00:00 2001
From: Damon Kohler <damonkohler@google.com>
Date: Mon, 21 Nov 2016 17:28:50 +0100
Subject: [PATCH] Adds support for inverted LaserScan messages. (#138)

---
 cartographer/sensor/laser.cc | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/cartographer/sensor/laser.cc b/cartographer/sensor/laser.cc
index 6015183..d5ce47f 100644
--- a/cartographer/sensor/laser.cc
+++ b/cartographer/sensor/laser.cc
@@ -40,8 +40,11 @@ std::vector<uint8> ReorderReflectivities(
 PointCloud ToPointCloud(const proto::LaserScan& proto) {
   CHECK_GE(proto.range_min(), 0.f);
   CHECK_GE(proto.range_max(), proto.range_min());
-  CHECK_GT(proto.angle_increment(), 0.f);
-  CHECK_GT(proto.angle_max(), proto.angle_min());
+  if (proto.angle_increment() > 0.f) {
+    CHECK_GT(proto.angle_max(), proto.angle_min());
+  } else {
+    CHECK_GT(proto.angle_min(), proto.angle_max());
+  }
   PointCloud point_cloud;
   float angle = proto.angle_min();
   for (const auto& range : proto.range()) {