From 547d7a5f23e2f2a06ff053d2ce7927a914d7fdb0 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Martin=20T=C5=AFma?= <tumic@cbox.cz>
Date: Thu, 3 Dec 2020 21:12:41 +0100
Subject: [PATCH] Fix the POI search algorithm (At least so, that it does not
 trigger the rtree assert. The whole RectC logic has to be fixed to properly
 handle poles/dateline "overflows")

---
 src/common/rectc.cpp | 17 +++++++++++++++++
 src/common/rectc.h   |  1 +
 src/data/poi.cpp     | 41 +++++++++++++++++++++--------------------
 3 files changed, 39 insertions(+), 20 deletions(-)

diff --git a/src/common/rectc.cpp b/src/common/rectc.cpp
index 9cd42daf..fa651115 100644
--- a/src/common/rectc.cpp
+++ b/src/common/rectc.cpp
@@ -1,3 +1,4 @@
+#include <cmath>
 #include "wgs84.h"
 #include "rectc.h"
 
@@ -6,6 +7,16 @@
 #define MIN_LON deg2rad(-180.0)
 #define MAX_LON deg2rad(180.0)
 
+static inline double WLON(double lon)
+{
+	return remainder(lon, 360.0);
+}
+
+static inline double LLAT(double lat)
+{
+	return (lat < 0.0) ? qMax(lat, -90.0) : qMin(lat, 90.0);
+}
+
 RectC::RectC(const Coordinates &center, double radius)
 {
 	double radDist = radius / WGS84_RADIUS;
@@ -151,6 +162,12 @@ RectC RectC::united(const Coordinates &c) const
 	return RectC(Coordinates(l, t), Coordinates(r, b));
 }
 
+RectC RectC::adjusted(double lon1, double lat1, double lon2, double lat2) const
+{
+	return RectC(Coordinates(WLON(_tl.lon() + lon1), LLAT(_tl.lat() + lat1)),
+	  Coordinates(WLON(_br.lon() + lon2), LLAT(_br.lat() + lat2)));
+}
+
 #ifndef QT_NO_DEBUG
 QDebug operator<<(QDebug dbg, const RectC &rect)
 {
diff --git a/src/common/rectc.h b/src/common/rectc.h
index abdbf4b2..f10191b9 100644
--- a/src/common/rectc.h
+++ b/src/common/rectc.h
@@ -40,6 +40,7 @@ public:
 	RectC &operator&=(const RectC &r) {*this = *this & r; return *this;}
 
 	RectC united(const Coordinates &c) const;
+	RectC adjusted(double lon1, double lat1, double lon2, double lat2) const;
 
 	bool intersects(const RectC &r) const
 	  {return (right() >= r.left() && bottom() <= r.top() && left() <= r.right()
diff --git a/src/data/poi.cpp b/src/data/poi.cpp
index 7d16afa5..d535e7e1 100644
--- a/src/data/poi.cpp
+++ b/src/data/poi.cpp
@@ -80,12 +80,25 @@ void POI::search(const RectC &rect, QSet<int> &set) const
 {
 	qreal min[2], max[2];
 
-	min[0] = rect.topLeft().lon();
-	min[1] = rect.bottomRight().lat();
-	max[0] = rect.bottomRight().lon();
-	max[1] = rect.topLeft().lat();
+	if (rect.left() > rect.right()) {
+		min[0] = rect.topLeft().lon();
+		min[1] = rect.bottomRight().lat();
+		max[0] = 180.0;
+		max[1] = rect.topLeft().lat();
+		_tree.Search(min, max, cb, &set);
 
-	_tree.Search(min, max, cb, &set);
+		min[0] = -180.0;
+		min[1] = rect.bottomRight().lat();
+		max[0] = rect.bottomRight().lon();
+		max[1] = rect.topLeft().lat();
+		_tree.Search(min, max, cb, &set);
+	} else {
+		min[0] = rect.topLeft().lon();
+		min[1] = rect.bottomRight().lat();
+		max[0] = rect.bottomRight().lon();
+		max[1] = rect.topLeft().lat();
+		_tree.Search(min, max, cb, &set);
+	}
 }
 
 QList<Waypoint> POI::points(const Path &path) const
@@ -130,16 +143,10 @@ QList<Waypoint> POI::points(const Waypoint &point) const
 {
 	QList<Waypoint> ret;
 	QSet<int> set;
-	qreal min[2], max[2];
 	QSet<int>::const_iterator it;
 
 	RectC br(point.coordinates(), _radius);
-	min[0] = br.topLeft().lon();
-	min[1] = br.bottomRight().lat();
-	max[0] = br.bottomRight().lon();
-	max[1] = br.topLeft().lat();
-
-	_tree.Search(min, max, cb, &set);
+	search(br, set);
 
 	for (it = set.constBegin(); it != set.constEnd(); ++it)
 		ret.append(_data.at(*it));
@@ -150,18 +157,12 @@ QList<Waypoint> POI::points(const Waypoint &point) const
 QList<Waypoint> POI::points(const RectC &rect) const
 {
 	QList<Waypoint> ret;
-	qreal min[2], max[2];
 	QSet<int> set;
 	QSet<int>::const_iterator it;
 
 	double offset = rad2deg(_radius / WGS84_RADIUS);
-
-	min[0] = rect.topLeft().lon() - offset;
-	min[1] = rect.bottomRight().lat() - offset;
-	max[0] = rect.bottomRight().lon() + offset;
-	max[1] = rect.topLeft().lat() + offset;
-
-	_tree.Search(min, max, cb, &set);
+	RectC br(rect.adjusted(-offset, offset, offset, -offset));
+	search(br, set);
 
 	for (it = set.constBegin(); it != set.constEnd(); ++it)
 		ret.append(_data.at(*it));