Link helper to get an End pointer based on position

3 files changed, 17 insertions, 0 deletions

diff --git a/game/network/link.cpp b/game/network/link.cpp
index b8ffee2..1a4bb89 100644
--- a/game/network/link.cpp
+++ b/game/network/link.cpp
@@ -7,6 +7,18 @@
 
 Link::Link(End endA, End endB, float len) : ends {{std::move(endA), std::move(endB)}}, length {len} { }
 
+const Link::End *
+Link::endAt(const GlobalPosition3D & queryPos) const
+{
+	if (ends.front().node->pos == queryPos) {
+		return &ends.front();
+	}
+	if (ends.back().node->pos == queryPos) {
+		return &ends.back();
+	}
+	return nullptr;
+}
+
 LinkCurve::LinkCurve(GlobalPosition3D centre, RelativeDistance radius, Arc arc) :
 	centreBase {centre}, radius {radius}, arc {std::move(arc)}
 {
diff --git a/game/network/link.h b/game/network/link.h
index 0b58558..7ef1387 100644
--- a/game/network/link.h
+++ b/game/network/link.h
@@ -48,6 +48,8 @@ public:
 	[[nodiscard]] virtual bool intersectRay(const Ray<GlobalPosition3D> &) const = 0;
 	[[nodiscard]] virtual std::vector<GlobalPosition3D> getBase(RelativeDistance width) const = 0;
 
+	[[nodiscard]] const End * endAt(const GlobalPosition3D &) const;
+
 	std::array<End, 2> ends;
 	float length;
 
diff --git a/test/test-network.cpp b/test/test-network.cpp
index 2b4b958..e6b92f3 100644
--- a/test/test-network.cpp
+++ b/test/test-network.cpp
@@ -331,6 +331,9 @@ BOOST_AUTO_TEST_CASE(NetworkCreateExtendeeCurve)
 		BOOST_CHECK_CLOSE(curve->ends.front().dir, -half_pi, 1);
 		BOOST_CHECK_CLOSE_VECI(curve->ends.back().node->pos, GlobalPosition3D(0, 1000, 0));
 		BOOST_CHECK_CLOSE(curve->ends.back().dir, -half_pi, 1);
+		BOOST_CHECK_EQUAL(curve->endAt(GlobalPosition3D(0, 0, 0)), &curve->ends.front());
+		BOOST_CHECK_EQUAL(curve->endAt(GlobalPosition3D(0, 1000, 0)), &curve->ends.back());
+		BOOST_CHECK(!curve->endAt(GlobalPosition3D(1000, 1000, 0)));
 	}
 
 	add(nullptr, link.front());