From 849f4aa735352704995ffb51bf23dadf795bb119 Mon Sep 17 00:00:00 2001
From: Dan Goodliffe <dan@randomdan.homeip.net>
Date: Tue, 13 Feb 2024 01:36:42 +0000
Subject: Include face handle in intersectRay result

---
 game/geoData.cpp | 8 ++++----
 game/geoData.h   | 6 ++++--
 2 files changed, 8 insertions(+), 6 deletions(-)

(limited to 'game')

diff --git a/game/geoData.cpp b/game/geoData.cpp
index ae43f3f..0dbc0ac 100644
--- a/game/geoData.cpp
+++ b/game/geoData.cpp
@@ -213,16 +213,16 @@ GeoData::positionAt(const PointFace & p) const
 	return positionOnTriangle(p.point, triangle<3>(p.face(this)));
 }
 
-[[nodiscard]] std::optional<GlobalPosition3D>
+[[nodiscard]] GeoData::IntersectionResult
 GeoData::intersectRay(const Ray<GlobalPosition3D> & ray) const
 {
 	return intersectRay(ray, findPoint(ray.start));
 }
 
-[[nodiscard]] std::optional<GlobalPosition3D>
+[[nodiscard]] GeoData::IntersectionResult
 GeoData::intersectRay(const Ray<GlobalPosition3D> & ray, FaceHandle face) const
 {
-	std::optional<GlobalPosition3D> out;
+	GeoData::IntersectionResult out;
 	walkUntil(PointFace {ray.start, face},
 			ray.start.xy()
 					+ GlobalPosition2D(ray.direction.xy() * RelativePosition2D(upperExtent.xy() - lowerExtent.xy())),
@@ -231,7 +231,7 @@ GeoData::intersectRay(const Ray<GlobalPosition3D> & ray, FaceHandle face) const
 				RelativeDistance dist {};
 				const auto t = triangle<3>(face);
 				if (ray.intersectTriangle(t.x, t.y, t.z, bari, dist)) {
-					out = t * bari;
+					out.emplace(t * bari, face);
 					return true;
 				}
 				return false;
diff --git a/game/geoData.h b/game/geoData.h
index 2fd3aa5..f599552 100644
--- a/game/geoData.h
+++ b/game/geoData.h
@@ -74,8 +74,10 @@ public:
 	[[nodiscard]] FaceHandle findPoint(GlobalPosition2D, FaceHandle start) const;
 
 	[[nodiscard]] GlobalPosition3D positionAt(const PointFace &) const;
-	[[nodiscard]] std::optional<GlobalPosition3D> intersectRay(const Ray<GlobalPosition3D> &) const;
-	[[nodiscard]] std::optional<GlobalPosition3D> intersectRay(const Ray<GlobalPosition3D> &, FaceHandle start) const;
+	using IntersectionLocation = std::pair<GlobalPosition3D, FaceHandle>;
+	using IntersectionResult = std::optional<IntersectionLocation>;
+	[[nodiscard]] IntersectionResult intersectRay(const Ray<GlobalPosition3D> &) const;
+	[[nodiscard]] IntersectionResult intersectRay(const Ray<GlobalPosition3D> &, FaceHandle start) const;
 
 	void walk(const PointFace & from, const GlobalPosition2D to, const std::function<void(FaceHandle)> & op) const;
 	void walkUntil(const PointFace & from, const GlobalPosition2D to, const std::function<bool(FaceHandle)> & op) const;
-- 
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