Add helper constructors to Arc

* Two angles, wraps logic ensuring b after a
* Two vector directions
* Centre and two endpoints, in at least 2 dimensions, uses .xy()

5 files changed, 20 insertions, 26 deletions

diff --git a/game/geoData.cpp b/game/geoData.cpp
index f4d9f65..aaa2548 100644
--- a/game/geoData.cpp
+++ b/game/geoData.cpp
@@ -453,7 +453,7 @@ GeoData::setHeights(const std::span<const GlobalPosition3D> triangleStrip)
 			return extrusionDir;
 		};
 		// Previous half edge end to current half end start arc tangents
-		const Arc arc {p1, p1 + (e0 || 0.F), p1 + (e1 || 0.F)};
+		const Arc arc {e0, e1};
 		const auto limit = std::floor((arc.second - arc.first) * 5.F / pi);
 		const auto inc = (arc.second - arc.first) / limit;
 		for (float step = 1; step < limit; step += 1.F) {
diff --git a/game/network/rail.cpp b/game/network/rail.cpp
index e342224..fd07ace 100644
--- a/game/network/rail.cpp
+++ b/game/network/rail.cpp
@@ -95,9 +95,8 @@ round_sleepers(const float v)
 	return round_frac(v, sleepers);
 }
 
-RailLinkStraight::RailLinkStraight(
-		NetworkLinkHolder<RailLinkStraight> & instances, const Node::Ptr & a, const Node::Ptr & b) :
-	RailLinkStraight(instances, a, b, b->pos - a->pos)
+RailLinkStraight::RailLinkStraight(NetworkLinkHolder<RailLinkStraight> & instances, const Node::Ptr & a,
+		const Node::Ptr & b) : RailLinkStraight(instances, a, b, b->pos - a->pos)
 {
 }
 
@@ -109,9 +108,8 @@ RailLinkStraight::RailLinkStraight(
 {
 }
 
-RailLinkCurve::RailLinkCurve(
-		NetworkLinkHolder<RailLinkCurve> & instances, const Node::Ptr & a, const Node::Ptr & b, GlobalPosition2D c) :
-	RailLinkCurve(instances, a, b, c || a->pos.z, {c || 0, a->pos, b->pos})
+RailLinkCurve::RailLinkCurve(NetworkLinkHolder<RailLinkCurve> & instances, const Node::Ptr & a, const Node::Ptr & b,
+		GlobalPosition2D c) : RailLinkCurve(instances, a, b, c || a->pos.z, {c, a->pos, b->pos})
 {
 }
 
diff --git a/lib/maths.cpp b/lib/maths.cpp
index bf17204..51e27fe 100644
--- a/lib/maths.cpp
+++ b/lib/maths.cpp
@@ -4,6 +4,11 @@
 #include <glm/gtx/rotate_vector.hpp>
 #include <glm/gtx/transform.hpp>
 
+Arc::Arc(const RelativePosition2D & dir0, const RelativePosition2D & dir1) :
+	Arc {vector_yaw(dir0), vector_yaw(dir1)} { }
+
+Arc::Arc(const Angle anga, const Angle angb) : pair {anga, (angb < anga) ? angb + two_pi : angb} { }
+
 glm::mat4
 flat_orientation(const Direction3D & diff)
 {
diff --git a/lib/maths.h b/lib/maths.h
index 20a397b..656fefd 100644
--- a/lib/maths.h
+++ b/lib/maths.h
@@ -8,11 +8,16 @@
 #include <stdexcept>
 #include <utility>
 
-struct Arc : public std::pair<float, float> {
-	using std::pair<float, float>::pair;
+struct Arc : public std::pair<Angle, Angle> {
+	template<glm::length_t Lc, glm::length_t Le, typename T, glm::qualifier Q>
+		requires(Lc >= 2, Le >= 2)
+	Arc(const glm::vec<Lc, T, Q> & centre, const glm::vec<Le, T, Q> & e0p, const glm::vec<Le, T, Q> & e1p) :
+		Arc {RelativePosition2D {e0p.xy() - centre.xy()}, RelativePosition2D {e1p.xy() - centre.xy()}}
+	{
+	}
 
-	template<typename T, glm::qualifier Q>
-	Arc(const glm::vec<3, T, Q> & centre3, const glm::vec<3, T, Q> & e0p, const glm::vec<3, T, Q> & e1p);
+	Arc(const RelativePosition2D & dir0, const RelativePosition2D & dir1);
+	Arc(const Angle angb, const Angle anga);
 
 	auto
 	operator[](bool i) const
@@ -244,21 +249,6 @@ midpoint(const std::pair<T, T> & v)
 	return std::midpoint(v.first, v.second);
 }
 
-template<typename T, glm::qualifier Q>
-Arc::Arc(const glm::vec<3, T, Q> & centre3, const glm::vec<3, T, Q> & e0p, const glm::vec<3, T, Q> & e1p) :
-	Arc([&]() -> Arc {
-		const auto diffa = e0p - centre3;
-		const auto diffb = e1p - centre3;
-		const auto anga = vector_yaw(diffa);
-		const auto angb = [&diffb, &anga]() {
-			const auto angb = vector_yaw(diffb);
-			return (angb < anga) ? angb + two_pi : angb;
-		}();
-		return {anga, angb};
-	}())
-{
-}
-
 // Conversions
 template<typename T>
 inline constexpr auto
diff --git a/test/Jamfile.jam b/test/Jamfile.jam
index 1b07b5a..cce4513 100644
--- a/test/Jamfile.jam
+++ b/test/Jamfile.jam
@@ -12,6 +12,7 @@ project : requirements
 	<define>BOOST_TEST_DYN_LINK
 	<define>RESDIR=\\\"$(res)/\\\"
 	<define>FIXTURESDIR=\\\"$(fixtures)/\\\"
+	<define>GLM_FORCE_SWIZZLE
 	<variant>debug:<warnings>pedantic
 	<variant>debug:<warnings-as-errors>on
 	<variant>debug:<cflags>-Wnon-virtual-dtor