From 858b7058fb299c91c8f7590ab2eb9739dae1f1b7 Mon Sep 17 00:00:00 2001
From: Daniel2000815 <danizufrique@gmail.com>
Date: Thu, 8 Feb 2024 13:36:13 +0100
Subject: [PATCH 1/2] Added closest(line, line) and test

---
 TEST_Geometry2D.cpp  | 33 +++++++++++++++++++++++++++++++++
 olcUTIL_Geometry2D.h | 28 ++++++++++++++++++++++++++--
 2 files changed, 59 insertions(+), 2 deletions(-)

diff --git a/TEST_Geometry2D.cpp b/TEST_Geometry2D.cpp
index fbdb6ee..cbc4c87 100644
--- a/TEST_Geometry2D.cpp
+++ b/TEST_Geometry2D.cpp
@@ -132,6 +132,26 @@ class Test_Geometry2D : public olc::PixelGameEngine
 		return std::visit(dispatch, s1, s2);
 	}
 
+	olc::vf2d CheckClosest(const ShapeWrap& s1, const ShapeWrap& s2)
+	{
+		const auto dispatch = overloads{
+			[](const auto& lhs, const auto& rhs)
+			{
+				return closest(make_internal(lhs), make_internal(rhs));
+			},
+			// Discard not implemented
+			[](const Ray&, const auto&) { return olc::vf2d{}; },
+			[](const auto&, const Ray&) {return olc::vf2d{}; },
+			[](const Ray&, const Ray&) {return olc::vf2d{}; },
+			[](const Line&, const Rect&) {return olc::vf2d{}; },
+			[](const Rect&, const Rect&) {return olc::vf2d{}; },
+			[](const Circle&, const Rect&) {return olc::vf2d{}; },
+			[](const Triangle&, const Rect&) {return olc::vf2d{}; }
+		};
+
+		return std::visit(dispatch, s1, s2);
+	}
+
 	std::vector<olc::vf2d> CheckIntersects(const ShapeWrap& s1, const ShapeWrap& s2)
 	{
 		const auto dispatch = overloads{
@@ -294,6 +314,7 @@ class Test_Geometry2D : public olc::PixelGameEngine
 		std::vector<size_t> vContains;
 		std::vector<size_t> vOverlaps;
 		std::vector<olc::vf2d> vIntersections;
+		std::vector<olc::vf2d> vClosestsPoints;
 		if (nSelectedShapeIndex < vecShapes.size())
 		{
 			for (size_t i = 0; i < vecShapes.size(); i++)
@@ -310,6 +331,13 @@ class Test_Geometry2D : public olc::PixelGameEngine
 
 				if (CheckOverlaps(vecShapes[nSelectedShapeIndex], vTargetShape))
 					vOverlaps.push_back(i);
+
+				olc::v_2d<float> c = CheckClosest(vecShapes[nSelectedShapeIndex], vTargetShape);
+				if (c.mag() > 0.f) {
+					vClosestsPoints.push_back(c);
+					vClosestsPoints.push_back(CheckClosest(vTargetShape, vecShapes[nSelectedShapeIndex]));
+				}
+				
 			}
 		}
 
@@ -369,6 +397,11 @@ class Test_Geometry2D : public olc::PixelGameEngine
 		for (const auto& intersection : vIntersections)
 			FillCircle(intersection, 3, olc::RED);
 
+		// Draw Closests
+		for (auto i = 0; i < vClosestsPoints.size()/2; i++)
+			DrawLine(vClosestsPoints[2 * i], vClosestsPoints[2 * i + 1], olc::DARK_GREY);
+
+
 		if (bRayMode)
 		{
 			DrawShape(ray1, olc::CYAN); 
diff --git a/olcUTIL_Geometry2D.h b/olcUTIL_Geometry2D.h
index 7e3be8a..8b61504 100644
--- a/olcUTIL_Geometry2D.h
+++ b/olcUTIL_Geometry2D.h
@@ -191,6 +191,7 @@
 #include <optional>
 #include <cassert>
 #include <array>
+#include <iostream>
 
 #ifndef OLC_V2D_TYPE
 #define OLC_V2D_TYPE
@@ -895,8 +896,31 @@ namespace olc::utils::geom2d
 	template<typename T1, typename T2>
 	inline olc::v_2d<T1> closest(const line<T1>& l1, const line<T2>& l2)
 	{
-		// TODO:
-		return {};
+		auto V1 = l1.end - l1.start;
+		auto V2 = l2.end - l2.start;
+		auto V21 = l2.start - l1.start;
+
+		auto v22 = V2.dot(V2);
+		auto v11 = V1.dot(V1);
+		auto v21 = V2.dot(V1);
+		auto v21_1 = V21.dot(V1);
+		auto v21_2 = V21.dot(V2);
+		auto denom = v21 * v21 - v22 * v11;
+
+		float s, t;
+		if (denom == 0.f) {
+			s = 0.f;
+			t = (v11 * s - v21_1) / v21;
+		}
+		else {
+			s = (v21_2 * v21 - v22 * v21_1) / denom;
+			t = (-v21_1 * v21 + v11 * v21_2) / denom;
+		}
+
+		s = std::max(std::min(s, 1.f), 0.f);
+		t = std::max(std::min(t, 1.f), 0.f);
+
+		return l1.start + s * V1;
 	}
 
 	// closest(r,l)

From 67c0ace208da1d8957833d468860064345ec4258 Mon Sep 17 00:00:00 2001
From: Daniel2000815 <danizufrique@gmail.com>
Date: Thu, 8 Feb 2024 16:19:06 +0100
Subject: [PATCH 2/2] Remove iostream include

---
 olcUTIL_Geometry2D.h | 1 -
 1 file changed, 1 deletion(-)

diff --git a/olcUTIL_Geometry2D.h b/olcUTIL_Geometry2D.h
index 8b61504..6add43e 100644
--- a/olcUTIL_Geometry2D.h
+++ b/olcUTIL_Geometry2D.h
@@ -191,7 +191,6 @@
 #include <optional>
 #include <cassert>
 #include <array>
-#include <iostream>
 
 #ifndef OLC_V2D_TYPE
 #define OLC_V2D_TYPE