From a1624af969f9cf07e2056f2399b999396f86f3af Mon Sep 17 00:00:00 2001
From: Lynix <lynix680@gmail.com>
Date: Sat, 3 Jan 2015 22:15:15 +0100
Subject: [PATCH] Improved [Box|Rect]::Intersect performances

Allowed early returns


Former-commit-id: 59001afdd9734666640d440cb8b87b5a426973ce
---
 include/Nazara/Math/Box.inl  | 35 +++++++++++++++++++----------------
 include/Nazara/Math/Rect.inl | 34 +++++++++++++++++-----------------
 2 files changed, 36 insertions(+), 33 deletions(-)

diff --git a/include/Nazara/Math/Box.inl b/include/Nazara/Math/Box.inl
index 744d513ab..651a6de13 100644
--- a/include/Nazara/Math/Box.inl
+++ b/include/Nazara/Math/Box.inl
@@ -247,27 +247,30 @@ bool NzBox<T>::Intersect(const NzBox& box, NzBox* intersection) const
 {
 	T left = std::max(x, box.x);
 	T right = std::min(x + width, box.x + box.width);
+	if (left >= right)
+		return false;
+
 	T top = std::max(y, box.y);
 	T bottom = std::min(y + height, box.y + box.height);
+	if (top >= bottom)
+		return false;
+
 	T up = std::max(z, box.z);
 	T down = std::min(z + depth, box.z + box.depth);
-
-	if (left < right && top < bottom && up < down)
-	{
-		if (intersection)
-		{
-			intersection->x = left;
-			intersection->y = top;
-			intersection->z = up;
-			intersection->width = right - left;
-			intersection->height = bottom - top;
-			intersection->depth = down - up;
-		}
-
-		return true;
-	}
-	else
+	if (up >= down)
 		return false;
+
+	if (intersection)
+	{
+		intersection->x = left;
+		intersection->y = top;
+		intersection->z = up;
+		intersection->width = right - left;
+		intersection->height = bottom - top;
+		intersection->depth = down - up;
+	}
+
+	return true;
 }
 
 template<typename T>
diff --git a/include/Nazara/Math/Rect.inl b/include/Nazara/Math/Rect.inl
index 611403706..3d1908b83 100644
--- a/include/Nazara/Math/Rect.inl
+++ b/include/Nazara/Math/Rect.inl
@@ -166,24 +166,24 @@ template<typename T>
 bool NzRect<T>::Intersect(const NzRect& rect, NzRect* intersection) const
 {
 	T left = std::max(x, rect.x);
-	T right = std::min(x+width, rect.x+rect.width);
-	T top = std::max(y, rect.y);
-	T bottom = std::min(y+height, rect.y+rect.height);
-
-	if (left < right && top < bottom)
-	{
-		if (intersection)
-		{
-			intersection->x = left;
-			intersection->y = top;
-			intersection->width = right-left;
-			intersection->height = bottom-top;
-		}
-
-		return true;
-	}
-	else
+	T right = std::min(x + width, rect.x + rect.width);
+	if (left >= right)
 		return false;
+
+	T top = std::max(y, rect.y);
+	T bottom = std::min(y + height, rect.y + rect.height);
+	if (top >= bottom)
+		return false;
+
+	if (intersection)
+	{
+		intersection->x = left;
+		intersection->y = top;
+		intersection->width = right - left;
+		intersection->height = bottom - top;
+	}
+
+	return true;
 }
 
 template<typename T>