From 8e6bf5fc2fb2f466c39b63283b5d408eff68e32a Mon Sep 17 00:00:00 2001
From: Dmitry Marakasov <amdmi3@amdmi3.ru>
Date: Fri, 21 Feb 2014 20:09:11 +0400
Subject: [PATCH] Add basic Point arith

---
 SDL2pp/Point.cc         | 34 ++++++++++++++++++++++++++++++++++
 SDL2pp/Point.hh         |  6 ++++++
 tests/test_pointrect.cc | 28 ++++++++++++++++++++++++++++
 3 files changed, 68 insertions(+)

diff --git a/SDL2pp/Point.cc b/SDL2pp/Point.cc
index d3c9cd1..d36f005 100644
--- a/SDL2pp/Point.cc
+++ b/SDL2pp/Point.cc
@@ -82,4 +82,38 @@ void Point::SetY(int y) {
 	point_.y = y;
 }
 
+Point Point::operator+(const Point& other) const {
+	if (!valid_ || !other.valid_)
+		return Point();
+	return Point(point_.x + other.point_.x, point_.y + other.point_.y);
+}
+
+Point Point::operator-(const Point& other) const {
+	if (!valid_ || !other.valid_)
+		return Point();
+	return Point(point_.x - other.point_.x, point_.y - other.point_.y);
+}
+
+Point& Point::operator+=(const Point& other) {
+	if (!valid_ || !other.valid_) {
+		valid_ = false;
+	} else {
+		point_.x += other.point_.x;
+		point_.y += other.point_.y;
+	}
+
+	return *this;
+}
+
+Point& Point::operator-=(const Point& other) {
+	if (!valid_ || !other.valid_) {
+		valid_ = false;
+	} else {
+		point_.x -= other.point_.x;
+		point_.y -= other.point_.y;
+	}
+
+	return *this;
+}
+
 }
diff --git a/SDL2pp/Point.hh b/SDL2pp/Point.hh
index 31d34e9..568fc67 100644
--- a/SDL2pp/Point.hh
+++ b/SDL2pp/Point.hh
@@ -58,6 +58,12 @@ public:
 
 	int GetY() const;
 	void SetY(int y);
+
+	Point operator+(const Point& other) const;
+	Point operator-(const Point& other) const;
+
+	Point& operator+=(const Point& other);
+	Point& operator-=(const Point& other);
 };
 
 }
diff --git a/tests/test_pointrect.cc b/tests/test_pointrect.cc
index a5378d2..ebfd627 100644
--- a/tests/test_pointrect.cc
+++ b/tests/test_pointrect.cc
@@ -55,6 +55,34 @@ BEGIN_TEST()
 		EXPECT_TRUE(p.GetX() == 14 && p.GetY() == 15);
 	}
 
+	{
+		// Point arith
+		Point sum = Point(1, 2) + Point(10, 20);
+		Point diff = Point(-1, -2) - Point(10, 20);
+
+		EXPECT_TRUE(sum.GetX() == 11 && sum.GetY() == 22);
+		EXPECT_TRUE(diff.GetX() == -11 && diff.GetY() == -22);
+
+		sum += Point(100, 200);
+		diff -= Point(100, 200);
+
+		EXPECT_TRUE(sum.GetX() == 111 && sum.GetY() == 222);
+		EXPECT_TRUE(diff.GetX() == -111 && diff.GetY() == -222);
+
+		sum += Point::Null();
+		diff -= Point::Null();
+
+		EXPECT_TRUE(sum.IsNull());
+		EXPECT_TRUE(diff.IsNull());
+
+		EXPECT_TRUE((Point(1,1) + Point::Null()).IsNull());
+		EXPECT_TRUE((Point(1,1) - Point::Null()).IsNull());
+		EXPECT_TRUE((Point::Null() + Point(1,1)).IsNull());
+		EXPECT_TRUE((Point::Null() - Point(1,1)).IsNull());
+		EXPECT_TRUE((Point::Null() - Point::Null()).IsNull());
+		EXPECT_TRUE((Point::Null() - Point::Null()).IsNull());
+	}
+
 	{
 		// Rect basic ops
 		Rect r(1,2,3,4);