Cleaned up some love.graphics code.

--HG--
branch : minor

src/common/math.h

@@ -61,6 +61,17 @@
 namespace love
 {
 
+struct Rect
+{
+	int x, y;
+	int w, h;
+
+	bool operator == (const Rect &rhs) const
+	{
+		return x == rhs.x && y == rhs.y && w == rhs.w && h == rhs.h;
+	}
+};
+
 struct Vertex
 {
 	float x, y;