From 29776f836677f37c5eeafb727c9a7fbfd52029f9 Mon Sep 17 00:00:00 2001
From: Kelvin Sherlock <ksherlock@gmail.com>
Date: Thu, 16 Feb 2017 00:26:01 +0000
Subject: [PATCH] iRect operators.

git-svn-id: svn://qnap.local/TwoTerm/branches/fix-gno-scrolling-region@3161 5590a31f-7b70-45f8-8c82-aa3a8e5f4507
---
 cpp/iGeometry.cpp | 19 +++++++++++++++++--
 cpp/iGeometry.h   | 25 +++++++++++++++++++++----
 2 files changed, 38 insertions(+), 6 deletions(-)

diff --git a/cpp/iGeometry.cpp b/cpp/iGeometry.cpp
index 99d3bbd..5c685f5 100644
--- a/cpp/iGeometry.cpp
+++ b/cpp/iGeometry.cpp
@@ -9,7 +9,7 @@
 
 
 #include "iGeometry.h"
-
+#include <algorithm>
 
 bool iRect::contains(const iPoint aPoint) const
 {
@@ -30,4 +30,19 @@ bool iRect::contains(const iRect aRect) const
 bool iRect::intersects(const iRect aRect) const
 {
     return aRect.contains(origin) || aRect.contains(origin.offset(size));    
-}
\ No newline at end of file
+}
+
+iRect iRect::intersection(const iRect &rhs) const {
+    iPoint topLeft;
+    iPoint bottomRight;
+    topLeft.x = std::max(origin.x, rhs.origin.x);
+    topLeft.y = std::max(origin.y, rhs.origin.y);
+
+    bottomRight.x = std::min(maxX(), rhs.maxX());
+    bottomRight.y = std::min(maxY(), rhs.maxY());
+    
+    if (bottomRight.x <= topLeft.x) return iRect();
+    if (bottomRight.y <= topLeft.y) return iRect();
+    
+    return iRect(topLeft, bottomRight);
+}
diff --git a/cpp/iGeometry.h b/cpp/iGeometry.h
index 9bc89ec..7aac4a6 100644
--- a/cpp/iGeometry.h
+++ b/cpp/iGeometry.h
@@ -23,10 +23,10 @@ typedef struct iSize {
     
     iSize &operator=(const iSize &) = default;
 
-    bool operator==(const iSize &aSize)
+    bool operator==(const iSize &aSize) const
     { return width == aSize.width && height == aSize.height; }
     
-    bool operator!=(const iSize& aSize)
+    bool operator!=(const iSize& aSize) const
     { return !(*this == aSize); }
     
 } iSize;
@@ -43,10 +43,10 @@ typedef struct iPoint {
     
     iPoint &operator=(const iPoint &) = default;
     
-    bool operator==(const iPoint &aPoint)
+    bool operator==(const iPoint &aPoint) const
     { return x == aPoint.x && y == aPoint.y; }
     
-    bool operator!=(const iPoint &aPoint)
+    bool operator!=(const iPoint &aPoint) const
     { return !(*this == aPoint); }
     
     iPoint offset(int dx, int dy) const
@@ -80,6 +80,23 @@ typedef struct iRect {
     
     bool intersects(const iRect aRect) const;
     
+    iRect intersection(const iRect &rhs) const;
+    
+    bool operator==(const iRect &rhs) const {
+        return origin == rhs.origin && size == rhs.size;
+    }
+    bool operator!=(const iRect &rhs) const {
+        return !(*this == rhs);
+    }
+    
+    explicit operator bool() const { return size.height >= 0 && size.width >= 0; }
+    bool operator!() const { return size.height < 0 || size.width < 0; }
+    bool valid() const { return size.height >= 0 && size.width >= 0; }
+    
+    iPoint topLeft() const { return origin; }
+    iPoint bottomRight() const { return iPoint(maxX(), maxY()); }
+    
+    void setBottomLeft(iPoint &p);
     
     int height() const
     { return size.height; }