Supporters update.

[dcpomatic.git] / src / lib / rect.h

diff --git a/src/lib/rect.h b/src/lib/rect.h
index 6f4709c088ce137b2c589df64cb69304c1b62373..a01e0f8858ffba6d31eb6b9675d0cff571b4571d 100644 (file)
--- a/src/lib/rect.h
+++ b/src/lib/rect.h
@@ -1,40 +1,47 @@
 /*
-    Copyright (C) 2013 Carl Hetherington <cth@carlh.net>
+    Copyright (C) 2013-2021 Carl Hetherington <cth@carlh.net>
 
-    This program is free software; you can redistribute it and/or modify
+    This file is part of DCP-o-matic.
+
+    DCP-o-matic is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
     the Free Software Foundation; either version 2 of the License, or
     (at your option) any later version.
 
-    This program is distributed in the hope that it will be useful,
+    DCP-o-matic is distributed in the hope that it will be useful,
     but WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     GNU General Public License for more details.
 
     You should have received a copy of the GNU General Public License
-    along with this program; if not, write to the Free Software
-    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+    along with DCP-o-matic.  If not, see <http://www.gnu.org/licenses/>.
 
 */
 
+
 #ifndef DCPOMATIC_RECT_H
 #define DCPOMATIC_RECT_H
 
+
 #include "position.h"
+#include <boost/optional.hpp>
+#include <algorithm>
+
 
 /* Put this inside a namespace as Apple put a Rect in the global namespace */
 
 namespace dcpomatic
 {
-       
+
+
 /** @struct Rect
  *  @brief A rectangle.
  */
-template <class T>     
+template <class T>
 class Rect
 {
 public:
-       
+
        Rect ()
                : x (0)
                , y (0)
@@ -42,6 +49,13 @@ public:
                , height (0)
        {}
 
+       Rect (Position<T> p, T w_, T h_)
+               : x (p.x)
+               , y (p.y)
+               , width (w_)
+               , height (h_)
+       {}
+
        Rect (T x_, T y_, T w_, T h_)
                : x (x_)
                , y (y_)
@@ -54,26 +68,65 @@ public:
        T width;
        T height;
 
-       Position<T> position () const {
+       Position<T> position () const
+       {
                return Position<T> (x, y);
        }
 
-       Rect<T> intersection (Rect<T> const & other) const {
-               T const tx = max (x, other.x);
-               T const ty = max (y, other.y);
-       
-               return Rect (
+       boost::optional<Rect<T>> intersection (Rect<T> const & other) const
+       {
+               /* This isn't exactly the paragon of mathematical precision */
+
+               T const tx = std::max (x, other.x);
+               T const ty = std::max (y, other.y);
+
+               Rect r (
                        tx, ty,
-                       min (x + width, other.x + other.width) - tx,
-                       min (y + height, other.y + other.height) - ty
+                       std::min (x + width, other.x + other.width) - tx,
+                       std::min (y + height, other.y + other.height) - ty
                        );
+
+               if (r.width < 0 || r.height < 0) {
+                       return {};
+               }
+
+               return r;
+       }
+
+       void extend (Rect<T> const & other)
+       {
+               T old_x = x;
+               T old_y = y;
+               x = std::min (x, other.x);
+               y = std::min (y, other.y);
+               width = std::max (old_x + width, other.x + other.width) - x;
+               height = std::max (old_y + height, other.y + other.height) - y;
+       }
+
+       Rect<T> extended (T amount) const {
+               Rect<T> c = *this;
+               c.x -= amount;
+               c.y -= amount;
+               c.width += amount * 2;
+               c.height += amount * 2;
+               return c;
        }
 
-       bool contains (Position<T> p) const {
+       bool contains (Position<T> p) const
+       {
                return (p.x >= x && p.x <= (x + width) && p.y >= y && p.y <= (y + height));
        }
 };
 
+
+template <class T>
+bool operator== (Rect<T> const& a, Rect<T> const& b)
+{
+       return a.x == b.x && a.y == b.y && a.width == b.width && a.height == b.height;
+}
+
+
 }
 
+
 #endif