--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/OrthancStone/Sources/Toolbox/Extent2D.cpp	Tue Jul 07 16:21:02 2020 +0200
@@ -0,0 +1,139 @@
+/**
+ * Stone of Orthanc
+ * Copyright (C) 2012-2016 Sebastien Jodogne, Medical Physics
+ * Department, University Hospital of Liege, Belgium
+ * Copyright (C) 2017-2020 Osimis S.A., Belgium
+ *
+ * This program is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU Affero General Public License
+ * as published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * This program 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
+ * Affero General Public License for more details.
+ * 
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ **/
+
+
+#include "Extent2D.h"
+
+#include <algorithm>
+#include <cassert>
+#include <limits>
+
+namespace OrthancStone
+{
+  Extent2D::Extent2D(double x1,
+                     double y1,
+                     double x2,
+                     double y2) :
+    empty_(false),
+    x1_(x1),
+    y1_(y1),
+    x2_(x2),
+    y2_(y2)
+  {
+    if (x1_ > x2_)
+    {
+      std::swap(x1_, x2_);
+    }
+
+    if (y1_ > y2_)
+    {
+      std::swap(y1_, y2_);
+    }
+  }
+
+
+  void Extent2D::Reset()
+  {
+    empty_ = true;
+    x1_ = 0;
+    y1_ = 0;
+    x2_ = 0;
+    y2_ = 0;      
+  }
+
+  void Extent2D::AddPoint(double x,
+                          double y)
+  {
+    if (empty_)
+    {
+      x1_ = x;
+      y1_ = y;
+      x2_ = x;
+      y2_ = y;
+      empty_ = false;
+    }
+    else
+    {
+      x1_ = std::min(x1_, x);
+      y1_ = std::min(y1_, y);
+      x2_ = std::max(x2_, x);
+      y2_ = std::max(y2_, y);
+    }
+
+    assert(x1_ <= x2_ &&
+           y1_ <= y2_);    // This is the invariant of the structure
+  }
+
+
+  void Extent2D::Union(const Extent2D& other)
+  {
+    if (other.empty_)
+    {
+      return;
+    }
+
+    if (empty_)
+    {
+      *this = other;
+      return;
+    }
+
+    assert(!empty_);
+
+    x1_ = std::min(x1_, other.x1_);
+    y1_ = std::min(y1_, other.y1_);
+    x2_ = std::max(x2_, other.x2_);
+    y2_ = std::max(y2_, other.y2_);
+
+    assert(x1_ <= x2_ &&
+           y1_ <= y2_);    // This is the invariant of the structure
+  }
+
+
+  bool Extent2D::IsEmpty() const
+  {
+    if (empty_)
+    {
+      return true;
+    }
+    else
+    {
+      assert(x1_ <= x2_ &&
+             y1_ <= y2_);
+      return (x2_ <= x1_ + 10 * std::numeric_limits<double>::epsilon() ||
+              y2_ <= y1_ + 10 * std::numeric_limits<double>::epsilon());
+    }
+  }
+
+
+  bool Extent2D::Contains(double x,
+                          double y) const
+  {
+    if (empty_)
+    {
+      return false;
+    }
+    else
+    {
+      return (x >= x1_ && x <= x2_ &&
+              y >= y1_ && y <= y2_);
+    }
+  }
+}