new classes; yajl library

[chaz/yoink] / src / rectangle.hh

diff --git a/src/rectangle.hh b/src/rectangle.hh
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+
+/*******************************************************************************
+
+ Copyright (c) 2009, Charles McGarvey
+ All rights reserved.
+ 
+ Redistribution   and   use  in  source  and  binary  forms,  with  or  without
+ modification, are permitted provided that the following conditions are met:
+ 
+   * Redistributions  of  source  code  must retain the above copyright notice,
+     this list of conditions and the following disclaimer.
+   * Redistributions  in binary form must reproduce the above copyright notice,
+     this  list of conditions and the following disclaimer in the documentation
+     and/or other materials provided with the distribution.
+ 
+ THIS  SOFTWARE  IS  PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ AND  ANY  EXPRESS  OR  IMPLIED  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ DISCLAIMED.  IN  NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ FOR  ANY  DIRECT,  INDIRECT,  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ DAMAGES  (INCLUDING,  BUT  NOT  LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ SERVICES;  LOSS  OF  USE,  DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ CAUSED  AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ OR  TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+*******************************************************************************/
+
+#ifndef _RECTANGLE_HH_
+#define _RECTANGLE_HH_
+
+#include "math.hh"
+#include "vector.hh"
+
+
+namespace dc {
+
+//
+// A rectangle is a 2d shape defined by point (origin) and size (width & height)
+// vectors.  The usual rectangle maths are available.  Valid rectangles have
+// positive width and height.  Invalid rectangles will be returned for invalid
+// operations such as trying to get the intersection of two rectangles which
+// don't intersect.  Using an invalid rectangle is undefined, but it may be used
+// after "fixing" it using the fix method which will cause the size to be
+// positive and adjust the origin to be the bottom-left point.  Check the
+// validity of a rectangle using the isValid method especially if the rectangle
+// is a result of an operation which could fail.
+//
+
+class rectangle
+{
+public:
+       // Constructors.
+       rectangle() {}
+       rectangle(point o, point s) {
+               origin = o;
+               size = s;
+       }
+
+       // Rectangle validity.
+       bool isValid() const { return size.x >= 0.0 && size.y >= 0.0; }
+       void fix()
+       {
+               if (size.x <= 0.0)
+               {
+                       size.x = 0.0 - size.x;
+                       origin.x -= size.x;
+               }
+               if (size.y <= 0.0)
+               {
+                       size.y = 0.0 - size.y;
+                       origin.y -= size.y;
+               }
+       }
+
+       // Rectangle operations.
+       scalar area() const { return size.x * size.y; }
+       scalar perimeter() const {
+               return  size.x + size.x + size.y + size.y;
+       }
+
+       bool containsPoint(point pt) const
+       {
+               return origin.x <= pt.x && origin.y <= pt.y &&
+                          pt.x <= origin.x + size.x && pt.y <= origin.y + size.y;
+       }
+
+       void inset(scalar h, scalar v)
+       {
+               origin.x        += h;
+               origin.y        += v;
+               size.x          -= h + h;
+               size.y          -= v + v;
+       }
+       void offset(scalar h, scalar v)
+       {
+               origin.x        -= h;
+               origin.y        -= v;
+               size.x          += h + h;
+               size.y          += v + v;
+       }
+
+       bool containsRect(const rectangle& r) const;
+       bool intersectsRect(const rectangle& r) const;
+       rectangle unionWith(const rectangle& r) const;
+       rectangle intersectionWith(const rectangle& r) const;
+
+       // Checking equality.
+       bool operator == (const rectangle& r) const {
+               return origin == r.origin && size == r.size;
+       }
+       bool operator != (const rectangle& r) const {
+               return !(*this == r);
+       }
+
+       // Data.
+       point origin, size;
+};
+
+} // namespace dc
+
+
+#endif // _RECTANGLE_HH_
+