rect.h

// Copyright (C) 2002-2012 Nikolaus Gebhardt
// This file is part of the "Irrlicht Engine".
// For conditions of distribution and use, see copyright notice in irrlicht.h
 
#ifndef __IRR_RECT_H_INCLUDED__
#define __IRR_RECT_H_INCLUDED__
 
#include "irrTypes.h"
#include "dimension2d.h"
#include "position2d.h"
 
namespace irr
{
namespace core
{


    template <class T>
    class rect
    {
    public:

        rect() : UpperLeftCorner(0,0), LowerRightCorner(0,0) {}

        rect(T x, T y, T x2, T y2)
            : UpperLeftCorner(x,y), LowerRightCorner(x2,y2) {}

        rect(const position2d<T>& upperLeft, const position2d<T>& lowerRight)
            : UpperLeftCorner(upperLeft), LowerRightCorner(lowerRight) {}

        template <class U>
        rect(const position2d<T>& pos, const dimension2d<U>& size)
            : UpperLeftCorner(pos), LowerRightCorner(pos.X + size.Width, pos.Y + size.Height) {}

        rect<T> operator+(const position2d<T>& pos) const
        {
            rect<T> ret(*this);
            return ret+=pos;
        }

        rect<T>& operator+=(const position2d<T>& pos)
        {
            UpperLeftCorner += pos;
            LowerRightCorner += pos;
            return *this;
        }

        rect<T> operator-(const position2d<T>& pos) const
        {
            rect<T> ret(*this);
            return ret-=pos;
        }

        rect<T>& operator-=(const position2d<T>& pos)
        {
            UpperLeftCorner -= pos;
            LowerRightCorner -= pos;
            return *this;
        }

        bool operator==(const rect<T>& other) const
        {
            return (UpperLeftCorner == other.UpperLeftCorner &&
                LowerRightCorner == other.LowerRightCorner);
        }

        bool operator!=(const rect<T>& other) const
        {
            return (UpperLeftCorner != other.UpperLeftCorner ||
                LowerRightCorner != other.LowerRightCorner);
        }

        bool operator<(const rect<T>& other) const
        {
            return getArea() < other.getArea();
        }

        T getArea() const
        {
            return getWidth() * getHeight();
        }


        bool isPointInside(const position2d<T>& pos) const
        {
            return (UpperLeftCorner.X <= pos.X &&
                UpperLeftCorner.Y <= pos.Y &&
                LowerRightCorner.X >= pos.X &&
                LowerRightCorner.Y >= pos.Y);
        }


        bool isRectCollided(const rect<T>& other) const
        {
            return (LowerRightCorner.Y > other.UpperLeftCorner.Y &&
                UpperLeftCorner.Y < other.LowerRightCorner.Y &&
                LowerRightCorner.X > other.UpperLeftCorner.X &&
                UpperLeftCorner.X < other.LowerRightCorner.X);
        }


        void clipAgainst(const rect<T>& other)
        {
            if (other.LowerRightCorner.X < LowerRightCorner.X)
                LowerRightCorner.X = other.LowerRightCorner.X;
            if (other.LowerRightCorner.Y < LowerRightCorner.Y)
                LowerRightCorner.Y = other.LowerRightCorner.Y;
 
            if (other.UpperLeftCorner.X > UpperLeftCorner.X)
                UpperLeftCorner.X = other.UpperLeftCorner.X;
            if (other.UpperLeftCorner.Y > UpperLeftCorner.Y)
                UpperLeftCorner.Y = other.UpperLeftCorner.Y;
 
            // correct possible invalid rect resulting from clipping
            if (UpperLeftCorner.Y > LowerRightCorner.Y)
                UpperLeftCorner.Y = LowerRightCorner.Y;
            if (UpperLeftCorner.X > LowerRightCorner.X)
                UpperLeftCorner.X = LowerRightCorner.X;
        }


        bool constrainTo(const rect<T>& other)
        {
            if (other.getWidth() < getWidth() || other.getHeight() < getHeight())
                return false;
 
            T diff = other.LowerRightCorner.X - LowerRightCorner.X;
            if (diff < 0)
            {
                LowerRightCorner.X += diff;
                UpperLeftCorner.X  += diff;
            }
 
            diff = other.LowerRightCorner.Y - LowerRightCorner.Y;
            if (diff < 0)
            {
                LowerRightCorner.Y += diff;
                UpperLeftCorner.Y  += diff;
            }
 
            diff = UpperLeftCorner.X - other.UpperLeftCorner.X;
            if (diff < 0)
            {
                UpperLeftCorner.X  -= diff;
                LowerRightCorner.X -= diff;
            }
 
            diff = UpperLeftCorner.Y - other.UpperLeftCorner.Y;
            if (diff < 0)
            {
                UpperLeftCorner.Y  -= diff;
                LowerRightCorner.Y -= diff;
            }
 
            return true;
        }

        T getWidth() const
        {
            return LowerRightCorner.X - UpperLeftCorner.X;
        }

        T getHeight() const
        {
            return LowerRightCorner.Y - UpperLeftCorner.Y;
        }

        void repair()
        {
            if (LowerRightCorner.X < UpperLeftCorner.X)
            {
                T t = LowerRightCorner.X;
                LowerRightCorner.X = UpperLeftCorner.X;
                UpperLeftCorner.X = t;
            }
 
            if (LowerRightCorner.Y < UpperLeftCorner.Y)
            {
                T t = LowerRightCorner.Y;
                LowerRightCorner.Y = UpperLeftCorner.Y;
                UpperLeftCorner.Y = t;
            }
        }


        bool isValid() const
        {
            return ((LowerRightCorner.X >= UpperLeftCorner.X) &&
                (LowerRightCorner.Y >= UpperLeftCorner.Y));
        }

        position2d<T> getCenter() const
        {
            return position2d<T>(
                    (UpperLeftCorner.X + LowerRightCorner.X) / 2,
                    (UpperLeftCorner.Y + LowerRightCorner.Y) / 2);
        }

        dimension2d<T> getSize() const
        {
            return dimension2d<T>(getWidth(), getHeight());
        }
 


        void addInternalPoint(const position2d<T>& p)
        {
            addInternalPoint(p.X, p.Y);
        }


        void addInternalPoint(T x, T y)
        {
            if (x>LowerRightCorner.X)
                LowerRightCorner.X = x;
            if (y>LowerRightCorner.Y)
                LowerRightCorner.Y = y;
 
            if (x<UpperLeftCorner.X)
                UpperLeftCorner.X = x;
            if (y<UpperLeftCorner.Y)
                UpperLeftCorner.Y = y;
        }

        position2d<T> UpperLeftCorner;
        position2d<T> LowerRightCorner;
    };

    typedef rect<f32> rectf;
    typedef rect<s32> recti;
 
} // end namespace core
} // end namespace irr
 
#endif