/****************************************************************************
** $Id:  qt/qrect.cpp   3.0.3   edited Oct 12 12:18 $
**
** Implementation of QRect class
**
** Created : 931028
**
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#define	 QRECT_C
#include "qrect.h"
#include "qdatastream.h"

/*!
  \class QRect qrect.h
  \brief The QRect class defines a rectangle in the plane.

  \ingroup images
  \ingroup graphics
  \mainclass

  A rectangle is internally represented as an upper-left corner and a
  bottom-right corner, but it is normally expressed as an upper-left
  corner and a size.

  The coordinate type is QCOORD (defined in qwindowdefs.h as \c int).
  The minimum value of QCOORD is QCOORD_MIN (-2147483648) and the maximum
  value is  QCOORD_MAX (2147483647).

  Note that the size (width and height) of a rectangle might be
  different from what you are used to. If the top-left corner and the
  bottom-right corner are the same, the height and the width of
  the rectangle will both be 1.

  Generally, \e{width = right - left + 1} and \e{height = bottom
  - top + 1}. We designed it this way to make it correspond to
  rectangular spaces used by drawing functions in which the width and
  height denote a number of pixels. For example, drawing a rectangle
  with width and height 1 draws a single pixel.

  The default coordinate system has origin (0, 0) in the top-left
  corner. The positive direction of the y axis is down, and the
  positive x axis is from left to right.

  A QRect can be constructed with a set of left, top, width and height
  integers, from two QPoints or from a QPoint and a QSize. After
  creation the dimensions can be changed, e.g. with setLeft(),
  setRight(), setTop() and setBottom(), or by setting sizes, e.g.
  setWidth(), setHeight() and setSize(). The dimensions can also be
  changed with the move functions,
  e.g. moveBy(), moveCenter(), moveBottomRight(), etc. You can also
  add coordinates to a rectangle with addCoords().

    You can test to see if a QRect contains a specific point with
    contains(). You can also test to see if two QRects intersect with
    intersects() (see also intersect()). To get the bounding rectangle
    of two QRects use unite().

  \sa QPoint, QSize
*/


/*****************************************************************************
  QRect member functions
 *****************************************************************************/

/*!
  \fn QRect::QRect()
  Constructs an invalid rectangle.
*/

/*!
  Constructs a rectangle with \a topLeft as the top-left corner and
  \a bottomRight as the bottom-right corner.
*/

QRect::QRect( const QPoint &topLeft, const QPoint &bottomRight )
{
    x1 = (QCOORD)topLeft.x();
    y1 = (QCOORD)topLeft.y();
    x2 = (QCOORD)bottomRight.x();
    y2 = (QCOORD)bottomRight.y();
}

/*!
  Constructs a rectangle with \a topLeft as the top-left corner and
  \a size as the rectangle size.
*/

QRect::QRect( const QPoint &topLeft, const QSize &size )
{
    x1 = (QCOORD)topLeft.x();
    y1 = (QCOORD)topLeft.y();
    x2 = (QCOORD)(x1+size.width()-1);
    y2 = (QCOORD)(y1+size.height()-1);
}

/*!
  \fn QRect::QRect( int left, int top, int width, int height )

  Constructs a rectangle with the \a top, \a left corner and \a
  width and \a height.

  Example (creates three identical rectangles):
  \code
    QRect r1( QPoint(100,200), QPoint(110,215) );
    QRect r2( QPoint(100,200), QSize(11,16) );
    QRect r3( 100, 200, 11, 16 );
  \endcode
*/


/*!
  \fn bool QRect::isNull() const

  Returns TRUE if the rectangle is a null rectangle; otherwise returns FALSE.

  A null rectangle has both the width and the height set to 0, that is
  right() == left() - 1 and bottom() == top() - 1.

  Remember that if right() == left() and bottom() == top(), then the
  rectangle has width 1 and height 1.

  A null rectangle is also empty.

  A null rectangle is not valid.

  \sa isEmpty(), isValid()
*/

/*!
  \fn bool QRect::isEmpty() const

  Returns TRUE if the rectangle is empty; otherwise returns FALSE.

  An empty rectangle has a left() \> right() or top() \> bottom().

  An empty rectangle is not valid. \c{isEmpty() == !isValid()}

  \sa isNull(), isValid()
*/

/*!
  \fn bool QRect::isValid() const

  Returns TRUE if the rectangle is valid or FALSE if it is invalid (empty).

  A valid rectangle has a left() \<= right() and top() \<= bottom().

  \c{isValid() == !isEmpty()}

  \sa isNull(), isEmpty(), normalize()
*/


/*!
  Returns a normalized rectangle, i.e. a rectangle that has a
  non-negative width and height.

  It swaps left and right if left() \> right(), and swaps top and bottom if
  top() \> bottom().

  \sa isValid()
*/

QRect QRect::normalize() const
{
    QRect r;
    if ( x2 < x1 ) {				// swap bad x values
	r.x1 = x2;
	r.x2 = x1;
    } else {
	r.x1 = x1;
	r.x2 = x2;
    }
    if ( y2 < y1 ) {				// swap bad y values
	r.y1 = y2;
	r.y2 = y1;
    } else {
	r.y1 = y1;
	r.y2 = y2;
    }
    return r;
}


/*!
  \fn int QRect::left() const

  Returns the left coordinate of the rectangle. Identical to x().

  \sa x(), top(), right(), setLeft(), topLeft(), bottomLeft()
*/

/*!
  \fn int QRect::top() const

  Returns the top coordinate of the rectangle. Identical to y().

  \sa y(), left(), bottom(), setTop(), topLeft(), topRight()
*/

/*!
  \fn int QRect::right() const

  Returns the right coordinate of the rectangle.

  \sa left(), setRight(), topRight(), bottomRight()
*/

/*!
  \fn int QRect::bottom() const

  Returns the bottom coordinate of the rectangle.

  \sa top(), setBottom(), bottomLeft(), bottomRight()
*/

/*!
  \fn QCOORD &QRect::rLeft()

  Returns a reference to the left coordinate of the rectangle.

  \sa rTop(), rRight(), rBottom()
*/

/*!
  \fn QCOORD &QRect::rTop()

  Returns a reference to the top coordinate of the rectangle.

  \sa rLeft(),  rRight(), rBottom()
*/

/*!
  \fn QCOORD &QRect::rRight()

  Returns a reference to the right coordinate of the rectangle.

  \sa rLeft(), rTop(), rBottom()
*/

/*!
  \fn QCOORD &QRect::rBottom()

  Returns a reference to the bottom coordinate of the rectangle.

  \sa rLeft(), rTop(), rRight()
*/

/*!
  \fn int QRect::x() const

  Returns the left coordinate of the rectangle.	 Identical to left().

  \sa left(), y(), setX()
*/

/*!
  \fn int QRect::y() const

  Returns the top coordinate of the rectangle.	Identical to top().

  \sa top(), x(), setY()
*/

/*!
  \fn void QRect::setLeft( int pos )

  Sets the left edge of the rectangle to \a pos. May change the
  width, but will never change the right edge of the rectangle.

  Identical to setX().

  \sa left(), setTop(), setWidth()
*/

/*!
  \fn void QRect::setTop( int pos )

  Sets the top edge of the rectangle to \a pos. May change the height,
  but will never change the bottom edge of the rectangle.

  Identical to setY().

  \sa top(), setBottom(), setHeight()
*/

/*!
  \fn void QRect::setRight( int pos )

  Sets the right edge of the rectangle to \a pos. May change the width, but
  will never change the left edge of the rectangle.

  \sa right(), setLeft(), setWidth()
*/

/*!
  \fn void QRect::setBottom( int pos )

  Sets the bottom edge of the rectangle to \a pos. May change the height,
  but will never change the top edge of the rectangle.

  \sa bottom(), setTop(), setHeight()
*/

/*!
  \fn void QRect::setX( int x )

  Sets the x position of the rectangle (its left end) to \a x. May change
  the width, but will never change the right edge of the rectangle.

  Identical to setLeft().

  \sa x(), setY()
*/

/*!
  \fn void QRect::setY( int y )

  Sets the y position of the rectangle (its top) to \a y. May change the
  height, but will never change the bottom edge of the rectangle.

  Identical to setTop().

  \sa y(), setX()
*/

/*!
  \fn QPoint QRect::topLeft() const
  Returns the top-left position of the rectangle.
  \sa moveTopLeft(), topRight(), bottomLeft(), bottomRight(), left(), top()
*/

/*!
  \fn QPoint QRect::bottomRight() const
  Returns the bottom-right position of the rectangle.
  \sa moveBottomRight(), bottomLeft(), topLeft(), topRight(), bottom(), right()
*/

/*!
  \fn QPoint QRect::topRight() const
  Returns the top-right position of the rectangle.
  \sa moveTopRight(), topLeft(), bottomLeft(), bottomRight(), top(), right()
*/

/*!
  \fn QPoint QRect::bottomLeft() const
  Returns the bottom-left position of the rectangle.
  \sa moveBottomLeft(), bottomRight(), topLeft(), topRight(), bottom(), left()
*/

/*!
  \fn QPoint QRect::center() const
  Returns the center point of the rectangle.
  \sa moveCenter(), topLeft(), topRight(), bottomLeft(), bottomRight()
*/


/*!
  Extracts the rectangle parameters as the position \a *x, \a *y
  and width \a *w and height \a *h.
  \sa setRect(), coords()
*/

void QRect::rect( int *x, int *y, int *w, int *h ) const
{
    *x = x1;
    *y = y1;
    *w = x2-x1+1;
    *h = y2-y1+1;
}

/*!
  Extracts the rectangle parameters as the top-left point \a *xp1,
  \a *yp1 and the bottom-right point \a *xp2, \a *yp2.
  \sa setCoords(), rect()
*/

void QRect::coords( int *xp1, int *yp1, int *xp2, int *yp2 ) const
{
    *xp1 = x1;
    *yp1 = y1;
    *xp2 = x2;
    *yp2 = y2;
}

/*!
  Sets the top-left position of the rectangle to \a p, leaving the
  size unchanged.
  \sa topLeft(), moveTopRight(), moveBottomLeft(), moveBottomRight(),
  setTop(), setLeft()
*/

void QRect::moveTopLeft( const QPoint &p )
{
    x2 += (QCOORD)(p.x() - x1);
    y2 += (QCOORD)(p.y() - y1);
    x1 = (QCOORD)p.x();
    y1 = (QCOORD)p.y();
}

/*!
  Sets the bottom-right position of the rectangle to \a p, leaving the size
  unchanged.
  \sa bottomRight(), moveBottomLeft(), moveTopLeft(), moveTopRight(),
  setBottom(), setRight()
*/

void QRect::moveBottomRight( const QPoint &p )
{
    x1 += (QCOORD)(p.x() - x2);
    y1 += (QCOORD)(p.y() - y2);
    x2 = (QCOORD)p.x();
    y2 = (QCOORD)p.y();
}

/*!
  Sets the top-right position of the rectangle to \a p, leaving the
  size unchanged.
  \sa topRight(), moveTopLeft(), moveBottomLeft(), moveBottomRight(),
  setTop(), setRight()
*/

void QRect::moveTopRight( const QPoint &p )
{
    x1 += (QCOORD)(p.x() - x2);
    y2 += (QCOORD)(p.y() - y1);
    x2 = (QCOORD)p.x();
    y1 = (QCOORD)p.y();
}

/*!
  Sets the bottom-left position of the rectangle to \a p, leaving
  the size unchanged.
  \sa bottomLeft(), moveBottomRight(), moveTopLeft(), moveTopRight(),
  setBottom(), setLeft()
*/

void QRect::moveBottomLeft( const QPoint &p )
{
    x2 += (QCOORD)(p.x() - x1);
    y1 += (QCOORD)(p.y() - y2);
    x1 = (QCOORD)p.x();
    y2 = (QCOORD)p.y();
}


/*!
  Sets the center point of the rectangle to \a p, leaving the size
  unchanged.
  \sa center(), moveTopLeft(), moveTopRight(), moveBottomLeft(), moveBottomRight()
*/

void QRect::moveCenter( const QPoint &p )
{
    QCOORD w = x2 - x1;
    QCOORD h = y2 - y1;
    x1 = (QCOORD)(p.x() - w/2);
    y1 = (QCOORD)(p.y() - h/2);
    x2 = x1 + w;
    y2 = y1 + h;
}


/*!
  Moves the rectangle \a dx along the X axis and \a dy along the Y
  axis, relative to the current position. (Positive values move the
  rectangle right and/or down.)
*/


void QRect::moveBy( int dx, int dy )
{
    x1 += (QCOORD)dx;
    y1 += (QCOORD)dy;
    x2 += (QCOORD)dx;
    y2 += (QCOORD)dy;
}

/*!
  Sets the coordinates of the rectangle's top-left corner to \a
  (x, y), and its size to \a (w, h).
  \sa rect(), setCoords()
*/

void QRect::setRect( int x, int y, int w, int h )
{
    x1 = (QCOORD)x;
    y1 = (QCOORD)y;
    x2 = (QCOORD)(x+w-1);
    y2 = (QCOORD)(y+h-1);
}

/*!
  Sets the coordinates of the rectangle's top-left corner to \a (xp1, yp1),
  and the coordinates of its bottom-right corner to \a (xp2, yp2).
  \sa coords(), setRect()
*/

void QRect::setCoords( int xp1, int yp1, int xp2, int yp2 )
{
    x1 = (QCOORD)xp1;
    y1 = (QCOORD)yp1;
    x2 = (QCOORD)xp2;
    y2 = (QCOORD)yp2;
}

/*!
  Adds \a xp1, \a yp1, \a xp2 and \a yp2 respectively to the existing
  coordinates of the rectangle.
*/

void QRect::addCoords( int xp1, int yp1, int xp2, int yp2 )
{
    x1 += (QCOORD)xp1;
    y1 += (QCOORD)yp1;
    x2 += (QCOORD)xp2;
    y2 += (QCOORD)yp2;
}

/*!
  \fn QSize QRect::size() const
  Returns the size of the rectangle.
  \sa width(), height()
*/

/*!
  \fn int QRect::width() const
  Returns the width of the rectangle.  The width includes both the
  left and right edges, i.e. width = right - left + 1.
  \sa height(), size(), setHeight()
*/

/*!
  \fn int QRect::height() const
  Returns the height of the rectangle.	The height includes both the
  top and bottom edges, i.e. height = bottom - top + 1.
  \sa width(), size(), setHeight()
*/

/*!
  Sets the width of the rectangle to \a w. The right edge is
  changed, but not the left edge.
  \sa width(), setLeft(), setRight(), setSize()
*/

void QRect::setWidth( int w )
{
    x2 = (QCOORD)(x1 + w - 1);
}

/*!
  Sets the height of the rectangle to \a h. The top edge is not
  moved, but the bottom edge may be moved.
  \sa height(), setTop(), setBottom(), setSize()
*/

void QRect::setHeight( int h )
{
    y2 = (QCOORD)(y1 + h - 1);
}

/*!
  Sets the size of the rectangle to \a s. The top-left corner is not moved.
  \sa size(), setWidth(), setHeight()
*/

void QRect::setSize( const QSize &s )
{
    x2 = (QCOORD)(s.width() +x1-1);
    y2 = (QCOORD)(s.height()+y1-1);
}

/*!
  Returns TRUE if the point \a p is inside or on the edge of the
  rectangle; otherwise returns FALSE.

  If \a proper is TRUE, this function returns TRUE only if \a p is
  inside (not on the edge).
*/

bool QRect::contains( const QPoint &p, bool proper ) const
{
    if ( proper )
	return p.x() > x1 && p.x() < x2 &&
	       p.y() > y1 && p.y() < y2;
    else
	return p.x() >= x1 && p.x() <= x2 &&
	       p.y() >= y1 && p.y() <= y2;
}

/*!
  \overload bool QRect::contains( int x, int y, bool proper ) const
  Returns TRUE if the point \a x, \a y is inside this rectangle;
  otherwise returns FALSE.

  If \a proper is TRUE, this function returns TRUE only if the point
  is entirely inside (not on the edge).
*/

/*!
    \overload
  Returns TRUE if the rectangle \a r is inside this rectangle;
  otherwise returns FALSE.

  If \a proper is TRUE, this function returns TRUE only if \a r is
  entirely inside (not on the edge).

  \sa unite(), intersect(), intersects()
*/

bool QRect::contains( const QRect &r, bool proper ) const
{
    if ( proper )
	return r.x1 > x1 && r.x2 < x2 && r.y1 > y1 && r.y2 < y2;
    else
	return r.x1 >= x1 && r.x2 <= x2 && r.y1 >= y1 && r.y2 <= y2;
}

/*!
  Unites this rectangle with rectangle \a r.
*/
QRect& QRect::operator|=(const QRect &r)
{
    *this = *this | r;
    return *this;
}

/*!
  Intersects this rectangle with rectangle \a r.
*/
QRect& QRect::operator&=(const QRect &r)
{
    *this = *this & r;
    return *this;
}


/*!
  Returns the bounding rectangle of this rectangle and rectangle \a r.

  The bounding rectangle of a nonempty rectangle and an empty or
  invalid rectangle is defined to be the nonempty rectangle.

  \sa operator|=(), operator&(), intersects(), contains()
*/

QRect QRect::operator|(const QRect &r) const
{
    if ( isValid() ) {
	if ( r.isValid() ) {
	    QRect tmp;
	    tmp.setLeft(   QMIN( x1, r.x1 ) );
	    tmp.setRight(  QMAX( x2, r.x2 ) );
	    tmp.setTop(	   QMIN( y1, r.y1 ) );
	    tmp.setBottom( QMAX( y2, r.y2 ) );
	    return tmp;
	} else {
	    return *this;
	}
    } else {
	return r;
    }
}

/*!
  Returns the bounding rectangle of this rectangle and rectangle \a r.
  \c{r.unite(s)} is equivalent to \c{r|s}.
*/
QRect QRect::unite( const QRect &r ) const
{
    return *this | r;
}


/*!
  Returns the intersection of this rectangle and rectangle \a r.

  Returns an empty rectangle if there is no intersection.

  \sa operator&=(), operator|(), isEmpty(), intersects(), contains()
*/

QRect QRect::operator&( const QRect &r ) const
{
    QRect tmp;
    tmp.x1 = QMAX( x1, r.x1 );
    tmp.x2 = QMIN( x2, r.x2 );
    tmp.y1 = QMAX( y1, r.y1 );
    tmp.y2 = QMIN( y2, r.y2 );
    return tmp;
}

/*!
  Returns the intersection of this rectangle and rectangle \a r.
  \c{r.intersect(s)} is equivalent to \c{r&s}.
*/
QRect QRect::intersect( const QRect &r ) const
{
    return *this & r;
}

/*!
  Returns TRUE if this rectangle intersects with rectangle \a r (there
  is at least one pixel that is within both rectangles); otherwise
  returns FALSE.
  \sa intersect(), contains()
*/

bool QRect::intersects( const QRect &r ) const
{
    return ( QMAX( x1, r.x1 ) <= QMIN( x2, r.x2 ) &&
	     QMAX( y1, r.y1 ) <= QMIN( y2, r.y2 ) );
}


/*!
  \relates QRect
  Returns TRUE if \a r1 and \a r2 are equal; otherwise returns FALSE.
*/

bool operator==( const QRect &r1, const QRect &r2 )
{
    return r1.x1==r2.x1 && r1.x2==r2.x2 && r1.y1==r2.y1 && r1.y2==r2.y2;
}

/*!
  \relates QRect
  Returns TRUE if \a r1 and \a r2 are different; otherwise returns FALSE.
*/

bool operator!=( const QRect &r1, const QRect &r2 )
{
    return r1.x1!=r2.x1 || r1.x2!=r2.x2 || r1.y1!=r2.y1 || r1.y2!=r2.y2;
}


/*****************************************************************************
  QRect stream functions
 *****************************************************************************/
#ifndef QT_NO_DATASTREAM
/*!
  \relates QRect

  Writes the QRect, \a r, to the stream \a s, and returns a reference
  to the stream.

  \sa \link datastreamformat.html Format of the QDataStream operators \endlink
*/

QDataStream &operator<<( QDataStream &s, const QRect &r )
{
    if ( s.version() == 1 )
	s << (Q_INT16)r.left() << (Q_INT16)r.top()
	  << (Q_INT16)r.right() << (Q_INT16)r.bottom();
    else
	s << (Q_INT32)r.left() << (Q_INT32)r.top()
	  << (Q_INT32)r.right() << (Q_INT32)r.bottom();
    return s;
}

/*!
  \relates QRect

  Reads a QRect from the stream \a s into rect \a r and returns a
  reference to the stream.

  \sa \link datastreamformat.html Format of the QDataStream operators \endlink
*/

QDataStream &operator>>( QDataStream &s, QRect &r )
{
    if ( s.version() == 1 ) {
	Q_INT16 x1, y1, x2, y2;
	s >> x1; s >> y1; s >> x2; s >> y2;
	r.setCoords( x1, y1, x2, y2 );
    }
    else {
	Q_INT32 x1, y1, x2, y2;
	s >> x1; s >> y1; s >> x2; s >> y2;
	r.setCoords( x1, y1, x2, y2 );
    }
    return s;
}
#endif // QT_NO_DATASTREAM
