vcglib/vcg/space/box2.h

369 lines
10 KiB
C++

/****************************************************************************
* VCGLib o o *
* Visual and Computer Graphics Library o o *
* _ O _ *
* Copyright(C) 2004 \/)\/ *
* Visual Computing Lab /\/| *
* ISTI - Italian National Research Council | *
* \ *
* All rights reserved. *
* *
* This program 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, *
* but WITHOUT ANY WARRANTY; without even the implied warranty of *
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
* GNU General Public License (http://www.gnu.org/licenses/gpl.txt) *
* for more details. *
* *
****************************************************************************/
#ifndef __VCGLIB_BOX2
#define __VCGLIB_BOX2
#include <assert.h>
#include <algorithm>
#include <vcg/math/base.h>
#include <vcg/space/point2.h>
namespace vcg {
// needed prototype;
template <class SegScalarType> class Segment2;
/** \addtogroup space */
/*@{*/
/**
Templated class for a 2D bounding box. It is stored just as two Point2
@param BoxScalarType (Template Parameter) Specifies the scalar field.
*/
template <class BoxScalarType>
class Box2
{
public:
/// The scalar type
typedef BoxScalarType ScalarType;
typedef Point2<BoxScalarType> PointType ;
/// min coordinate point
PointType min;
/// max coordinate point
PointType max;
/// Standard constructor
inline Box2() { min.X()= 1; max.X()= -1; min.Y()= 1; max.Y()= -1; }
/// Copy constructor
inline Box2( const Box2 & b ) { min=b.min; max=b.max; }
/// Min Max constructor
inline Box2( const Point2<BoxScalarType> & mi, const Point2<BoxScalarType> & ma ) { min = mi; max = ma; }
/// Distructor
inline ~Box2() { }
/// Operator to compare two bounding box
inline bool operator == ( Box2 const & p ) const
{
return min==p.min && max==p.max;
}
/// Initializing the bounding box with a point
void Set( const PointType & p )
{
min = max = p;
}
Point2<BoxScalarType> P(const int & i) const
{
return Point2<BoxScalarType>(
min[0]+ (i%2) * DimX(),
min[1]+ ((i / 2)%2) * DimY());
}
// Initializing with the values
inline void Set( ScalarType minx, ScalarType miny, ScalarType maxx, ScalarType maxy )
{
min[0] = minx;
min[1] = miny;
max[0] = maxx;
max[1] = maxy;
}
/// Set the bounding box to a null value
void SetNull()
{
min.X()= 1; max.X()= -1; min.Y()= 1; max.Y()= -1;
}
/** Function to add two bounding box
the bounding box expand to include the other bounding box (if necessary)
@param b The bounding box to be added
*/
void Add( Box2 const & b )
{
if(IsNull())
{
min=b.min;
max=b.max;
}
else
{
if(min.X() > b.min.X()) min.X() = b.min.X();
if(min.Y() > b.min.Y()) min.Y() = b.min.Y();
if(max.X() < b.max.X()) max.X() = b.max.X();
if(max.Y() < b.max.Y()) max.Y() = b.max.Y();
}
}
/** Adds a point to the bouning box.
the bounding box expand to include the new point (if necessary)
@param p The point 2D
*/
void Add( const PointType & p )
{
if(IsNull()) Set(p);
else
{
if(min.X() > p.X()) min.X() = p.X();
if(min.Y() > p.Y()) min.Y() = p.Y();
if(max.X() < p.X()) max.X() = p.X();
if(max.Y() < p.Y()) max.Y() = p.Y();
}
}
/** Varies the dimension of the bounding box.
@param delta The size delta (if positive, box is enlarged)
*/
void Offset(const ScalarType s)
{
Offset(PointType(s, s));
}
/** Varies the dimension of the bounding box.
@param delta The size delta per dimension (if positive, box is enlarged)
*/
void Offset(const PointType & delta)
{
min -= delta;
max += delta;
}
/** Computes intersection between this and another bounding box
@param b The other bounding box
*/
void Intersect( const Box2 & b )
{
if(min.X() < b.min.X()) min.X() = b.min.X();
if(min.Y() < b.min.Y()) min.Y() = b.min.Y();
if(max.X() > b.max.X()) max.X() = b.max.X();
if(max.Y() > b.max.Y()) max.Y() = b.max.Y();
if(min.X()>max.X() || min.Y()>max.Y()) SetNull();
}
/** Traslate the bounding box by a vectore
@param p The transolation vector
*/
void Translate( const PointType & p )
{
min += p;
max += p;
}
/** Checks whether a 2D point p is inside the box
@param p The point 2D
@return True iff p inside
*/
bool IsIn( PointType const & p ) const
{
return (
min.X() <= p.X() && p.X() <= max.X() &&
min.Y() <= p.Y() && p.Y() <= max.Y()
);
}
/** Checks whether a 2D point p is inside the box, closed at min but open at max
@param p The point in 2D
@return True iff p inside
*/
bool IsInEx( PointType const & p ) const
{
return (
min.X() <= p.X() && p.X() < max.X() &&
min.Y() <= p.Y() && p.Y() < max.Y()
);
}
/** Check bbox collision.
Note: just adjiacent bbox won't collide
@param b A bounding box
@return True iff collision
*/
bool Collide( Box2 const &b )
{
Box2 bb=*this;
bb.Intersect(b);
return bb.IsValid();
}
/** Check if emptry.
@return True iff empty
*/
inline bool IsNull() const { return min.X()>max.X() || min.Y()>max.Y(); }
/** Check consistency.
@return True iff consistent
*/
inline bool IsValid() const { return min.X()<max.X() && min.Y()<max.Y(); }
/** Check if emptry.
@return True iff empty
*/
inline bool IsEmpty() const { return min==max; }
/// Computes length of diagonal
ScalarType Diag() const
{
return Distance(min,max);
}
/// Computes box center
PointType Center() const
{
return (min+max)/2;
}
/// Computes area
inline ScalarType Area() const
{
return (max[0]-min[0])*(max[1]-min[1]);
}
/// computes dimension on X axis.
inline ScalarType DimX() const { return max.X()-min.X(); }
/// computes dimension on Y axis.
inline ScalarType DimY() const { return max.Y()-min.Y(); }
/// Computes sizes (as a vector)
inline PointType Dim() const { return max-min; }
/// Deprecated: use GlobalToLocal
inline void Normalize( PointType & p )
{
p -= min;
p[0] /= max[0]-min[0];
p[1] /= max[1]-min[1];
}
/// Returns global coords of a local point expressed in [0..1]^2
PointType LocalToGlobal(PointType const & p) const{
return PointType(
min[0] + p[0]*(max[0]-min[0]),
min[1] + p[1]*(max[1]-min[1]));
}
/// Returns local coords expressed in [0..1]^2 of a point in R^2
PointType GlobalToLocal(PointType const & p) const{
return PointType(
(p[0]-min[0])/(max[0]-min[0]),
(p[1]-min[1])/(max[1]-min[1])
);
}
/// Turns the bounding box into a square (conservatively)
void MakeSquare(){
ScalarType radius = max( DimX(), DimY() ) / 2;
PointType c = Center();
max = c + PointType(radius, radius);
min = c - PointType(radius, radius);
}
}; // end class definition
template <class ScalarType>
ScalarType DistancePoint2Box2(const Point2<ScalarType> &test,
const Box2<ScalarType> &bbox)
{
///test possible position respect to bounding box
if (!bbox.IsIn(test)){
if ((test.X()<=bbox.min.X())&&(test.Y()<=bbox.min.Y()))
return ((test-bbox.min).Norm());
else
if ((test.X()>=bbox.min.X())&&
(test.X()<=bbox.max.X())&&
(test.Y()<=bbox.min.Y()))
return (bbox.min.Y()-test.Y());
else
if ((test.X()>=bbox.max.X())&&
(test.Y()<=bbox.min.Y()))
return ((test-vcg::Point2<ScalarType>(bbox.max.X(),bbox.min.Y())).Norm());
else
if ((test.Y()>=bbox.min.Y())&&
(test.Y()<=bbox.max.Y())&&
(test.X()>=bbox.max.X()))
return (test.X()-bbox.max.X());
else
if ((test.X()>=bbox.max.X())&&(test.Y()>=bbox.max.Y()))
return ((test-bbox.max).Norm());
else
if ((test.X()>=bbox.min.X())&&
(test.X()<=bbox.max.X())&&
(test.Y()>=bbox.max.Y()))
return (test.Y()-bbox.max.Y());
else
if ((test.X()<=bbox.min.X())&&
(test.Y()>=bbox.max.Y()))
return ((test-vcg::Point2<ScalarType>(bbox.min.X(),bbox.max.Y())).Norm());
else
if ((test.X()<=bbox.min.X())&&
(test.Y()<=bbox.max.Y())&&
(test.Y()>=bbox.min.Y()))
return (bbox.min.X()-test.X());
}
else
{
//return minimum distance
ScalarType dx=std::min<ScalarType>(fabs(test.X()-bbox.min.X()),fabs(bbox.max.X()-test.X()));
ScalarType dy=std::min<ScalarType>(fabs(test.Y()-bbox.min.Y()),fabs(bbox.max.Y()-test.Y()));
return(std::min<ScalarType>(dx,dy));
}
}
template <class ScalarType>
Point2<ScalarType> ClosestPoint2Box2(const Point2<ScalarType> &test,
const Box2<ScalarType> &bbox)
{
Segment2<ScalarType> Segs[4];
Segs[0].P0() = bbox.min;
Segs[0].P1() = vcg::Point2<ScalarType>(bbox.max.X(), bbox.min.Y());
Segs[1].P0() = Segs[0].P1();
Segs[1].P1() = bbox.max;
Segs[2].P0() = Segs[1].P1();
Segs[2].P1() = vcg::Point2<ScalarType>(bbox.min.X(), bbox.max.Y());
Segs[3].P0() = Segs[2].P1();
Segs[3].P1() = bbox.min;
Point2<ScalarType> closest = ClosestPoint(Segs[0], test);
ScalarType minDist = (closest-test).Norm();
for (int i = 1; i < 4; i++)
{
Point2<ScalarType> point = ClosestPoint(Segs[i], test);
ScalarType dist = (test - point).Norm();
if (dist < minDist)
{
minDist = dist;
closest = point;
}
}
return closest;
}
/// Specificazione di box of short
typedef Box2<short> Box2s;
/// Specificazione di box of int
typedef Box2<int> Box2i;
/// Specificazione di box of float
typedef Box2<float> Box2f;
/// Specificazione di box of double
typedef Box2<double> Box2d;
/*@}*/
} // end namespace
#endif