OpenSceneGraph/include/osg/BoundingBox
2005-04-14 21:41:28 +00:00

195 lines
6.9 KiB
C++

/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2005 Robert Osfield
*
* This library is open source and may be redistributed and/or modified under
* the terms of the OpenSceneGraph Public License (OSGPL) version 0.0 or
* (at your option) any later version. The full license is in LICENSE file
* included with this distribution, and on the openscenegraph.org website.
*
* This library 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
* OpenSceneGraph Public License for more details.
*/
#ifndef OSG_BOUNDINGBOX
#define OSG_BOUNDINGBOX 1
#include <osg/Export>
#include <osg/Vec3>
#include <float.h>
namespace osg {
class BoundingSphere;
/** General purpose axis-aligned bounding box class for enclosing objects/vertices.
* Bounds leaf objects in a scene such as osg::Drawable objects. Used for frustum
* culling etc.
*/
class OSG_EXPORT BoundingBox
{
public:
/** Minimum extent. (Smallest X, Y, and Z values of all coordinates.) */
Vec3 _min;
/** Maximum extent. (Greatest X, Y, and Z values of all coordinates.) */
Vec3 _max;
/** Creates an uninitialized bounding box. */
inline BoundingBox() : _min(FLT_MAX,FLT_MAX,FLT_MAX),
_max(-FLT_MAX,-FLT_MAX,-FLT_MAX) {}
/** Creates a bounding box initialized to the given extents. */
inline BoundingBox(float xmin,float ymin,float zmin,
float xmax,float ymax,float zmax) :
_min(xmin,ymin,zmin),
_max(xmax,ymax,zmax) {}
/** Creates a bounding box initialized to the given extents. */
inline BoundingBox(const Vec3& min,const Vec3& max) :
_min(min),
_max(max) {}
/** Clear the bounding box. Erases existing minimum and maximum extents. */
inline void init()
{
_min.set(FLT_MAX,FLT_MAX,FLT_MAX);
_max.set(-FLT_MAX,-FLT_MAX,-FLT_MAX);
}
/** Returns true if the bounding box extents are valid, false otherwise. */
inline bool valid() const
{
return _max.x()>=_min.x() && _max.y()>=_min.y() && _max.z()>=_min.z();
}
/** Sets the bounding box extents. */
inline void set (float xmin,float ymin,float zmin,
float xmax,float ymax,float zmax)
{
_min.set(xmin,ymin,zmin);
_max.set(xmax,ymax,zmax);
}
/** Sets the bounding box extents. */
inline void set(const Vec3& min,const Vec3& max)
{
_min = min;
_max = max;
}
inline float& xMin() { return _min.x(); }
inline float xMin() const { return _min.x(); }
inline float& yMin() { return _min.y(); }
inline float yMin() const { return _min.y(); }
inline float& zMin() { return _min.z(); }
inline float zMin() const { return _min.z(); }
inline float& xMax() { return _max.x(); }
inline float xMax() const { return _max.x(); }
inline float& yMax() { return _max.y(); }
inline float yMax() const { return _max.y(); }
inline float& zMax() { return _max.z(); }
inline float zMax() const { return _max.z(); }
/** Calculates and returns the bounding box center. */
inline const Vec3 center() const
{
return (_min+_max)*0.5f;
}
/** Calculates and returns the bounding box radius. */
inline float radius() const
{
return sqrtf(radius2());
}
/** Calculates and returns the squared length of the bounding box radius.
* Note, radius2() is faster to calculate than radius(). */
inline float radius2() const
{
return 0.25f*((_max-_min).length2());
}
/** Returns a specific corner of the bounding box.
* pos specifies the corner as a number between 0 and 7.
* Each bit selects an axis, X, Y, or Z from least- to
* most-significant. Unset bits select the minimum value
* for that axis, and set bits select the maximum. */
inline const Vec3 corner(unsigned int pos) const
{
return Vec3(pos&1?_max.x():_min.x(),pos&2?_max.y():_min.y(),pos&4?_max.z():_min.z());
}
/** Expands the bounding box to include the given coordinate.
* If the box is uninitialized, set its min and max extents to v. */
inline void expandBy(const Vec3& v)
{
if(v.x()<_min.x()) _min.x() = v.x();
if(v.x()>_max.x()) _max.x() = v.x();
if(v.y()<_min.y()) _min.y() = v.y();
if(v.y()>_max.y()) _max.y() = v.y();
if(v.z()<_min.z()) _min.z() = v.z();
if(v.z()>_max.z()) _max.z() = v.z();
}
/** Expands the bounding box to include the given coordinate.
* If the box is uninitialized, set its min and max extents to
* Vec3(x,y,z). */
inline void expandBy(float x,float y,float z)
{
if(x<_min.x()) _min.x() = x;
if(x>_max.x()) _max.x() = x;
if(y<_min.y()) _min.y() = y;
if(y>_max.y()) _max.y() = y;
if(z<_min.z()) _min.z() = z;
if(z>_max.z()) _max.z() = z;
}
/** Expands this bounding box to include the given bounding box.
* If this box is uninitialized, set it equal to bb. */
void expandBy(const BoundingBox& bb);
/** Expands this bounding box to include the given sphere.
* If this box is uninitialized, set it to include sh. */
void expandBy(const BoundingSphere& sh);
/** Returns the intesection of this bounding box and the specified bounding box. */
BoundingBox intersect(const BoundingBox& bb) const
{ return osg::BoundingBox(osg::maximum(xMin(),bb.xMin()),osg::maximum(yMin(),bb.yMin()),osg::maximum(zMin(),bb.zMin()),
osg::minimum(xMax(),bb.xMax()),osg::minimum(yMax(),bb.yMax()),osg::minimum(zMax(),bb.zMax()));
}
/** Return true if this bounding box intersects the specified bounding box. */
bool intersects(const BoundingBox& bb) const
{ return osg::maximum(xMin(),bb.xMin()) <= osg::minimum(xMax(),bb.xMax()) &&
osg::maximum(yMin(),bb.yMin()) <= osg::minimum(yMax(),bb.yMax()) &&
osg::maximum(zMin(),bb.zMin()) <= osg::minimum(zMax(),bb.zMax());
}
/** Returns true if this bounding box contains the specified coordinate. */
inline bool contains(const Vec3& v) const
{
return valid() &&
(v.x()>=_min.x() && v.x()<=_max.x()) &&
(v.y()>=_min.y() && v.y()<=_max.y()) &&
(v.z()>=_min.z() && v.z()<=_max.z());
}
};
}
#endif