1 // This file is part of Eigen, a lightweight C++ template library
2 // for linear algebra.
3 //
4 // Copyright (C) 2008 Gael Guennebaud <[email protected]>
5 //
6 // This Source Code Form is subject to the terms of the Mozilla
7 // Public License v. 2.0. If a copy of the MPL was not distributed
8 // with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
9
10 // Function void Eigen::AlignedBox::transform(const Transform& transform)
11 // is provided under the following license agreement:
12 //
13 // Software License Agreement (BSD License)
14 //
15 // Copyright (c) 2011-2014, Willow Garage, Inc.
16 // Copyright (c) 2014-2015, Open Source Robotics Foundation
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45
46 #ifndef EIGEN_ALIGNEDBOX_H
47 #define EIGEN_ALIGNEDBOX_H
48
49 namespace Eigen {
50
51 /** \geometry_module \ingroup Geometry_Module
52 *
53 *
54 * \class AlignedBox
55 *
56 * \brief An axis aligned box
57 *
58 * \tparam _Scalar the type of the scalar coefficients
59 * \tparam _AmbientDim the dimension of the ambient space, can be a compile time value or Dynamic.
60 *
61 * This class represents an axis aligned box as a pair of the minimal and maximal corners.
62 * \warning The result of most methods is undefined when applied to an empty box. You can check for empty boxes using isEmpty().
63 * \sa alignedboxtypedefs
64 */
65 template <typename _Scalar, int _AmbientDim>
66 class AlignedBox
67 {
68 public:
69 EIGEN_MAKE_ALIGNED_OPERATOR_NEW_IF_VECTORIZABLE_FIXED_SIZE(_Scalar,_AmbientDim)
70 enum { AmbientDimAtCompileTime = _AmbientDim };
71 typedef _Scalar Scalar;
72 typedef NumTraits<Scalar> ScalarTraits;
73 typedef Eigen::Index Index; ///< \deprecated since Eigen 3.3
74 typedef typename ScalarTraits::Real RealScalar;
75 typedef typename ScalarTraits::NonInteger NonInteger;
76 typedef Matrix<Scalar,AmbientDimAtCompileTime,1> VectorType;
77 typedef CwiseBinaryOp<internal::scalar_sum_op<Scalar>, const VectorType, const VectorType> VectorTypeSum;
78
79 /** Define constants to name the corners of a 1D, 2D or 3D axis aligned bounding box */
80 enum CornerType
81 {
82 /** 1D names @{ */
83 Min=0, Max=1,
84 /** @} */
85
86 /** Identifier for 2D corner @{ */
87 BottomLeft=0, BottomRight=1,
88 TopLeft=2, TopRight=3,
89 /** @} */
90
91 /** Identifier for 3D corner @{ */
92 BottomLeftFloor=0, BottomRightFloor=1,
93 TopLeftFloor=2, TopRightFloor=3,
94 BottomLeftCeil=4, BottomRightCeil=5,
95 TopLeftCeil=6, TopRightCeil=7
96 /** @} */
97 };
98
99
100 /** Default constructor initializing a null box. */
AlignedBox()101 EIGEN_DEVICE_FUNC inline AlignedBox()
102 { if (EIGEN_CONST_CONDITIONAL(AmbientDimAtCompileTime!=Dynamic)) setEmpty(); }
103
104 /** Constructs a null box with \a _dim the dimension of the ambient space. */
AlignedBox(Index _dim)105 EIGEN_DEVICE_FUNC inline explicit AlignedBox(Index _dim) : m_min(_dim), m_max(_dim)
106 { setEmpty(); }
107
108 /** Constructs a box with extremities \a _min and \a _max.
109 * \warning If either component of \a _min is larger than the same component of \a _max, the constructed box is empty. */
110 template<typename OtherVectorType1, typename OtherVectorType2>
AlignedBox(const OtherVectorType1 & _min,const OtherVectorType2 & _max)111 EIGEN_DEVICE_FUNC inline AlignedBox(const OtherVectorType1& _min, const OtherVectorType2& _max) : m_min(_min), m_max(_max) {}
112
113 /** Constructs a box containing a single point \a p. */
114 template<typename Derived>
AlignedBox(const MatrixBase<Derived> & p)115 EIGEN_DEVICE_FUNC inline explicit AlignedBox(const MatrixBase<Derived>& p) : m_min(p), m_max(m_min)
116 { }
117
~AlignedBox()118 EIGEN_DEVICE_FUNC ~AlignedBox() {}
119
120 /** \returns the dimension in which the box holds */
dim()121 EIGEN_DEVICE_FUNC inline Index dim() const { return AmbientDimAtCompileTime==Dynamic ? m_min.size() : Index(AmbientDimAtCompileTime); }
122
123 /** \deprecated use isEmpty() */
isNull()124 EIGEN_DEVICE_FUNC inline bool isNull() const { return isEmpty(); }
125
126 /** \deprecated use setEmpty() */
setNull()127 EIGEN_DEVICE_FUNC inline void setNull() { setEmpty(); }
128
129 /** \returns true if the box is empty.
130 * \sa setEmpty */
isEmpty()131 EIGEN_DEVICE_FUNC inline bool isEmpty() const { return (m_min.array() > m_max.array()).any(); }
132
133 /** Makes \c *this an empty box.
134 * \sa isEmpty */
setEmpty()135 EIGEN_DEVICE_FUNC inline void setEmpty()
136 {
137 m_min.setConstant( ScalarTraits::highest() );
138 m_max.setConstant( ScalarTraits::lowest() );
139 }
140
141 /** \returns the minimal corner */
142 EIGEN_DEVICE_FUNC inline const VectorType& (min)() const { return m_min; }
143 /** \returns a non const reference to the minimal corner */
144 EIGEN_DEVICE_FUNC inline VectorType& (min)() { return m_min; }
145 /** \returns the maximal corner */
146 EIGEN_DEVICE_FUNC inline const VectorType& (max)() const { return m_max; }
147 /** \returns a non const reference to the maximal corner */
148 EIGEN_DEVICE_FUNC inline VectorType& (max)() { return m_max; }
149
150 /** \returns the center of the box */
EIGEN_EXPR_BINARYOP_SCALAR_RETURN_TYPE(VectorTypeSum,RealScalar,quotient)151 EIGEN_DEVICE_FUNC inline const EIGEN_EXPR_BINARYOP_SCALAR_RETURN_TYPE(VectorTypeSum, RealScalar, quotient)
152 center() const
153 { return (m_min+m_max)/RealScalar(2); }
154
155 /** \returns the lengths of the sides of the bounding box.
156 * Note that this function does not get the same
157 * result for integral or floating scalar types: see
158 */
sizes()159 EIGEN_DEVICE_FUNC inline const CwiseBinaryOp< internal::scalar_difference_op<Scalar,Scalar>, const VectorType, const VectorType> sizes() const
160 { return m_max - m_min; }
161
162 /** \returns the volume of the bounding box */
volume()163 EIGEN_DEVICE_FUNC inline Scalar volume() const
164 { return sizes().prod(); }
165
166 /** \returns an expression for the bounding box diagonal vector
167 * if the length of the diagonal is needed: diagonal().norm()
168 * will provide it.
169 */
diagonal()170 EIGEN_DEVICE_FUNC inline CwiseBinaryOp< internal::scalar_difference_op<Scalar,Scalar>, const VectorType, const VectorType> diagonal() const
171 { return sizes(); }
172
173 /** \returns the vertex of the bounding box at the corner defined by
174 * the corner-id corner. It works only for a 1D, 2D or 3D bounding box.
175 * For 1D bounding boxes corners are named by 2 enum constants:
176 * BottomLeft and BottomRight.
177 * For 2D bounding boxes, corners are named by 4 enum constants:
178 * BottomLeft, BottomRight, TopLeft, TopRight.
179 * For 3D bounding boxes, the following names are added:
180 * BottomLeftCeil, BottomRightCeil, TopLeftCeil, TopRightCeil.
181 */
corner(CornerType corner)182 EIGEN_DEVICE_FUNC inline VectorType corner(CornerType corner) const
183 {
184 EIGEN_STATIC_ASSERT(_AmbientDim <= 3, THIS_METHOD_IS_ONLY_FOR_VECTORS_OF_A_SPECIFIC_SIZE);
185
186 VectorType res;
187
188 Index mult = 1;
189 for(Index d=0; d<dim(); ++d)
190 {
191 if( mult & corner ) res[d] = m_max[d];
192 else res[d] = m_min[d];
193 mult *= 2;
194 }
195 return res;
196 }
197
198 /** \returns a random point inside the bounding box sampled with
199 * a uniform distribution */
sample()200 EIGEN_DEVICE_FUNC inline VectorType sample() const
201 {
202 VectorType r(dim());
203 for(Index d=0; d<dim(); ++d)
204 {
205 if(!ScalarTraits::IsInteger)
206 {
207 r[d] = m_min[d] + (m_max[d]-m_min[d])
208 * internal::random<Scalar>(Scalar(0), Scalar(1));
209 }
210 else
211 r[d] = internal::random(m_min[d], m_max[d]);
212 }
213 return r;
214 }
215
216 /** \returns true if the point \a p is inside the box \c *this. */
217 template<typename Derived>
contains(const MatrixBase<Derived> & p)218 EIGEN_DEVICE_FUNC inline bool contains(const MatrixBase<Derived>& p) const
219 {
220 typename internal::nested_eval<Derived,2>::type p_n(p.derived());
221 return (m_min.array()<=p_n.array()).all() && (p_n.array()<=m_max.array()).all();
222 }
223
224 /** \returns true if the box \a b is entirely inside the box \c *this. */
contains(const AlignedBox & b)225 EIGEN_DEVICE_FUNC inline bool contains(const AlignedBox& b) const
226 { return (m_min.array()<=(b.min)().array()).all() && ((b.max)().array()<=m_max.array()).all(); }
227
228 /** \returns true if the box \a b is intersecting the box \c *this.
229 * \sa intersection, clamp */
intersects(const AlignedBox & b)230 EIGEN_DEVICE_FUNC inline bool intersects(const AlignedBox& b) const
231 { return (m_min.array()<=(b.max)().array()).all() && ((b.min)().array()<=m_max.array()).all(); }
232
233 /** Extends \c *this such that it contains the point \a p and returns a reference to \c *this.
234 * \sa extend(const AlignedBox&) */
235 template<typename Derived>
extend(const MatrixBase<Derived> & p)236 EIGEN_DEVICE_FUNC inline AlignedBox& extend(const MatrixBase<Derived>& p)
237 {
238 typename internal::nested_eval<Derived,2>::type p_n(p.derived());
239 m_min = m_min.cwiseMin(p_n);
240 m_max = m_max.cwiseMax(p_n);
241 return *this;
242 }
243
244 /** Extends \c *this such that it contains the box \a b and returns a reference to \c *this.
245 * \sa merged, extend(const MatrixBase&) */
extend(const AlignedBox & b)246 EIGEN_DEVICE_FUNC inline AlignedBox& extend(const AlignedBox& b)
247 {
248 m_min = m_min.cwiseMin(b.m_min);
249 m_max = m_max.cwiseMax(b.m_max);
250 return *this;
251 }
252
253 /** Clamps \c *this by the box \a b and returns a reference to \c *this.
254 * \note If the boxes don't intersect, the resulting box is empty.
255 * \sa intersection(), intersects() */
clamp(const AlignedBox & b)256 EIGEN_DEVICE_FUNC inline AlignedBox& clamp(const AlignedBox& b)
257 {
258 m_min = m_min.cwiseMax(b.m_min);
259 m_max = m_max.cwiseMin(b.m_max);
260 return *this;
261 }
262
263 /** Returns an AlignedBox that is the intersection of \a b and \c *this
264 * \note If the boxes don't intersect, the resulting box is empty.
265 * \sa intersects(), clamp, contains() */
intersection(const AlignedBox & b)266 EIGEN_DEVICE_FUNC inline AlignedBox intersection(const AlignedBox& b) const
267 {return AlignedBox(m_min.cwiseMax(b.m_min), m_max.cwiseMin(b.m_max)); }
268
269 /** Returns an AlignedBox that is the union of \a b and \c *this.
270 * \note Merging with an empty box may result in a box bigger than \c *this.
271 * \sa extend(const AlignedBox&) */
merged(const AlignedBox & b)272 EIGEN_DEVICE_FUNC inline AlignedBox merged(const AlignedBox& b) const
273 { return AlignedBox(m_min.cwiseMin(b.m_min), m_max.cwiseMax(b.m_max)); }
274
275 /** Translate \c *this by the vector \a t and returns a reference to \c *this. */
276 template<typename Derived>
translate(const MatrixBase<Derived> & a_t)277 EIGEN_DEVICE_FUNC inline AlignedBox& translate(const MatrixBase<Derived>& a_t)
278 {
279 const typename internal::nested_eval<Derived,2>::type t(a_t.derived());
280 m_min += t;
281 m_max += t;
282 return *this;
283 }
284
285 /** \returns a copy of \c *this translated by the vector \a t. */
286 template<typename Derived>
translated(const MatrixBase<Derived> & a_t)287 EIGEN_DEVICE_FUNC inline AlignedBox translated(const MatrixBase<Derived>& a_t) const
288 {
289 AlignedBox result(m_min, m_max);
290 result.translate(a_t);
291 return result;
292 }
293
294 /** \returns the squared distance between the point \a p and the box \c *this,
295 * and zero if \a p is inside the box.
296 * \sa exteriorDistance(const MatrixBase&), squaredExteriorDistance(const AlignedBox&)
297 */
298 template<typename Derived>
299 EIGEN_DEVICE_FUNC inline Scalar squaredExteriorDistance(const MatrixBase<Derived>& p) const;
300
301 /** \returns the squared distance between the boxes \a b and \c *this,
302 * and zero if the boxes intersect.
303 * \sa exteriorDistance(const AlignedBox&), squaredExteriorDistance(const MatrixBase&)
304 */
305 EIGEN_DEVICE_FUNC inline Scalar squaredExteriorDistance(const AlignedBox& b) const;
306
307 /** \returns the distance between the point \a p and the box \c *this,
308 * and zero if \a p is inside the box.
309 * \sa squaredExteriorDistance(const MatrixBase&), exteriorDistance(const AlignedBox&)
310 */
311 template<typename Derived>
exteriorDistance(const MatrixBase<Derived> & p)312 EIGEN_DEVICE_FUNC inline NonInteger exteriorDistance(const MatrixBase<Derived>& p) const
313 { EIGEN_USING_STD(sqrt) return sqrt(NonInteger(squaredExteriorDistance(p))); }
314
315 /** \returns the distance between the boxes \a b and \c *this,
316 * and zero if the boxes intersect.
317 * \sa squaredExteriorDistance(const AlignedBox&), exteriorDistance(const MatrixBase&)
318 */
exteriorDistance(const AlignedBox & b)319 EIGEN_DEVICE_FUNC inline NonInteger exteriorDistance(const AlignedBox& b) const
320 { EIGEN_USING_STD(sqrt) return sqrt(NonInteger(squaredExteriorDistance(b))); }
321
322 /**
323 * Specialization of transform for pure translation.
324 */
325 template<int Mode, int Options>
transform(const typename Transform<Scalar,AmbientDimAtCompileTime,Mode,Options>::TranslationType & translation)326 EIGEN_DEVICE_FUNC inline void transform(
327 const typename Transform<Scalar, AmbientDimAtCompileTime, Mode, Options>::TranslationType& translation)
328 {
329 this->translate(translation);
330 }
331
332 /**
333 * Transforms this box by \a transform and recomputes it to
334 * still be an axis-aligned box.
335 *
336 * \note This method is provided under BSD license (see the top of this file).
337 */
338 template<int Mode, int Options>
transform(const Transform<Scalar,AmbientDimAtCompileTime,Mode,Options> & transform)339 EIGEN_DEVICE_FUNC inline void transform(const Transform<Scalar, AmbientDimAtCompileTime, Mode, Options>& transform)
340 {
341 // Only Affine and Isometry transforms are currently supported.
342 EIGEN_STATIC_ASSERT(Mode == Affine || Mode == AffineCompact || Mode == Isometry, THIS_METHOD_IS_ONLY_FOR_SPECIFIC_TRANSFORMATIONS);
343
344 // Method adapted from FCL src/shape/geometric_shapes_utility.cpp#computeBV<AABB, Box>(...)
345 // https://github.com/flexible-collision-library/fcl/blob/fcl-0.4/src/shape/geometric_shapes_utility.cpp#L292
346 //
347 // Here's a nice explanation why it works: https://zeuxcg.org/2010/10/17/aabb-from-obb-with-component-wise-abs/
348
349 // two times rotated extent
350 const VectorType rotated_extent_2 = transform.linear().cwiseAbs() * sizes();
351 // two times new center
352 const VectorType rotated_center_2 = transform.linear() * (this->m_max + this->m_min) +
353 Scalar(2) * transform.translation();
354
355 this->m_max = (rotated_center_2 + rotated_extent_2) / Scalar(2);
356 this->m_min = (rotated_center_2 - rotated_extent_2) / Scalar(2);
357 }
358
359 /**
360 * \returns a copy of \c *this transformed by \a transform and recomputed to
361 * still be an axis-aligned box.
362 */
363 template<int Mode, int Options>
transformed(const Transform<Scalar,AmbientDimAtCompileTime,Mode,Options> & transform)364 EIGEN_DEVICE_FUNC AlignedBox transformed(const Transform<Scalar, AmbientDimAtCompileTime, Mode, Options>& transform) const
365 {
366 AlignedBox result(m_min, m_max);
367 result.transform(transform);
368 return result;
369 }
370
371 /** \returns \c *this with scalar type casted to \a NewScalarType
372 *
373 * Note that if \a NewScalarType is equal to the current scalar type of \c *this
374 * then this function smartly returns a const reference to \c *this.
375 */
376 template<typename NewScalarType>
377 EIGEN_DEVICE_FUNC inline typename internal::cast_return_type<AlignedBox,
cast()378 AlignedBox<NewScalarType,AmbientDimAtCompileTime> >::type cast() const
379 {
380 return typename internal::cast_return_type<AlignedBox,
381 AlignedBox<NewScalarType,AmbientDimAtCompileTime> >::type(*this);
382 }
383
384 /** Copy constructor with scalar type conversion */
385 template<typename OtherScalarType>
AlignedBox(const AlignedBox<OtherScalarType,AmbientDimAtCompileTime> & other)386 EIGEN_DEVICE_FUNC inline explicit AlignedBox(const AlignedBox<OtherScalarType,AmbientDimAtCompileTime>& other)
387 {
388 m_min = (other.min)().template cast<Scalar>();
389 m_max = (other.max)().template cast<Scalar>();
390 }
391
392 /** \returns \c true if \c *this is approximately equal to \a other, within the precision
393 * determined by \a prec.
394 *
395 * \sa MatrixBase::isApprox() */
396 EIGEN_DEVICE_FUNC bool isApprox(const AlignedBox& other, const RealScalar& prec = ScalarTraits::dummy_precision()) const
397 { return m_min.isApprox(other.m_min, prec) && m_max.isApprox(other.m_max, prec); }
398
399 protected:
400
401 VectorType m_min, m_max;
402 };
403
404
405
406 template<typename Scalar,int AmbientDim>
407 template<typename Derived>
squaredExteriorDistance(const MatrixBase<Derived> & a_p)408 EIGEN_DEVICE_FUNC inline Scalar AlignedBox<Scalar,AmbientDim>::squaredExteriorDistance(const MatrixBase<Derived>& a_p) const
409 {
410 typename internal::nested_eval<Derived,2*AmbientDim>::type p(a_p.derived());
411 Scalar dist2(0);
412 Scalar aux;
413 for (Index k=0; k<dim(); ++k)
414 {
415 if( m_min[k] > p[k] )
416 {
417 aux = m_min[k] - p[k];
418 dist2 += aux*aux;
419 }
420 else if( p[k] > m_max[k] )
421 {
422 aux = p[k] - m_max[k];
423 dist2 += aux*aux;
424 }
425 }
426 return dist2;
427 }
428
429 template<typename Scalar,int AmbientDim>
squaredExteriorDistance(const AlignedBox & b)430 EIGEN_DEVICE_FUNC inline Scalar AlignedBox<Scalar,AmbientDim>::squaredExteriorDistance(const AlignedBox& b) const
431 {
432 Scalar dist2(0);
433 Scalar aux;
434 for (Index k=0; k<dim(); ++k)
435 {
436 if( m_min[k] > b.m_max[k] )
437 {
438 aux = m_min[k] - b.m_max[k];
439 dist2 += aux*aux;
440 }
441 else if( b.m_min[k] > m_max[k] )
442 {
443 aux = b.m_min[k] - m_max[k];
444 dist2 += aux*aux;
445 }
446 }
447 return dist2;
448 }
449
450 /** \defgroup alignedboxtypedefs Global aligned box typedefs
451 *
452 * \ingroup Geometry_Module
453 *
454 * Eigen defines several typedef shortcuts for most common aligned box types.
455 *
456 * The general patterns are the following:
457 *
458 * \c AlignedBoxSizeType where \c Size can be \c 1, \c 2,\c 3,\c 4 for fixed size boxes or \c X for dynamic size,
459 * and where \c Type can be \c i for integer, \c f for float, \c d for double.
460 *
461 * For example, \c AlignedBox3d is a fixed-size 3x3 aligned box type of doubles, and \c AlignedBoxXf is a dynamic-size aligned box of floats.
462 *
463 * \sa class AlignedBox
464 */
465
466 #define EIGEN_MAKE_TYPEDEFS(Type, TypeSuffix, Size, SizeSuffix) \
467 /** \ingroup alignedboxtypedefs */ \
468 typedef AlignedBox<Type, Size> AlignedBox##SizeSuffix##TypeSuffix;
469
470 #define EIGEN_MAKE_TYPEDEFS_ALL_SIZES(Type, TypeSuffix) \
471 EIGEN_MAKE_TYPEDEFS(Type, TypeSuffix, 1, 1) \
472 EIGEN_MAKE_TYPEDEFS(Type, TypeSuffix, 2, 2) \
473 EIGEN_MAKE_TYPEDEFS(Type, TypeSuffix, 3, 3) \
474 EIGEN_MAKE_TYPEDEFS(Type, TypeSuffix, 4, 4) \
475 EIGEN_MAKE_TYPEDEFS(Type, TypeSuffix, Dynamic, X)
476
477 EIGEN_MAKE_TYPEDEFS_ALL_SIZES(int, i)
478 EIGEN_MAKE_TYPEDEFS_ALL_SIZES(float, f)
479 EIGEN_MAKE_TYPEDEFS_ALL_SIZES(double, d)
480
481 #undef EIGEN_MAKE_TYPEDEFS_ALL_SIZES
482 #undef EIGEN_MAKE_TYPEDEFS
483
484 } // end namespace Eigen
485
486 #endif // EIGEN_ALIGNEDBOX_H
487