1 /*=========================================================================
2  *
3  *  Copyright Insight Software Consortium
4  *
5  *  Licensed under the Apache License, Version 2.0 (the "License");
6  *  you may not use this file except in compliance with the License.
7  *  You may obtain a copy of the License at
8  *
9  *         http://www.apache.org/licenses/LICENSE-2.0.txt
10  *
11  *  Unless required by applicable law or agreed to in writing, software
12  *  distributed under the License is distributed on an "AS IS" BASIS,
13  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14  *  See the License for the specific language governing permissions and
15  *  limitations under the License.
16  *
17  *=========================================================================*/
18 #ifndef itkSpatialFunction_h
19 #define itkSpatialFunction_h
20 
21 #include "itkFunctionBase.h"
22 #include "itkPoint.h"
23 
24 namespace itk
25 {
26 /** \class SpatialFunction
27  * \brief N-dimensional spatial function class
28  *
29  * itk::SpatialFunction provides the ability to define functions that can
30  * be evaluated at an arbitrary point in space (physical or otherwise). The return
31  * type is specified by the derived class, and the input to the function
32  * is an n-dimensional itk::Point.
33  *
34  * Although itk::ImageFunction and itk::SpatialFunction are quite similar,
35  * itk::SpatialFunction derived classes exist without reference to an Image
36  * type.
37  *
38  * SpatialFunction is templated over output type (the data type
39  * returned by an evaluate() call) and dimensionality.
40  *
41  * \ingroup SpatialFunctions
42  * \ingroup ITKCommon
43  */
44 template< typename TOutput,
45           unsigned int VImageDimension = 3,
46           typename TInput = Point< double, VImageDimension > >
47 class ITK_TEMPLATE_EXPORT SpatialFunction:public FunctionBase< TInput, TOutput >
48 {
49 public:
50   ITK_DISALLOW_COPY_AND_ASSIGN(SpatialFunction);
51 
52   /** Standard class type aliases. */
53   using Self = SpatialFunction;
54   using Superclass = FunctionBase< TInput, TOutput >;
55   using Pointer = SmartPointer< Self >;
56   using ConstPointer = SmartPointer< const Self >;
57 
58   /** Run-time type information (and related methods). */
59   itkTypeMacro(SpatialFunction, FunctionBase);
60 
61   /** Input type for the function. */
62   using InputType = typename Superclass::InputType;
63 
64   /** Output type for the function. */
65   using OutputType = typename Superclass::OutputType;
66 
67   /** Spatial dimension. */
68   static constexpr unsigned int ImageDimension = VImageDimension;
69 
70   /** Evaluate the function at a given position. Remember, position is
71   * represented by an n-d itk::Point object with data type double. */
72   OutputType Evaluate(const InputType & input) const override = 0;
73 
74 protected:
75   SpatialFunction() = default;
76   ~SpatialFunction() override = default;
77   void PrintSelf(std::ostream & os, Indent indent) const override;
78 };
79 } // end namespace itk
80 
81 #ifndef ITK_MANUAL_INSTANTIATION
82 #include "itkSpatialFunction.hxx"
83 #endif
84 
85 #endif
86