Line data Source code
1 : /*
2 : * Copyright (c) 2015: G-CSC, Goethe University Frankfurt
3 : * Author: Sebastian Reiter
4 : *
5 : * This file is part of UG4.
6 : *
7 : * UG4 is free software: you can redistribute it and/or modify it under the
8 : * terms of the GNU Lesser General Public License version 3 (as published by the
9 : * Free Software Foundation) with the following additional attribution
10 : * requirements (according to LGPL/GPL v3 §7):
11 : *
12 : * (1) The following notice must be displayed in the Appropriate Legal Notices
13 : * of covered and combined works: "Based on UG4 (www.ug4.org/license)".
14 : *
15 : * (2) The following notice must be displayed at a prominent place in the
16 : * terminal output of covered works: "Based on UG4 (www.ug4.org/license)".
17 : *
18 : * (3) The following bibliography is recommended for citation and must be
19 : * preserved in all covered files:
20 : * "Reiter, S., Vogel, A., Heppner, I., Rupp, M., and Wittum, G. A massively
21 : * parallel geometric multigrid solver on hierarchically distributed grids.
22 : * Computing and visualization in science 16, 4 (2013), 151-164"
23 : * "Vogel, A., Reiter, S., Rupp, M., Nägel, A., and Wittum, G. UG4 -- a novel
24 : * flexible software system for simulating pde based models on high performance
25 : * computers. Computing and visualization in science 16, 4 (2013), 165-179"
26 : *
27 : * This program is distributed in the hope that it will be useful,
28 : * but WITHOUT ANY WARRANTY; without even the implied warranty of
29 : * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
30 : * GNU Lesser General Public License for more details.
31 : */
32 :
33 : #ifndef __H__UG_heightfield_util
34 : #define __H__UG_heightfield_util
35 :
36 : #include "lib_grid/lg_base.h"
37 : #include "common/util/field.h"
38 : #include "common/boost_serialization.h"
39 :
40 : namespace ug{
41 :
42 : ////////////////////////////////////////////////////////////////////////////////
43 : /// A heightfield represents a grid of number-values together with descriptors for
44 : /// the cell dimensions and the total offset.
45 : /** You can manually create heightfields or load them from a file. Given a heightfield
46 : * you may create a quad/tri grid or extract the heightfields boundary into a grid.
47 : * Have a look at field_util.h, too, which declares some useful functions (e.g. blurring).
48 : * \sa LoadHeightfieldFromASC, CreateGridFromField, CreateGridFromFieldBoundary
49 : */
50 0 : UG_API class Heightfield{
51 : public:
52 : Heightfield();
53 :
54 : /// returns the interpolated value at the given location.
55 : /** returns the interpolated value at the given location. Through 'interpOrder'
56 : * one may specify the order of interpolation:
57 : * - 0: piecewise constant (nearest entry)
58 : * - 1: linear
59 : *
60 : * \todo: add a method 'set_interpolation_method' to also support
61 : * bilinear- or spline-interpolation
62 : * \{ */
63 :
64 : number interpolate (number x, number y, int interpOrder) const;
65 :
66 : number interpolate (const vector2& c, int interpOrder) const
67 : {
68 0 : return interpolate(c.x(), c.y(), interpOrder);
69 : }
70 :
71 0 : number interpolate (number x, number y) const
72 : {
73 0 : return interpolate(x, y, 0);
74 : }
75 :
76 : number interpolate (const vector2& c) const
77 : {
78 0 : return interpolate(c.x(), c.y(), 0);
79 : }
80 : /** \} */
81 :
82 :
83 :
84 : /// returns the index-tuple of the closest field-entry
85 : std::pair<int, int> coordinate_to_index(number x, number y) const;
86 :
87 : /// returns the coordinate of the given cell (specified through an index-tuple)
88 : vector2 index_to_coordinate(int ix, int iy) const;
89 :
90 : /// returns the x- and y-extent of the heightfield
91 : vector2 extent() const;
92 :
93 0 : Field<number>& field() {return m_field;}
94 0 : const Field<number>& field() const {return m_field;}
95 :
96 0 : const vector2& cell_size() const {return m_cellSize;}
97 : void set_cell_size(const vector2& s) {m_cellSize = s;}
98 :
99 0 : const vector2& offset() const {return m_offset;}
100 : void set_offset(const vector2& o) {m_offset = o;}
101 :
102 0 : number no_data_value() const {return m_noDataValue;}
103 0 : void set_no_data_value(number val) {m_noDataValue = val;}
104 :
105 : // moves the heightfield by altering it's offset
106 : void move(const vector2& v) {m_offset += v;}
107 :
108 : /// Smoothens the field by adjusting the value of each pixel towards the average of its neighbours
109 : void blur(number alpha, size_t numIterations);
110 :
111 : /// eliminates invalid cells by repeatedly filling those cells with averages of neighboring cells
112 : /** The field has to contain at least one valid cell. If it doesn't, false is returned.*/
113 : bool eliminate_invalid_cells();
114 :
115 : private:
116 : // BEGIN SERIALIZATION
117 : friend class boost::serialization::access;
118 :
119 : template <class Archive>
120 0 : void serialize( Archive& ar, const unsigned int version)
121 : {
122 0 : ar & m_cellSize;
123 0 : ar & m_offset;
124 0 : ar & m_noDataValue;
125 0 : ar & m_field;
126 0 : }
127 : // END SERIALIZATION
128 :
129 :
130 : Field<number> m_field;
131 : vector2 m_cellSize;
132 : vector2 m_offset;
133 : number m_noDataValue;
134 : };
135 :
136 :
137 : ////////////////////////////////////////////////////////////////////////////////
138 : void UG_API
139 : LoadHeightfieldFromASC(Heightfield& field, const char* filename);
140 :
141 : ////////////////////////////////////////////////////////////////////////////////
142 : void UG_API
143 : CreateGridFromField(Grid& grid,
144 : const Heightfield& hfield,
145 : Grid::VertexAttachmentAccessor<APosition> aaPos);
146 :
147 : ////////////////////////////////////////////////////////////////////////////////
148 : void UG_API
149 : CreateGridFromFieldBoundary(Grid& grid,
150 : const Heightfield& hfield,
151 : Grid::VertexAttachmentAccessor<APosition> aaPos);
152 :
153 : }// end of namespace
154 :
155 : #endif //__H__UG_heightfield_util
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