DGtal  1.4.beta
exampleSurfaceATNormals.cpp
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1 
32 #include <iostream>
33 #include "ConfigExamples.h"
34 #include "DGtal/base/Common.h"
35 #include "DGtal/helpers/StdDefs.h"
36 #include "DGtal/helpers/Shortcuts.h"
37 #include "DGtal/helpers/ShortcutsGeometry.h"
38 #include "DGtal/dec/ATSolver2D.h"
39 #include "DGtal/dec/DiscreteExteriorCalculusFactory.h"
42 
43 using namespace std;
44 using namespace DGtal;
45 
47 
48 int main( int argc, char** argv )
49 {
50  typedef Z3i::KSpace KSpace;
51  typedef Shortcuts< KSpace > SH3;
53  typedef SH3::Cell Cell;
54 
55  const double alpha_at = 0.1;
56  const double lambda_at = 0.01;
57  const double e1 = 2.0;
58  const double e2 = 0.25;
59  const double er = 2.0;
60 
61  const string volfile = argc > 1 ? argv[ 1 ] : examplesPath + "samples/Al.100.vol";
62  const double threshold = argc > 2 ? atof( argv[ 2 ] ) : 0.5;
63  trace.beginBlock ( "Load vol file -> build digital surface -> estimate II normals." );
65  auto params = SH3::defaultParameters() | SHG3::defaultParameters();
66  auto bimage = SH3::makeBinaryImage( volfile, params );
67  auto K = SH3::getKSpace( bimage, params );
68  auto surface = SH3::makeDigitalSurface( bimage, K, params );
69  auto surfels = SH3::getSurfelRange( surface, params );
70  auto linels = SH3::getCellRange( surface, 1 );
71  auto ii_normals= SHG3::getIINormalVectors( bimage, surfels, params );
72  auto uembedder = SH3::getCellEmbedder( K );
73  auto embedder = SH3::getSCellEmbedder( K );
75  trace.endBlock();
76 
77  trace.beginBlock ( "Creating AT solver for digital surface" );
80  const auto calculus = CalculusFactory::createFromNSCells<2>( surfels.begin(), surfels.end() );
83  ATSolver2D< KSpace > at_solver(calculus, 1);
84  at_solver.initInputVectorFieldU2( ii_normals, surfels.cbegin(), surfels.cend() );
85  at_solver.setUp( alpha_at, lambda_at );
86  at_solver.solveGammaConvergence( e1, e2, er );
88  trace.endBlock();
89 
90  trace.beginBlock ( "Save AT normals as OBJ file" );
92  auto at_normals = ii_normals;
93  at_solver.getOutputVectorFieldU2( at_normals, surfels.cbegin(), surfels.cend() );
95  SH3::RealPoints positions( surfels.size() );
96  std::transform( surfels.cbegin(), surfels.cend(), positions.begin(),
97  [&] (const SH3::SCell& c) { return embedder( c ); } );
98  SH3::Colors colors( surfels.size() );
99  for ( size_t i = 0; i < surfels.size(); i++ )
100  colors[ i ] = SH3::Color( (unsigned char) 255.0*fabs( at_normals[ i ][ 0 ] ),
101  (unsigned char) 255.0*fabs( at_normals[ i ][ 1 ] ),
102  (unsigned char) 255.0*fabs( at_normals[ i ][ 2 ] ) );
103  std::transform( surfels.cbegin(), surfels.cend(), positions.begin(),
104  [&] (const SH3::SCell& c) { return embedder( c ); } );
105 
106  bool ok1 = SH3::saveOBJ( surface, at_normals, SH3::Colors(),
107  "output-surface.obj" );
108  bool ok2 = SH3::saveOBJ( surface, at_normals, colors,
109  "output-surface-at-normals.obj" );
110  bool ok3 = SH3::saveVectorFieldOBJ( positions, at_normals, 0.05, SH3::Colors(),
111  "output-vf-at-normals.obj",
112  SH3::Color( 0, 0, 0 ), SH3::Color::Red );
113 
114  ASSERT(ok1 && ok2 && ok3);
116  SH3::Scalars features( linels.size() );
117  at_solver.getOutputScalarFieldV0( features, linels.cbegin(), linels.cend(),
118  at_solver.Maximum );
120  SH3::RealPoints f0;
121  SH3::RealVectors f1;
122  for ( size_t i = 0; i < linels.size(); i++ )
123  {
124  if ( features[ i ] < threshold )
125  {
126  const Cell linel = linels[ i ];
127  const Dimension d = * K.uDirs( linel );
128  const Cell p0 = K.uIncident( linel, d, false );
129  const Cell p1 = K.uIncident( linel, d, true );
130  f0.push_back( uembedder( p0 ) );
131  f1.push_back( uembedder( p1 ) - uembedder( p0 ) );
132  }
133  }
134  bool ok4 = SH3::saveVectorFieldOBJ( f0, f1, 0.1, SH3::Colors(),
135  "output-features.obj",
136  SH3::Color( 0, 0, 0 ), SH3::Color::Red );
137 
138  ASSERT(ok4);
139  trace.endBlock();
140  return 0;
141 }
142 // //
Aim: This class solves Ambrosio-Tortorelli functional on a two-dimensional digital space (a 2D grid o...
Definition: ATSolver2D.h:91
void getOutputScalarFieldV0(ScalarFieldOutput &output, CellRangeConstIterator itB, CellRangeConstIterator itE, CellOutputPolicy policy=CellOutputPolicy::Average)
Definition: ATSolver2D.h:824
void setUp(double a, double l)
Definition: ATSolver2D.h:444
void initInputVectorFieldU2(const VectorFieldInput &input, SurfelRangeConstIterator itB, SurfelRangeConstIterator itE, bool normalize=false)
Definition: ATSolver2D.h:288
bool solveGammaConvergence(double eps1=2.0, double eps2=0.25, double epsr=2.0, bool compute_smallest_epsilon_map=false, double n_oo_max=1e-4, unsigned int iter_max=10)
Definition: ATSolver2D.h:657
void getOutputVectorFieldU2(VectorFieldOutput &output, SurfelRangeConstIterator itB, SurfelRangeConstIterator itE)
Definition: ATSolver2D.h:772
@ Maximum
compute maximum value at cell vertices
Definition: ATSolver2D.h:105
Structure representing an RGB triple with alpha component.
Definition: Color.h:68
static const Color Red
Definition: Color.h:416
Aim: This class provides static members to create DEC structures from various other DGtal structures.
Aim: This class is a model of CCellularGridSpaceND. It represents the cubical grid as a cell complex,...
Cell uIncident(const Cell &c, Dimension k, bool up) const
Return the forward or backward unsigned cell incident to [c] along axis [k], depending on [up].
DirIterator uDirs(const Cell &p) const
Given an unsigned cell [p], returns an iterator to iterate over each coordinate the cell spans.
Aim: This class is used to simplify shape and surface creation. With it, you can create new shapes an...
Aim: This class is used to simplify shape and surface creation. With it, you can create new shapes an...
Definition: Shortcuts.h:105
std::vector< Color > Colors
Definition: Shortcuts.h:192
std::vector< RealPoint > RealPoints
Definition: Shortcuts.h:180
std::vector< RealVector > RealVectors
Definition: Shortcuts.h:179
std::vector< Scalar > Scalars
Definition: Shortcuts.h:178
LightDigitalSurface::SCell SCell
Definition: Shortcuts.h:163
LightDigitalSurface::Cell Cell
Definition: Shortcuts.h:162
void beginBlock(const std::string &keyword="")
double endBlock()
int main(int argc, char **argv)
DGtal is the top-level namespace which contains all DGtal functions and types.
DGtal::uint32_t Dimension
Definition: Common.h:136
Trace trace
Definition: Common.h:153
Shortcuts< KSpace > SH3
KSpace K
KSpace::Cell Cell
ShortcutsGeometry< Z3i::KSpace > SHG3