Light Cell Geometry

ChangeLog.md

@@ -16,8 +16,13 @@
 - *Geometry Package*
   - New piecewise smooth digital surface regularization class (David Coeurjolly,
   [#1440](https://github.com/DGtal-team/DGtal/pull/1440))
-  - Provides support for digital full convexity and subconvexity (Jacques-Olivier Lachaud,
-  [#1459](https://github.com/DGtal-team/DGtal/pull/1459))
+  - Provides support for digital full convexity and subconvexity
+    (Jacques-Olivier Lachaud,
+    [#1459](https://github.com/DGtal-team/DGtal/pull/1459))
+  - Updates cell geometry and digital convexity to use specialized
+    unordered set data structure UnorderedSetByBlock for storing
+    digital points (Jacques-Olivier Lachaud,
+    [#1499](https://github.com/DGtal-team/DGtal/pull/1499))
 
 ## Changes
 
@@ -49,6 +54,10 @@
 - *Kernel package*
   - Add .data() function to PointVector to expose internal array data.
     (Pablo Hernandez-Cerdan, [#1452](https://github.com/DGtal-team/DGtal/pull/1452))
+  - Add a specialized unordered set data structure
+    UnorderedSetByBlock for storing digital points, which is more
+    compact and as efficient as unordered set
+    (Jacques-Olivier Lachaud,[#1499](https://github.com/DGtal-team/DGtal/pull/1499))
 
 - *Helpers*
   - Add vector field output as OBJ to module Shortcuts (Jacques-Olivier Lachaud,

examples/geometry/curves/exampleDigitalConvexity.cpp

@@ -35,7 +35,7 @@
    @see \ref moduleDigitalConvexity
 
    \image html grid-curve-dig-convexity.png "Extraction of all subconvex triangles to the digital curve."
-   
+
    \example geometry/curves/exampleDigitalConvexity.cpp
 */
 
@@ -57,54 +57,51 @@
 
 using namespace std;
 using namespace DGtal;
-using namespace Z2i; 
+using namespace Z2i;
 
 
 ///////////////////////////////////////////////////////////////////////////////
 int main( int argc, char** argv )
 {
   trace.beginBlock ( "Example for 2d gridcurves" );
   string S = examplesPath + "samples/contourS.fc";
-  
+
   // domain
   const Point lowerBound( -200, -200 );
   const Point upperBound( 200, 200 );
 
   fstream inputStream( S.c_str(), ios::in );
   FreemanChain<int> fc(inputStream);
   inputStream.close();
-  Curve c; 
-  c.initFromPointsRange( fc.begin(), fc.end() ); 
+  Curve c;
+  c.initFromPointsRange( fc.begin(), fc.end() );
   auto points = c.getPointsRange();
   std::vector<Point> T( points.begin(), points.end() );
   Board2D aBoard;
   aBoard.setUnit(Board2D::UCentimeter);
   DigitalConvexity<KSpace> dconv( lowerBound, upperBound );
   auto c_cover = dconv.makeCellCover( T.begin(), T.end(), 1, 1 );
-  trace.beginBlock( "Prepare subset operations" );
-  c_cover.prepareSubsetOperations();
-  trace.endBlock();
   const float sx = -0.5;
   const float sy = -0.5;
   trace.beginBlock( "Compute fully subconvex sets" );
   for ( unsigned int i = 0; i < T.size(); ++i )
     for ( unsigned int j = i+2; j < T.size(); ++j )
       {
-	aBoard.setPenColorRGBi( rand() % 255, rand() % 255, rand() % 255 );
-	unsigned int k = (i+j)/2;
-	if ( ! dconv.isSimplexFullDimensional( { T[i], T[j], T[k] } ) ) continue;
-	auto triangle = dconv.makeSimplex( { T[i], T[j], T[k] } );
-	if ( dconv.isFullySubconvex( triangle, c_cover ) )
-	  {
-	    aBoard.drawLine( sx+(float)T[i][0], sy+(float)T[i][1],
-			     sx+(float)T[j][0], sy+(float)T[j][1] );
-	    aBoard.drawLine( sx+(float)T[i][0], sy+(float)T[i][1],
-			     sx+(float)T[k][0], sy+(float)T[k][1] );
-	    aBoard.drawLine( sx+(float)T[k][0], sy+(float)T[k][1],
-			     sx+(float)T[j][0], sy+(float)T[j][1] );
-	  }
-	else
-	  j = T.size();
+        aBoard.setPenColorRGBi( rand() % 255, rand() % 255, rand() % 255 );
+        unsigned int k = (i+j)/2;
+        if ( ! dconv.isSimplexFullDimensional( { T[i], T[j], T[k] } ) ) continue;
+        auto triangle = dconv.makeSimplex( { T[i], T[j], T[k] } );
+        if ( dconv.isFullySubconvex( triangle, c_cover ) )
+          {
+            aBoard.drawLine( sx+(float)T[i][0], sy+(float)T[i][1],
+                             sx+(float)T[j][0], sy+(float)T[j][1] );
+            aBoard.drawLine( sx+(float)T[i][0], sy+(float)T[i][1],
+                             sx+(float)T[k][0], sy+(float)T[k][1] );
+            aBoard.drawLine( sx+(float)T[k][0], sy+(float)T[k][1],
+                             sx+(float)T[j][0], sy+(float)T[j][1] );
+          }
+        else
+          j = T.size();
       }
   trace.endBlock();
   aBoard.setPenColor( Color::Black );

examples/geometry/curves/exampleRationalConvexity.cpp

@@ -35,7 +35,7 @@
    @see \ref moduleDigitalConvexity
 
    \image html grid-curve-subconvex-rational-segment.png "Extraction of all maximal rational segments between midpoints that are subconvex to the digital curve."
-   
+
    \example geometry/curves/exampleRationalConvexity.cpp
 */
 
@@ -58,25 +58,25 @@
 
 using namespace std;
 using namespace DGtal;
-using namespace Z2i; 
+using namespace Z2i;
 
 
 ///////////////////////////////////////////////////////////////////////////////
 int main( int argc, char** argv )
 {
   trace.beginBlock ( "Example for 2d gridcurves" );
   string S = examplesPath + "samples/contourS.fc";
-  
+
   // domain
   const Point lowerBound( -200, -200 );
   const Point upperBound( 200, 200 );
   DigitalConvexity<KSpace> dconv( lowerBound, upperBound );
-  
+
   fstream inputStream( S.c_str(), ios::in );
   FreemanChain<int> fc(inputStream);
   inputStream.close();
-  Curve c; 
-  c.initFromPointsRange( fc.begin(), fc.end() ); 
+  Curve c;
+  c.initFromPointsRange( fc.begin(), fc.end() );
   auto points = c.getPointsRange();
   std::vector<Point> T( points.begin(), points.end() );
   auto midpoints = c.getMidPointsRange();
@@ -85,7 +85,7 @@ int main( int argc, char** argv )
   for ( auto && rp : midpoints )
     // there is a shift of (0.5,0.5) between points and cells embedder.
     T2.push_back( Point( (int) round( 2. * rp[ 0 ] + 1. ),
-			 (int) round( 2. * rp[ 1 ] + 1. ) ) );
+                         (int) round( 2. * rp[ 1 ] + 1. ) ) );
   Board2D aBoard;
   aBoard.setUnit(Board2D::UCentimeter);
   // Display cells
@@ -101,15 +101,12 @@ int main( int argc, char** argv )
     }
   for ( auto && pixel : pixels )
     aBoard << CustomStyle( pixel.className(), new CustomColors( grey, grey ) )
-	   << pixel;
+           << pixel;
   // Display contour
   aBoard.setPenColor( Color::Black );
   aBoard << c;
   // Compute subconvex rational segments.
   auto    c_cover = dconv.makeCellCover( T.begin(), T.end(), 1, 1 );
-  trace.beginBlock( "Prepare subset operations" );
-  c_cover.prepareSubsetOperations();
-  trace.endBlock();
   trace.beginBlock( "Compute fully subconvex rational sets" );
   Point denominator( 2, 2 );
   unsigned int last_j = 0;
@@ -119,16 +116,16 @@ int main( int argc, char** argv )
       aBoard.setPenColorRGBi( rand() % 255, rand() % 255, rand() % 255 );
       unsigned int start_j = ( i + 1 ) % T2.size();
       for ( j = ( start_j + 1 ) % T2.size(); j != start_j;  j = ( j + 1 ) % T2.size() )
-	{
-	  auto segment = dconv.makeRationalSimplex( { denominator, T2[i], T2[j] } );
-	  if ( ! dconv.isFullySubconvex( segment, c_cover ) ) break;
-	}
+        {
+          auto segment = dconv.makeRationalSimplex( { denominator, T2[i], T2[j] } );
+          if ( ! dconv.isFullySubconvex( segment, c_cover ) ) break;
+        }
       j = ( j + T2.size() - 1 ) % T2.size();
-      if ( j != last_j ) 
-	{ // display fully subconvex segments
-	  aBoard.setLineWidth( 2.5 );
-	  aBoard.drawLine( RT[i][0], RT[i][1], RT[j][0], RT[j][1] );
-	}
+      if ( j != last_j )
+        { // display fully subconvex segments
+          aBoard.setLineWidth( 2.5 );
+          aBoard.drawLine( RT[i][0], RT[i][1], RT[j][0], RT[j][1] );
+        }
       last_j = j;
     }
   trace.endBlock();

src/DGtal/geometry/doc/moduleDigitalConvexity.dox

@@ -166,9 +166,10 @@ Lattice point retrieval services:
 
 The class CellGeometry can compute and store set of lattice cells of
 different dimensions. You specify at construction a Khalimsky space
-(any model of concepts::CCellularGridSpaceND) or a CubicalComplex, as well as the
+(any model of concepts::CCellularGridSpaceND), as well as the
 dimensions of the cells you are interested in. Internally it uses a
-CubicalComplex to store the lattice cells.
+variant of unordered set of points (see \ref UnorderedSetByBlock) to
+store the lattice cells in a compact manner.
 
 \code
 #include "DGtal/geometry/volumes/CellGeometry.h"
@@ -181,7 +182,7 @@ CellGeometry< KSpace > cell_geometry( K, 1, 2 ); // only 1-cells and 2-cells
 
 Then you may add cells that touch a range of points, or cells
 intersected by a polytope, or cells belonging to another CellGeometry
-object, or cells belonging to a CubicalComplex.
+object.
 
 - CellGeometry::addCellsTouchingPoints: Updates the cell cover with
   the cells touching a range of digital points [itB, itE).
@@ -195,9 +196,6 @@ object, or cells belonging to a CubicalComplex.
 - CellGeometry::operator+=( const CellGeometry& other ): Adds the
   cells of dimension k of object \a other, for `minCellDim() <= k <=
   maxCellDim()`, to this cell geometry.
-- CellGeometry::operator+=( const CubicalComplex& CC ): Adds the cells
-  of dimension k of cubical complex \a CC, for `minCellDim() <= k <=
-  maxCellDim()`, to this cell geometry.
 
 With respect to full digital convexity,
 CellGeometry::addCellsTouchingPolytope is very important since it
@@ -299,7 +297,7 @@ The class BoundedLatticePolytope is different from the class LatticePolytope2D f
 There are no simple conversion from one to the other. Class
 LatticePolytope2D is optimized for cuts and lattice points
 enumeration, and is very specific to 2D. Class BoundedLatticePolytope
-is less optimized to the previous one but works in nD and provides
+is less optimized than the previous one but works in nD and provides
 Minkowski sum and dilation services.