Add OpenGR Wrapper for Multiple Point Cloud Registration

.gitignore

@@ -1,3 +1,4 @@
+.vscode/*
 /*build*
 /*/*/*/build
 AABB_tree/demo/AABB_tree/AABB_demo

Documentation/doc/biblio/cgal_manual.bib

@@ -405,6 +405,15 @@ @inproceedings{cgal:cdr-drpsc-07
  address = {Philadelphia, PA, USA},
  }
 
+ @article { cgal:cks-grmpcsp
+  author    = {Kunal N. Chaudhury and Yuehaw Khoo and Amit Singer and David Cowburn},
+  title     = {Global registration of multiple point clouds using semidefinite programming},
+  journal   = {CoRR},
+  volume    = {abs/1306.5226},
+  year      = {2013},
+  url       = {http://arxiv.org/abs/1306.5226}
+}
+
 @inproceedings{ cgal:cl-vmbcm-96
   ,author       = {Brian Curless and Marc Levoy}
   ,title        = {A Volumetric Method for Building Complex

Point_set_processing_3/doc/Point_set_processing_3/PackageDescription.txt

@@ -53,6 +53,8 @@ format.
 - `CGAL::estimate_local_range_scales()`
 - `CGAL::OpenGR::compute_registration_transformation()`
 - `CGAL::OpenGR::register_point_sets()`
+- `CGAL::OpenGR::compute_registration_transformations()`
+- `CGAL::OpenGR::register_point_clouds()`
 - `CGAL::pointmatcher::compute_registration_transformation()`
 - `CGAL::pointmatcher::register_point_sets()`
 - `CGAL::remove_outliers()`

Point_set_processing_3/doc/Point_set_processing_3/Point_set_processing_3.txt

@@ -420,6 +420,14 @@ Maximum number of seconds after which the algorithm stops. Super4PCS explores th
 transformation space to align the two input clouds. Since the exploration is performed
 randomly, it is recommended to use a large time value to explore the whole space.
 
+
+\subsection Point_set_processing_3Examples_registration_OpenGR_GRET_SDP OpenGR GRET-SDP Example
+GRET-SDP is an registration algorithm for multiple point clouds that is described in [this paper](https://arxiv.org/abs/1306.5226). 
+It is important to note that for each point, its corresponding points (e.g. points that represent the same location in space) in the other point clouds have to be known. 
+
+The following example reads N point clouds from a stanford config file, computes their correspondences and alignes them using the GRET-SDP algorithm from OpenGR. 
+\cgalExample{Point_set_processing_3/registration_with_OpenGR_using_GRET_SDP.cpp}
+
 \subsection Point_set_processing_3Examples_registration_PointMatcher PointMatcher Example
 
 The following example reads two point sets and aligns them using the

Point_set_processing_3/doc/Point_set_processing_3/examples.txt

@@ -22,4 +22,5 @@
 \example Point_set_processing_3/edges_example.cpp
 \example Point_set_processing_3/structuring_example.cpp
 \example Point_set_processing_3/callback_example.cpp
+\example Point_set_processing_3/registration_with_OpenGR_using_GRET_SDP.cpp
 */

Point_set_processing_3/examples/Point_set_processing_3/CMakeLists.txt

@@ -86,7 +86,7 @@ if ( CGAL_FOUND )
         hierarchy_simplification_example
         normals_example)
       add_executable(${target} "${target}.cpp")
-      target_link_libraries(${target} ${CGAL_libs})
+      target_link_libraries(${target} ${CGAL_libs} )
     endforeach()
 
     # Executables that require libpointmatcher
@@ -104,6 +104,31 @@ if ( CGAL_FOUND )
     find_package(OpenGR QUIET)
     include(CGAL_OpenGR_support)
     if (TARGET CGAL::OpenGR_support)
+
+      # GRET SDP
+      find_package(Boost 1.54 COMPONENTS system filesystem  REQUIRED)
+      if (Boost_FOUND)    
+      set(GRET_SDP_DATA_DIR_TO ${CMAKE_CURRENT_BINARY_DIR}/data)
+      set(GRET_SDP_DATA_DIR_FROM ${PROJECT_SOURCE_DIR}/data/)
+      add_custom_target(copy_gret_sdp_data)
+      add_custom_command(TARGET copy_gret_sdp_data
+      POST_BUILD
+      COMMAND ${CMAKE_COMMAND} -E make_directory ${GRET_SDP_DATA_DIR_TO}
+      COMMAND ${CMAKE_COMMAND} -E copy ${GRET_SDP_DATA_DIR_FROM}/bun.conf ${GRET_SDP_DATA_DIR_TO}/.
+      COMMAND ${CMAKE_COMMAND} -E copy ${GRET_SDP_DATA_DIR_FROM}/bun*.ply ${GRET_SDP_DATA_DIR_TO}/.
+      )
+
+      find_package(SDPA REQUIRED)
+      include_directories(${SDPA_INCLUDE_DIRS})
+      include_directories(${Boost_INCLUDE_DIRS})
+      add_executable(registration_with_OpenGR_using_GRET_SDP "registration_with_OpenGR_using_GRET_SDP.cpp" )
+      target_link_libraries(registration_with_OpenGR_using_GRET_SDP
+      ${CGAL_libs} CGAL::OpenGR_support ${SDPA_LIBRARIES} ${Boost_FILESYSTEM_LIBRARY} ${Boost_SYSTEM_LIBRARY})
+      target_compile_definitions(registration_with_OpenGR_using_GRET_SDP PUBLIC OpenGR_USE_SDPA)
+      add_dependencies(registration_with_OpenGR_using_GRET_SDP copy_gret_sdp_data)
+      endif(Boost_FOUND)
+
+      # SUPER4PC
       add_executable(registration_with_OpenGR "registration_with_OpenGR.cpp" )
       target_link_libraries(registration_with_OpenGR
         ${CGAL_libs} CGAL::OpenGR_support)

Point_set_processing_3/examples/Point_set_processing_3/data/bun.conf

@@ -0,0 +1,3 @@
+bmesh bun000.ply 0 0 0 0 0 0 1
+bmesh bun045.ply -0.0520211 -0.000383981 -0.0109223 0.00548449 -0.294635 -0.0038555 0.955586
+bmesh bun090.ply 2.20761e-05 -3.34606e-05 -7.20881e-05 0.000335889 -0.708202 0.000602459 0.706009