Add FlannIndex abstract interface and implement NanoFlannIndex subclass (#1744)

* Add FlannIndex abstract interface and implement NanoFlannIndex subclass

* Refactored: made NanoFlann a new NN type instead of inheriting FlannIndex. Added tests. Vendoring nanoflann.h directly in the repo. RegistrationVis now use NANOFLANN_INDEX_KDTREE_SINGLE (instead of FLANN_INDEX_KDTREE_SINGLE) flann index for 2d points matching.

* cleanup comments, added FlannIndex doxygen

* Fixing windows tests

* updating flaky test

* Simplified interface, added flann kdtree single approach selectable by parameters.

* RegVis: symmetry of nanoflann for two branches of guess feature matching

* cv::BFMatcher baseline

* Small cmake optimization FLANN_KDTREE_MEM_OPT only defined for FlannIndex

* Refactored where FLANN_KDTREE_MEM_OPT is defined

* fixed file name already exist

* cleanup

* fixup build

---------

Co-authored-by: matlabbe <matlabbe@gmail.com>

.github/workflows/cmake-linux.yml

@@ -101,4 +101,4 @@ jobs:
       env:
         PYTHONNOUSERSITE: 1
       run: |
-        ctest -C ${{env.BUILD_TYPE}} -V
+        ctest -C ${{env.BUILD_TYPE}} -V -LE performance

.github/workflows/cmake-macos.yml

@@ -124,7 +124,7 @@ jobs:
       env:
         PYTHONNOUSERSITE: 1
       run: |
-        ctest -C ${{env.BUILD_TYPE}} -V
+        ctest -C ${{env.BUILD_TYPE}} -V -LE performance
 
     # A ctest SEGFAULT is reported as just "SEGFAULT" with no backtrace, which
     # makes a crash inside a long integration test invisible -- the log simply

.github/workflows/cmake-windows.yml

@@ -125,7 +125,7 @@ jobs:
         PYTHONHOME: ${{env.VCPKG_EXPORT_PATH}}/installed/x64-windows-release/tools/python3
         PYTHONNOUSERSITE: 1
       run: |
-        ctest -C ${{env.BUILD_TYPE}} -V --timeout 300
+        ctest -C ${{env.BUILD_TYPE}} -V --timeout 300 -LE performance
 
     - name: Info
       # Skipped for CUDA: the binary links ZED (sl_zed64.dll -> nvcuvid/nvEncodeAPI64),

.github/workflows/coverage.yml

@@ -128,7 +128,7 @@ jobs:
           #
           # The replays still run (and gate) in the cmake-linux / macos /
           # windows jobs; they are just not measured here.
-          ctest -V -LE long
+          ctest -V -LE "long|performance"
 
       - name: Generate LCOV report
         run: |