Guard the levelset rebuild oracle behind a #define. There are issues

when increasing resolution.  We still include it because we want
anyone who thinks of trying this approach in the future to have an
example and some documentation of what goes wrong.

Add explicit instantiation for oracle-less meshToVolume, which should
allow the explicit template builds to work.

Signed-off-by: Jeff Lait <jlait@andorra.sidefx.com>

Author: jmlait

openvdb/openvdb/tools/LevelSetRebuild.h

@@ -4,13 +4,25 @@
 #ifndef OPENVDB_TOOLS_LEVELSETREBUILD_HAS_BEEN_INCLUDED
 #define OPENVDB_TOOLS_LEVELSETREBUILD_HAS_BEEN_INCLUDED
 
+/// When rebuilding we convert from grid -> mesh -> grid.
+/// The conversion from mesh -> grid will close any internal bubbles.
+/// By using the original grid as an oracle we can set the sign of the
+/// bubbles properly.  Unfortunately, when increasing resolution the 
+/// rasterization of the mesh diverges too far from interpolated original
+/// grid and results in incorrect sign choices.   The likely correct solution
+/// is to use a different approach for rebuilding when resolution is
+/// increasing.
+#define OPENVDB_USE_ORACLE_IN_REBUILD 0
+
 #include <openvdb/Grid.h>
 #include <openvdb/Exceptions.h>
 #include <openvdb/math/Math.h>
 #include <openvdb/math/Transform.h>
+#if OPENVDB_USE_ORACLE_IN_REBUILD
 #include <openvdb/tools/VolumeToMesh.h>
 #include <openvdb/tools/MeshToVolume.h>
 #include <openvdb/tools/Interpolation.h>
+#endif
 #include <openvdb/util/NullInterrupter.h>
 #include <openvdb/util/Util.h>
 #include <openvdb/openvdb.h>
@@ -253,6 +265,7 @@ doLevelSetRebuild(const GridType& grid, typename GridType::ValueType iso,
 
     QuadAndTriangleDataAdapter<Vec3s, Vec4I> mesh(points, primitives);
 
+#if OPENVDB_USE_ORACLE_IN_REBUILD
     auto backToOldGrid = [&xform, &grid](const Coord& coord) -> openvdb::math::Vec3d {
         return grid.transform().worldToIndex(xform->indexToWorld(coord));
     };
@@ -265,14 +278,23 @@ doLevelSetRebuild(const GridType& grid, typename GridType::ValueType iso,
             return value <= 0 ? true : false;
         }
     };
+#endif
 
     if (interrupter) {
         return meshToVolume<GridType>(*interrupter, mesh, *transform, exBandWidth, inBandWidth,
-            DISABLE_RENORMALIZATION, nullptr, interiorTest, EVAL_EVERY_VOXEL);
+            DISABLE_RENORMALIZATION, nullptr
+#if OPENVDB_USE_ORACLE_IN_REBUILD
+            , interiorTest, EVAL_EVERY_VOXEL
+#endif
+            );
     }
 
     return meshToVolume<GridType>(mesh, *transform, exBandWidth, inBandWidth,
-        DISABLE_RENORMALIZATION, nullptr, interiorTest, EVAL_EVERY_VOXEL);
+        DISABLE_RENORMALIZATION, nullptr
+#if OPENVDB_USE_ORACLE_IN_REBUILD
+        , interiorTest, EVAL_EVERY_VOXEL
+#endif
+        );
 }
 
 

openvdb/openvdb/tools/MeshToVolume.h

@@ -4448,14 +4448,14 @@ createLevelSetBox(const math::BBox<VecType>& bbox,
 #define _FUNCTION(TreeT) \
     Grid<TreeT>::Ptr meshToVolume<Grid<TreeT>>(util::NullInterrupter&, \
         const QuadAndTriangleDataAdapter<Vec3s, Vec3I>&, const openvdb::math::Transform&, \
-        float, float, int, Grid<TreeT>::ValueConverter<Int32>::Type*)
+        float, float, int, Grid<TreeT>::ValueConverter<Int32>::Type*, std::nullptr_t, InteriorTestStrategy)
 OPENVDB_REAL_TREE_INSTANTIATE(_FUNCTION)
 #undef _FUNCTION
 
 #define _FUNCTION(TreeT) \
     Grid<TreeT>::Ptr meshToVolume<Grid<TreeT>>(util::NullInterrupter&, \
         const QuadAndTriangleDataAdapter<Vec3s, Vec4I>&, const openvdb::math::Transform&, \
-        float, float, int, Grid<TreeT>::ValueConverter<Int32>::Type*)
+        float, float, int, Grid<TreeT>::ValueConverter<Int32>::Type*, std::nullptr_t, InteriorTestStrategy)
 OPENVDB_REAL_TREE_INSTANTIATE(_FUNCTION)
 #undef _FUNCTION