Replace boost conversion_traits with std::common_type

cmake/FindOpenVDB.cmake

@@ -491,37 +491,11 @@ endif()
 # Add standard dependencies
 
 find_package(TBB REQUIRED COMPONENTS tbb)
-find_package(Boost REQUIRED COMPONENTS iostreams)
 
 # Add deps for pyopenvdb
-# @todo track for numpy
 
 if(pyopenvdb IN_LIST OpenVDB_FIND_COMPONENTS)
   find_package(Python REQUIRED)
-
-  # Boost python handling - try and find both python and pythonXx (version suffixed).
-  # Prioritize the version suffixed library, failing if neither exist.
-
-  find_package(Boost ${MINIMUM_BOOST_VERSION}
-    QUIET COMPONENTS python${PYTHON_VERSION_MAJOR}${PYTHON_VERSION_MINOR}
-  )
-
-  if(TARGET Boost::python${PYTHON_VERSION_MAJOR}${PYTHON_VERSION_MINOR})
-    set(BOOST_PYTHON_LIB "python${PYTHON_VERSION_MAJOR}${PYTHON_VERSION_MINOR}")
-    message(STATUS "Found boost_python${PYTHON_VERSION_MAJOR}${PYTHON_VERSION_MINOR}")
-  else()
-    find_package(Boost ${MINIMUM_BOOST_VERSION} QUIET COMPONENTS python)
-    if(TARGET Boost::python)
-      set(BOOST_PYTHON_LIB "python")
-      message(STATUS "Found non-suffixed boost_python, assuming to be python version "
-        "\"${PYTHON_VERSION_MAJOR}.${PYTHON_VERSION_MINOR}\" compatible"
-      )
-    else()
-      message(FATAL_ERROR "Unable to find boost_python or "
-        "boost_python${PYTHON_VERSION_MAJOR}${PYTHON_VERSION_MINOR}."
-      )
-    endif()
-  endif()
 endif()
 
 # Add deps for openvdb_ax
@@ -656,6 +630,10 @@ if(OpenVDB_USES_IMATH_HALF)
   find_package(Imath REQUIRED CONFIG)
 endif()
 
+if(OpenVDB_USES_DELAYED_LOADING)
+  find_package(Boost REQUIRED COMPONENTS iostreams)
+endif()
+
 if(UNIX)
   find_package(Threads REQUIRED)
 endif()
@@ -766,7 +744,7 @@ if(OpenVDB_pyopenvdb_LIBRARY)
     set_target_properties(OpenVDB::pyopenvdb PROPERTIES
       IMPORTED_LOCATION "${OpenVDB_pyopenvdb_LIBRARY}"
       INTERFACE_INCLUDE_DIRECTORIES "${OpenVDB_pyopenvdb_INCLUDE_DIR};${PYTHON_INCLUDE_DIR}"
-      INTERFACE_LINK_LIBRARIES "OpenVDB::openvdb;Boost::${BOOST_PYTHON_LIB};${PYTHON_LIBRARIES}"
+      INTERFACE_LINK_LIBRARIES "OpenVDB::openvdb;${PYTHON_LIBRARIES}"
       INTERFACE_COMPILE_FEATURES cxx_std_17
    )
   endif()

doc/build.txt

@@ -267,7 +267,7 @@ PyBind11       | C++/python bindings
 NumPy          | Scientific computing with Python                                | Optional (Python)  |
 LLVM           | Target-independent code generation                              | OpenVDB AX         |
 
-At a minimum, boost, a matching C++17 compiler and CMake will be required. See
+At a minimum a matching C++17 compiler and CMake will be required. See
 the full [dependency list](@ref dependencies) for help with downloading and
 installing the above software. Note that as Blosc and ZLib are provided as part
 of the Houdini installation `USE_BLOSC` and `USE_ZLIB` should be left `ON`.

doc/dependencies.txt

@@ -36,7 +36,7 @@ Reference Platform, but for those that do, their specified versions are
 
 Component               | Requirements                                    | Optional
 ----------------------- | ----------------------------------------------- | --------
-OpenVDB Core Library    | CMake, C++17 compiler, TBB::tbb, Boost::headers | Blosc, ZLib, Log4cplus, Imath::Imath, Boost::iostream
+OpenVDB Core Library    | CMake, C++17 compiler, TBB::tbb                 | Blosc, ZLib, Log4cplus, Imath::Imath, Boost::iostream
 OpenVDB Print           | Core Library dependencies                       | -
 OpenVDB LOD             | Core Library dependencies                       | -
 OpenVDB Render          | Core Library dependencies                       | OpenEXR, Imath::Imath, libpng
@@ -65,7 +65,7 @@ Imath          | 3.1     | Latest      | Half precision floating points
 OpenEXR        | 3.1     | Latest      | EXR serialization support                                         | Y       | Y        | http://www.openexr.com
 TBB            | 2020.2  | 2020.3      | Threading Building Blocks - template library for task parallelism | Y       | Y        | https://www.threadingbuildingblocks.org
 ZLIB           | 1.2.7   | Latest      | Compression library for disk serialization compression            | Y       | Y        | https://www.zlib.net
-Boost          | 1.73    | 1.80        | Components: headers, iostreams                                    | Y       | Y        | https://www.boost.org
+Boost          | 1.73    | 1.80        | Components: iostreams                                             | Y       | Y        | https://www.boost.org
 LLVM           | 10.0.0  | 13.0.0*     | Target-independent code generation                                | Y       | Y        | https://llvm.org/
 Bison          | 3.0.0   | 3.7.0       | General-purpose parser generator                                  | Y       | Y        | https://www.gnu.org/software/gcc
 Flex           | 2.6.0   | 2.6.4       | Fast lexical analyzer generator                                   | Y       | Y        | https://github.com/westes/flex

openvdb/openvdb/CMakeLists.txt

@@ -110,16 +110,14 @@ endif()
 
 if(OPENVDB_USE_DELAYED_LOADING)
   find_package(Boost ${MINIMUM_BOOST_VERSION} REQUIRED COMPONENTS iostreams)
-else()
-  find_package(Boost ${MINIMUM_BOOST_VERSION} REQUIRED COMPONENTS headers)
-endif()
 
-if(OPENVDB_FUTURE_DEPRECATION AND FUTURE_MINIMUM_BOOST_VERSION)
-  # The X.Y.Z boost version value isn't available until CMake 3.14
-  set(FULL_BOOST_VERSION "${Boost_MAJOR_VERSION}.${Boost_MINOR_VERSION}.${Boost_SUBMINOR_VERSION}")
-  if(${FULL_BOOST_VERSION} VERSION_LESS FUTURE_MINIMUM_BOOST_VERSION)
-    message(DEPRECATION "Support for Boost versions < ${FUTURE_MINIMUM_BOOST_VERSION} "
-      "is deprecated and will be removed.")
+  if(OPENVDB_FUTURE_DEPRECATION AND FUTURE_MINIMUM_BOOST_VERSION)
+    # The X.Y.Z boost version value isn't available until CMake 3.14
+    set(FULL_BOOST_VERSION "${Boost_MAJOR_VERSION}.${Boost_MINOR_VERSION}.${Boost_SUBMINOR_VERSION}")
+    if(${FULL_BOOST_VERSION} VERSION_LESS FUTURE_MINIMUM_BOOST_VERSION)
+      message(DEPRECATION "Support for Boost versions < ${FUTURE_MINIMUM_BOOST_VERSION} "
+        "is deprecated and will be removed.")
+    endif()
   endif()
 endif()
 
@@ -246,20 +244,17 @@ endif()
 
 if(OPENVDB_USE_DELAYED_LOADING)
   list(APPEND OPENVDB_CORE_DEPENDENT_LIBS Boost::iostreams)
-else()
-  list(APPEND OPENVDB_CORE_DEPENDENT_LIBS Boost::headers)
-endif()
-
-if(WIN32)
-  # Boost headers contain #pragma commands on Windows which causes Boost
-  # libraries to be linked in automatically. Custom boost installations
-  # may find that these naming conventions don't always match and can
-  # cause linker errors. This option disables this feature of Boost. Note
-  # -DBOOST_ALL_NO_LIB can also be provided manually.
-  if(OPENVDB_DISABLE_BOOST_IMPLICIT_LINKING)
-      list(APPEND OPENVDB_CORE_DEPENDENT_LIBS
-        Boost::disable_autolinking  # add -DBOOST_ALL_NO_LIB
-      )
+  if(WIN32)
+    # Boost headers contain #pragma commands on Windows which causes Boost
+    # libraries to be linked in automatically. Custom boost installations
+    # may find that these naming conventions don't always match and can
+    # cause linker errors. This option disables this feature of Boost. Note
+    # -DBOOST_ALL_NO_LIB can also be provided manually.
+    if(OPENVDB_DISABLE_BOOST_IMPLICIT_LINKING)
+        list(APPEND OPENVDB_CORE_DEPENDENT_LIBS
+          Boost::disable_autolinking  # add -DBOOST_ALL_NO_LIB
+        )
+    endif()
   endif()
 endif()
 

openvdb/openvdb/math/Math.h

@@ -11,7 +11,6 @@
 #include <openvdb/Platform.h>
 #include <openvdb/version.h>
 #include <openvdb/util/Assert.h>
-#include <boost/numeric/conversion/conversion_traits.hpp>
 #include <algorithm> // for std::max()
 #include <cassert>
 #include <cmath>     // for std::ceil(), std::fabs(), std::pow(), std::sqrt(), etc.
@@ -917,10 +916,9 @@ enum RotationOrder {
     ZXZ_ROTATION
 };
 
-
-template <typename S, typename T>
+template <typename S, typename T, typename = std::enable_if_t<std::is_arithmetic_v<S>&& std::is_arithmetic_v<T>>>
 struct promote {
-    using type = typename boost::numeric::conversion_traits<S, T>::supertype;
+    using type = typename std::common_type_t<S,T>;
 };
 
 /// @brief Return the index [0,1,2] of the smallest value in a 3D vector.

pendingchanges/boost_promote.txt

@@ -0,0 +1,4 @@
+OpenVDB:
+    Improvements:
+        - Removed last traces of Boost when OPENVDB_USE_DELAYED_LOADING is OFF
+        [Reported by Brian McKinnon]