Merge pull request #1304 from OznOg/UseEigen3Config.cmake

CMakeLists.txt

@@ -101,8 +101,6 @@ if(GTSAM_BUILD_PYTHON OR GTSAM_INSTALL_MATLAB_TOOLBOX)
     # Copy matlab.h to the correct folder.
     configure_file(${PROJECT_SOURCE_DIR}/wrap/matlab.h
                ${PROJECT_BINARY_DIR}/wrap/matlab.h COPYONLY)
-    # Add the include directories so that matlab.h can be found
-    include_directories("${PROJECT_BINARY_DIR}" "${GTSAM_EIGEN_INCLUDE_FOR_BUILD}")
 
     add_subdirectory(wrap)
     list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_LIST_DIR}/wrap/cmake")

cmake/Config.cmake.in

@@ -21,6 +21,10 @@ else()
 find_dependency(Boost @BOOST_FIND_MINIMUM_VERSION@ COMPONENTS @BOOST_FIND_MINIMUM_COMPONENTS@)
 endif()
 
+if(@GTSAM_USE_SYSTEM_EIGEN@)
+find_dependency(Eigen3 REQUIRED)
+endif()
+
 # Load exports
 include(${OUR_CMAKE_DIR}/@PACKAGE_NAME@-exports.cmake)
 

cmake/FindEigen3.cmake

@@ -1,81 +0,0 @@
-# - Try to find Eigen3 lib
-#
-# This module supports requiring a minimum version, e.g. you can do
-#   find_package(Eigen3 3.1.2)
-# to require version 3.1.2 or newer of Eigen3.
-#
-# Once done this will define
-#
-#  EIGEN3_FOUND - system has eigen lib with correct version
-#  EIGEN3_INCLUDE_DIR - the eigen include directory
-#  EIGEN3_VERSION - eigen version
-
-# Copyright (c) 2006, 2007 Montel Laurent, <montel@kde.org>
-# Copyright (c) 2008, 2009 Gael Guennebaud, <g.gael@free.fr>
-# Copyright (c) 2009 Benoit Jacob <jacob.benoit.1@gmail.com>
-# Redistribution and use is allowed according to the terms of the 2-clause BSD license.
-
-if(NOT Eigen3_FIND_VERSION)
-  if(NOT Eigen3_FIND_VERSION_MAJOR)
-    set(Eigen3_FIND_VERSION_MAJOR 2)
-  endif(NOT Eigen3_FIND_VERSION_MAJOR)
-  if(NOT Eigen3_FIND_VERSION_MINOR)
-    set(Eigen3_FIND_VERSION_MINOR 91)
-  endif(NOT Eigen3_FIND_VERSION_MINOR)
-  if(NOT Eigen3_FIND_VERSION_PATCH)
-    set(Eigen3_FIND_VERSION_PATCH 0)
-  endif(NOT Eigen3_FIND_VERSION_PATCH)
-
-  set(Eigen3_FIND_VERSION "${Eigen3_FIND_VERSION_MAJOR}.${Eigen3_FIND_VERSION_MINOR}.${Eigen3_FIND_VERSION_PATCH}")
-endif(NOT Eigen3_FIND_VERSION)
-
-macro(_eigen3_check_version)
-  file(READ "${EIGEN3_INCLUDE_DIR}/Eigen/src/Core/util/Macros.h" _eigen3_version_header)
-
-  string(REGEX MATCH "define[ \t]+EIGEN_WORLD_VERSION[ \t]+([0-9]+)" _eigen3_world_version_match "${_eigen3_version_header}")
-  set(EIGEN3_WORLD_VERSION "${CMAKE_MATCH_1}")
-  string(REGEX MATCH "define[ \t]+EIGEN_MAJOR_VERSION[ \t]+([0-9]+)" _eigen3_major_version_match "${_eigen3_version_header}")
-  set(EIGEN3_MAJOR_VERSION "${CMAKE_MATCH_1}")
-  string(REGEX MATCH "define[ \t]+EIGEN_MINOR_VERSION[ \t]+([0-9]+)" _eigen3_minor_version_match "${_eigen3_version_header}")
-  set(EIGEN3_MINOR_VERSION "${CMAKE_MATCH_1}")
-
-  set(EIGEN3_VERSION ${EIGEN3_WORLD_VERSION}.${EIGEN3_MAJOR_VERSION}.${EIGEN3_MINOR_VERSION})
-  if(${EIGEN3_VERSION} VERSION_LESS ${Eigen3_FIND_VERSION})
-    set(EIGEN3_VERSION_OK FALSE)
-  else(${EIGEN3_VERSION} VERSION_LESS ${Eigen3_FIND_VERSION})
-    set(EIGEN3_VERSION_OK TRUE)
-  endif(${EIGEN3_VERSION} VERSION_LESS ${Eigen3_FIND_VERSION})
-
-  if(NOT EIGEN3_VERSION_OK)
-
-    message(STATUS "Eigen3 version ${EIGEN3_VERSION} found in ${EIGEN3_INCLUDE_DIR}, "
-                   "but at least version ${Eigen3_FIND_VERSION} is required")
-  endif(NOT EIGEN3_VERSION_OK)
-endmacro(_eigen3_check_version)
-
-if (EIGEN3_INCLUDE_DIR)
-
-  # in cache already
-  _eigen3_check_version()
-  set(EIGEN3_FOUND ${EIGEN3_VERSION_OK})
-
-else (EIGEN3_INCLUDE_DIR)
-
-  find_path(EIGEN3_INCLUDE_DIR NAMES signature_of_eigen3_matrix_library
-      PATHS
-      ${CMAKE_INSTALL_PREFIX}/include
-      ${KDE4_INCLUDE_DIR}
-      PATH_SUFFIXES eigen3 eigen
-    )
-
-  if(EIGEN3_INCLUDE_DIR)
-    _eigen3_check_version()
-  endif(EIGEN3_INCLUDE_DIR)
-
-  include(FindPackageHandleStandardArgs)
-  find_package_handle_standard_args(Eigen3 DEFAULT_MSG EIGEN3_INCLUDE_DIR EIGEN3_VERSION_OK)
-
-  mark_as_advanced(EIGEN3_INCLUDE_DIR)
-
-endif(EIGEN3_INCLUDE_DIR)
-

cmake/HandleEigen.cmake

@@ -1,7 +1,7 @@
 ###############################################################################
 # Option for using system Eigen or GTSAM-bundled Eigen
 # Default: Use system's Eigen if found automatically:
-find_package(Eigen3 QUIET)
+find_package(Eigen3 CONFIG QUIET)
 set(USE_SYSTEM_EIGEN_INITIAL_VALUE ${Eigen3_FOUND})
 option(GTSAM_USE_SYSTEM_EIGEN "Find and use system-installed Eigen. If 'off', use the one bundled with GTSAM" ${USE_SYSTEM_EIGEN_INITIAL_VALUE})
 unset(USE_SYSTEM_EIGEN_INITIAL_VALUE)
@@ -14,10 +14,14 @@ endif()
 
 # Switch for using system Eigen or GTSAM-bundled Eigen
 if(GTSAM_USE_SYSTEM_EIGEN)
-    find_package(Eigen3 REQUIRED) # need to find again as REQUIRED
+    # Since Eigen 3.3.0 a Eigen3Config.cmake is available so use it.
+    find_package(Eigen3 CONFIG REQUIRED) # need to find again as REQUIRED
 
-    # Use generic Eigen include paths e.g. <Eigen/Core>
+    # The actual include directory (for BUILD cmake target interface):
-    set(GTSAM_EIGEN_INCLUDE_FOR_INSTALL "${EIGEN3_INCLUDE_DIR}")
+    # Note: EIGEN3_INCLUDE_DIR points to some random location on some eigen
+    # versions.  So here I use the target itself to get the proper include
+    # directory (it is generated by cmake, thus has the correct path)
+    get_target_property(GTSAM_EIGEN_INCLUDE_FOR_BUILD Eigen3::Eigen INTERFACE_INCLUDE_DIRECTORIES)
 
     # check if MKL is also enabled - can have one or the other, but not both!
     # Note: Eigen >= v3.2.5 includes our patches
@@ -30,9 +34,6 @@ if(GTSAM_USE_SYSTEM_EIGEN)
     if(EIGEN_USE_MKL_ALL AND (EIGEN3_VERSION VERSION_EQUAL 3.3.4))
         message(FATAL_ERROR "MKL does not work with Eigen 3.3.4 because of a bug in Eigen. See http://eigen.tuxfamily.org/bz/show_bug.cgi?id=1527. Disable GTSAM_USE_SYSTEM_EIGEN to use GTSAM's copy of Eigen, disable GTSAM_WITH_EIGEN_MKL, or upgrade/patch your installation of Eigen.")
     endif()
-
-    # The actual include directory (for BUILD cmake target interface):
-    set(GTSAM_EIGEN_INCLUDE_FOR_BUILD "${EIGEN3_INCLUDE_DIR}")
 else()
     # Use bundled Eigen include path.
     # Clear any variables set by FindEigen3
@@ -46,6 +47,19 @@ else()
 
     # The actual include directory (for BUILD cmake target interface):
     set(GTSAM_EIGEN_INCLUDE_FOR_BUILD "${GTSAM_SOURCE_DIR}/gtsam/3rdparty/Eigen/")
+
+    add_library(gtsam_eigen3 INTERFACE)
+
+    target_include_directories(gtsam_eigen3 INTERFACE
+      $<BUILD_INTERFACE:${GTSAM_EIGEN_INCLUDE_FOR_BUILD}>
+      $<INSTALL_INTERFACE:${GTSAM_EIGEN_INCLUDE_FOR_INSTALL}>
+    )
+    add_library(Eigen3::Eigen ALIAS gtsam_eigen3)
+
+    install(TARGETS gtsam_eigen3 EXPORT GTSAM-exports PUBLIC_HEADER DESTINATION ${CMAKE_INSTALL_INCLUDEDIR})
+
+    list(APPEND GTSAM_EXPORTED_TARGETS gtsam_eigen3)
+    set(GTSAM_EXPORTED_TARGETS "${GTSAM_EXPORTED_TARGETS}" PARENT_SCOPE)
 endif()
 
 # Detect Eigen version:

gtsam/CMakeLists.txt

@@ -117,12 +117,9 @@ set_target_properties(gtsam PROPERTIES
     VERSION             ${gtsam_version}
     SOVERSION           ${gtsam_soversion})
 
-# Append Eigen include path, set in top-level CMakeLists.txt to either
 # system-eigen, or GTSAM eigen path
-target_include_directories(gtsam PUBLIC
+target_link_libraries(gtsam PUBLIC Eigen3::Eigen)
-  $<BUILD_INTERFACE:${GTSAM_EIGEN_INCLUDE_FOR_BUILD}>
+
-  $<INSTALL_INTERFACE:${GTSAM_EIGEN_INCLUDE_FOR_INSTALL}>
-)
 # MKL include dir:
 if (GTSAM_USE_EIGEN_MKL)
   target_include_directories(gtsam PUBLIC ${MKL_INCLUDE_DIR})