I’ve been struggling with a seemingly simple problem. My CMakeLists.txt looks for a package named “Proj”, with find_package() and third-party-provided FindProj.cmake, but is unable to find it on MacOS when the package has been installed with MacPorts. In this case MacPorts installs the Proj headers/libraries into directory /opt/local/lib/proj*, where ‘*’ is a digit indicating the Proj version; e.g. my system has two Proj versions installed:
% ls -d /opt/local/lib/proj*
/opt/local/lib/proj6 /opt/local/lib/proj8
Neither proj6 nor proj8 provides proj_config.cmake or ProjConfig.cmake, although newer Proj versions do. I always want to find the newest installed Proj version, so I assume
I should call find_package() such that it first tries the Config approach, followed by the Module approach - something like this:
find_package(PROJ)
But cmake is unable to find either /opt/local/lib/proj6 or /opt/local/proj8. I do have a third-party FindProj.cmake script installed but I confess I don’t really understand how it works. Can I somehow provide a “hint” to this script, e.g. tell it to look under “/opt/local/lib”? FindProj.cmake looks like this:
# Find Proj
# ~~~~~~~~~
# Copyright (c) 2007, Martin Dobias <wonder.sk at gmail.com>
# Redistribution and use is allowed according to the terms of the BSD license.
# For details see the accompanying COPYING-CMAKE-SCRIPTS file.
#
# CMake module to search for Proj library
#
# If it's found it sets PROJ_FOUND to TRUE
# and following variables are set:
# PROJ_INCLUDE_DIR
# PROJ_LIBRARY
# FIND_PATH and FIND_LIBRARY normally search standard locations
# before the specified paths. To search non-standard paths first,
# FIND_* is invoked first with specified paths and NO_DEFAULT_PATH
# and then again with no specified paths to search the default
# locations. When an earlier FIND_* succeeds, subsequent FIND_*s
# searching for the same item do nothing.
# try to use framework on mac
# want clean framework path, not unix compatibility path
message("In FindProj() module!")
IF (APPLE)
IF (CMAKE_FIND_FRAMEWORK MATCHES "FIRST"
OR CMAKE_FRAMEWORK_PATH MATCHES "ONLY"
OR NOT CMAKE_FIND_FRAMEWORK)
SET (CMAKE_FIND_FRAMEWORK_save ${CMAKE_FIND_FRAMEWORK} CACHE STRING "" FORCE)
SET (CMAKE_FIND_FRAMEWORK "ONLY" CACHE STRING "" FORCE)
#FIND_PATH(PROJ_INCLUDE_DIR PROJ/proj.h)
FIND_LIBRARY(PROJ_LIBRARY PROJ)
IF (PROJ_LIBRARY)
# FIND_PATH doesn't add "Headers" for a framework
SET (PROJ_INCLUDE_DIR ${PROJ_LIBRARY}/Headers CACHE PATH "Path to a file.")
ENDIF (PROJ_LIBRARY)
SET (CMAKE_FIND_FRAMEWORK ${CMAKE_FIND_FRAMEWORK_save} CACHE STRING "" FORCE)
ENDIF ()
ENDIF (APPLE)
FIND_PATH(PROJ_INCLUDE_DIR proj.h
"$ENV{INCLUDE}"
"$ENV{LIB_DIR}/include"
)
FIND_LIBRARY(PROJ_LIBRARY NAMES proj_i proj PATHS
"$ENV{LIB}"
"$ENV{LIB_DIR}/lib"
)
IF (PROJ_INCLUDE_DIR AND PROJ_LIBRARY)
SET(PROJ_FOUND TRUE)
ENDIF (PROJ_INCLUDE_DIR AND PROJ_LIBRARY)
IF (PROJ_FOUND)
IF (EXISTS ${PROJ_INCLUDE_DIR}/proj.h AND EXISTS ${PROJ_INCLUDE_DIR}/proj_experimental.h)
FILE(READ ${PROJ_INCLUDE_DIR}/proj.h proj_version)
STRING(REGEX REPLACE "^.*PROJ_VERSION_MAJOR +([0-9]+).*$" "\\1" PROJ_VERSION_MAJOR "${proj_version}")
STRING(REGEX REPLACE "^.*PROJ_VERSION_MINOR +([0-9]+).*$" "\\1" PROJ_VERSION_MINOR "${proj_version}")
STRING(REGEX REPLACE "^.*PROJ_VERSION_PATCH +([0-9]+).*$" "\\1" PROJ_VERSION_PATCH "${proj_version}")
STRING(CONCAT PROJ_VERSION_STR "(" ${PROJ_VERSION_MAJOR} "." ${PROJ_VERSION_MINOR} "." ${PROJ_VERSION_PATCH} ")")
IF ((PROJ_VERSION_MAJOR EQUAL 6) AND ((PROJ_VERSION_MINOR LESS 3) OR (PROJ_VERSION_MINOR EQUAL 3 AND PROJ_VERSION_PATCH LESS 1)))
MESSAGE (FATAL_ERROR "Cannot build QGIS using Proj ${PROJ_VERSION_MAJOR}.${PROJ_VERSION_MINOR}.${PROJ_VERSION_PATCH} Use 6.3.1 or higher.")
ENDIF ((PROJ_VERSION_MAJOR EQUAL 6) AND ((PROJ_VERSION_MINOR LESS 3) OR (PROJ_VERSION_MINOR EQUAL 3 AND PROJ_VERSION_PATCH LESS 1)))
ELSE(EXISTS ${PROJ_INCLUDE_DIR}/proj.h AND EXISTS ${PROJ_INCLUDE_DIR}/proj_experimental.h)
FILE(READ ${PROJ_INCLUDE_DIR}/proj.h proj_version)
STRING(REGEX REPLACE "^.*PJ_VERSION ([0-9]+).*$" "\\1" PJ_VERSION "${proj_version}")
# This will break if 4.10.0 ever will be released (highly unlikely)
STRING(REGEX REPLACE "([0-9])([0-9])([0-9])" "\\1" PROJ_VERSION_MAJOR "${PJ_VERSION}")
STRING(REGEX REPLACE "([0-9])([0-9])([0-9])" "\\2" PROJ_VERSION_MINOR "${PJ_VERSION}")
STRING(REGEX REPLACE "([0-9])([0-9])([0-9])" "\\3" PROJ_VERSION_PATCH "${PJ_VERSION}")
STRING(CONCAT PROJ_VERSION_STR "(" ${PROJ_VERSION_MAJOR} "." ${PROJ_VERSION_MINOR} "." ${PROJ_VERSION_PATCH} ")")
# Minimum Proj version required is 4.9.3
IF ((PROJ_VERSION_MAJOR EQUAL 4) AND ((PROJ_VERSION_MINOR LESS 9) OR ((PROJ_VERSION_MINOR EQUAL 9) AND (PROJ_VERSION_PATCH LESS 3))))
MESSAGE(FATAL_ERROR "Found Proj: ${PROJ_VERSION_MAJOR}.${PROJ_VERSION_MINOR}.${PROJ_VERSION_PATCH}. Cannot build QGIS using Proj older than 4.9.3.")
ENDIF((PROJ_VERSION_MAJOR EQUAL 4) AND ((PROJ_VERSION_MINOR LESS 9) OR ((PROJ_VERSION_MINOR EQUAL 9) AND (PROJ_VERSION_PATCH LESS 3))))
ENDIF(EXISTS ${PROJ_INCLUDE_DIR}/proj.h AND EXISTS ${PROJ_INCLUDE_DIR}/proj_experimental.h)
IF (NOT PROJ_FIND_QUIETLY)
MESSAGE(STATUS "Found Proj: ${PROJ_LIBRARY} version ${PROJ_VERSION_MAJOR} ${PROJ_VERSION_STR}")
ENDIF (NOT PROJ_FIND_QUIETLY)
INCLUDE_DIRECTORIES(SYSTEM BEFORE ${PROJ_INCLUDE_DIR})
ADD_DEFINITIONS(-DPROJ_VERSION_MAJOR=${PROJ_VERSION_MAJOR})
ELSE (PROJ_FOUND)
IF (PROJ_FIND_REQUIRED)
MESSAGE(FATAL_ERROR "Could not find Proj")
ENDIF (PROJ_FIND_REQUIRED)
ENDIF (PROJ_FOUND)