From 3ba45af59eb7d1abbb1e02b4fd53f16008c9e62e Mon Sep 17 00:00:00 2001
From: Jeongseok Lee <jslee02@users.noreply.github.com>
Date: Mon, 28 Dec 2020 16:53:44 -0800
Subject: [PATCH] Make dart.pc relocatable (#1529)

Co-authored-by: Stefan Profanter <stefan.profanter@agile-robots.com>
---
 CHANGELOG.md     | 1 +
 CMakeLists.txt   | 8 +++++++-
 cmake/dart.pc.in | 6 +++---
 3 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 061030c13d92f..f591a9136b560 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -83,6 +83,7 @@
   * Removed gccfilter: [#1464](https://github.com/dartsim/dart/pull/1464)
   * Allowed to set CMAKE_INSTALL_PREFIX on Windows: [#1478](https://github.com/dartsim/dart/pull/1478)
   * Enforced to use OpenSceneGraph 3.7.0 or greater on macOS Catalina: [#1479](https://github.com/dartsim/dart/pull/1479)
+  * Made `dart.pc` relocatable: [#1529](https://github.com/dartsim/dart/pull/1529)
 
 * Documentation
 
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 12a429ee5f8c4..de2e3e77d3298 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -408,11 +408,17 @@ install(
 # Generate the DART pkg-config
 set(PC_CONFIG_IN ${CMAKE_SOURCE_DIR}/cmake/dart.pc.in)
 set(PC_CONFIG_OUT ${CMAKE_BINARY_DIR}/cmake/dart.pc)
+set(PC_CONFIG_INSTALL_DIR ${CMAKE_INSTALL_PREFIX}/${CMAKE_INSTALL_LIBDIR}/pkgconfig)
+file(RELATIVE_PATH
+  RELATIVE_PATH_TO_INSTALL_PREFIX
+  "${PC_CONFIG_INSTALL_DIR}"
+  "${CMAKE_INSTALL_PREFIX}"
+)
 if(DART_VERBOSE)
   message(STATUS ${PC_CONFIG_OUT})
 endif()
 configure_file(${PC_CONFIG_IN} ${PC_CONFIG_OUT} @ONLY)
-install(FILES ${PC_CONFIG_OUT} DESTINATION ${CMAKE_INSTALL_LIBDIR}/pkgconfig)
+install(FILES ${PC_CONFIG_OUT} DESTINATION ${PC_CONFIG_INSTALL_DIR})
 
 # Install a Catkin 'package.xml' file. This is required by REP-136.
 install(FILES package.xml DESTINATION
diff --git a/cmake/dart.pc.in b/cmake/dart.pc.in
index 90f3cde37ddd8..402c496c42987 100644
--- a/cmake/dart.pc.in
+++ b/cmake/dart.pc.in
@@ -1,8 +1,8 @@
 # This file was generated by CMake for @PROJECT_NAME@
-prefix=@CMAKE_INSTALL_PREFIX@
+prefix=${pcfiledir}/@RELATIVE_PATH_TO_INSTALL_PREFIX@
 exec_prefix=${prefix}
-libdir=${prefix}/lib
-includedir=${prefix}/include/dart
+libdir=${prefix}/@CMAKE_INSTALL_LIBDIR@
+includedir=${prefix}/@CMAKE_INSTALL_INCLUDEDIR@/dart
 
 Name: @PROJECT_NAME@
 Description: @DART_PKG_DESC@