Merge branch 'static-build' into 'master'

Optional local source builds of OSG, MyGUI, Bullet

See merge request OpenMW/openmw!547

.gitignore

@@ -5,7 +5,7 @@ CMakeCache.txt
 cmake_install.cmake
 Makefile
 makefile
-build*
+build*/
 prebuilt
 
 ##windows build process

.gitlab-ci.yml

@@ -1,19 +1,20 @@
+# Note: We set `needs` on each job to control the job DAG.
+# See https://docs.gitlab.com/ee/ci/yaml/#needs
 stages:
   - build
 
-.Debian:
+.Debian_Image:
   tags:
     - docker
     - linux
   image: debian:bullseye
+
+.Debian:
+  extends: .Debian_Image
   cache:
     paths:
     - apt-cache/
     - ccache/
-  before_script:
-    - export APT_CACHE_DIR=`pwd`/apt-cache && mkdir -pv $APT_CACHE_DIR
-    - apt-get update -yq 
-    - apt-get -o dir::cache::archives="$APT_CACHE_DIR" install -y cmake build-essential libboost-filesystem-dev libboost-program-options-dev libboost-system-dev libboost-iostreams-dev libavcodec-dev libavformat-dev libavutil-dev libswscale-dev libswresample-dev libsdl2-dev libqt5opengl5-dev libopenal-dev libopenscenegraph-dev libunshield-dev libtinyxml-dev libmygui-dev libbullet-dev liblz4-dev ccache git clang
   stage: build
   script:
     - export CCACHE_BASEDIR="`pwd`"
@@ -33,6 +34,8 @@ Debian_GCC:
   extends: .Debian
   cache:
     key: Debian_GCC.v2
+  before_script:
+    - CI/install_debian_deps.sh gcc openmw-deps openmw-deps-dynamic
   variables:
     CC: gcc
     CXX: g++
@@ -41,31 +44,52 @@ Debian_GCC:
   timeout: 2h
 
 Debian_GCC_tests:
-  extends: .Debian
+  extends: Debian_GCC
   cache:
     key: Debian_GCC_tests.v2
   variables:
-    CC: gcc
+    CCACHE_SIZE: 1G
-    CXX: g++
+    BUILD_TESTS_ONLY: 1
+
+Debian_GCC_Static_Deps:
+  extends: Debian_GCC
+  cache:
+    key: Debian_GCC_Static_Deps
+    paths:
+    - apt-cache/
+    - ccache/
+    - build/extern/fetched/
+  before_script:
+    - CI/install_debian_deps.sh gcc openmw-deps openmw-deps-static
+  variables:
+    CI_OPENMW_USE_STATIC_DEPS: 1
+
+Debian_GCC_Static_Deps_tests:
+  extends: Debian_GCC_Static_Deps
+  cache:
+    key: Debian_GCC_Static_Deps_tests
+  variables:
     CCACHE_SIZE: 1G
     BUILD_TESTS_ONLY: 1
 
 Debian_Clang:
   extends: .Debian
+  before_script:
+    - CI/install_debian_deps.sh clang openmw-deps openmw-deps-dynamic
   cache:
     key: Debian_Clang.v2
   variables:
     CC: clang
     CXX: clang++
     CCACHE_SIZE: 2G
+  # When CCache doesn't exist (e.g. first build on a fork), build takes more than 1h, which is the default for forks.
+  timeout: 2h
 
 Debian_Clang_tests:
-  extends: .Debian
+  extends: Debian_Clang
   cache:
     key: Debian_Clang_tests.v2
   variables:
-    CC: clang
-    CXX: clang++
     CCACHE_SIZE: 1G
     BUILD_TESTS_ONLY: 1
 
@@ -286,16 +310,17 @@ Debian_AndroidNDK_arm64-v8a:
   variables:
     CCACHE_SIZE: 3G
   cache:
-    key: Debian_AndroidNDK_arm64-v8a.v2
+    key: Debian_AndroidNDK_arm64-v8a.v3
     paths:
       - apt-cache/
       - ccache/
+      - build/extern/fetched/
   before_script:
     - export APT_CACHE_DIR=`pwd`/apt-cache && mkdir -pv $APT_CACHE_DIR
     - echo "deb http://deb.debian.org/debian unstable main contrib" > /etc/apt/sources.list
     - echo "google-android-ndk-installer google-android-installers/mirror select https://dl.google.com" | debconf-set-selections
     - apt-get update -yq
-    - apt-get -o dir::cache::archives="$APT_CACHE_DIR" install -y cmake ccache curl unzip git build-essential google-android-ndk-installer
+    - apt-get -q -o dir::cache::archives="$APT_CACHE_DIR" install -y cmake ccache curl unzip git build-essential google-android-ndk-installer
   stage: build
   script:
     - export CCACHE_BASEDIR="`pwd`"
@@ -310,3 +335,5 @@ Debian_AndroidNDK_arm64-v8a:
   artifacts:
     paths:
       - build/install/
+  # When CCache doesn't exist (e.g. first build on a fork), build takes more than 1h, which is the default for forks.
+  timeout: 1h30m

CI/before_script.android.sh

@@ -3,7 +3,7 @@
 # hack to work around: FFmpeg version is too old, 3.2 is required
 sed -i s/"NOT FFVER_OK"/"FALSE"/ CMakeLists.txt
 
-mkdir build
+mkdir -p build
 cd build
 
 cmake \
@@ -21,5 +21,7 @@ cmake \
 -DBUILD_ESSIMPORTER=0 \
 -DBUILD_OPENCS=0 \
 -DBUILD_WIZARD=0 \
--DMyGUI_LIBRARY="/usr/lib/android-sdk/ndk-bundle/toolchains/llvm/prebuilt/linux-x86_64/sysroot/usr/lib/libMyGUIEngineStatic.a" \
+-DOPENMW_USE_SYSTEM_MYGUI=OFF \
+-DOPENMW_USE_SYSTEM_OSG=OFF \
+-DOPENMW_USE_SYSTEM_BULLET=OFF \
 ..

CI/before_script.linux.sh

@@ -1,44 +1,54 @@
-#!/bin/bash -ex
+#!/bin/bash
+
+set -xeo pipefail
 
 free -m
 
 if [[ "${BUILD_TESTS_ONLY}" ]]; then
-    export GOOGLETEST_DIR="$(pwd)/googletest/build/install"
+    export GOOGLETEST_DIR="${PWD}/googletest/build/install"
     env GENERATOR='Unix Makefiles' CONFIGURATION=Release CI/build_googletest.sh
 fi
 
-mkdir build
+declare -a CMAKE_CONF_OPTS=(
+    -DCMAKE_C_COMPILER="${CC:-/usr/bin/cc}"
+    -DCMAKE_CXX_COMPILER="${CXX:-/usr/bin/c++}"
+    -DCMAKE_C_COMPILER_LAUNCHER=ccache
+    -DCMAKE_CXX_COMPILER_LAUNCHER=ccache
+    -DCMAKE_INSTALL_PREFIX=install
+    -DCMAKE_BUILD_TYPE=RelWithDebInfo
+    -DBUILD_SHARED_LIBS=OFF
+    -DUSE_SYSTEM_TINYXML=ON
+    -DCMAKE_INSTALL_PREFIX=install
+)
+
+if [[ $CI_OPENMW_USE_STATIC_DEPS ]]; then
+    CMAKE_CONF_OPTS+=(
+        -DOPENMW_USE_SYSTEM_MYGUI=OFF
+        -DOPENMW_USE_SYSTEM_OSG=OFF
+        -DOPENMW_USE_SYSTEM_BULLET=OFF
+    )
+fi
+
+mkdir -p build
 cd build
 
 if [[ "${BUILD_TESTS_ONLY}" ]]; then
     ${ANALYZE} cmake \
-        -D CMAKE_C_COMPILER="${CC}" \
+        "${CMAKE_CONF_OPTS[@]}" \
-        -D CMAKE_CXX_COMPILER="${CXX}" \
+        -DBUILD_OPENMW=OFF \
-        -D CMAKE_C_COMPILER_LAUNCHER=ccache \
+        -DBUILD_BSATOOL=OFF \
-        -D CMAKE_CXX_COMPILER_LAUNCHER=ccache \
+        -DBUILD_ESMTOOL=OFF \
-        -D CMAKE_INSTALL_PREFIX=install \
+        -DBUILD_LAUNCHER=OFF \
-        -D CMAKE_BUILD_TYPE=RelWithDebInfo \
+        -DBUILD_MWINIIMPORTER=OFF \
-        -D USE_SYSTEM_TINYXML=TRUE \
+        -DBUILD_ESSIMPORTER=OFF \
-        -D BUILD_OPENMW=OFF \
+        -DBUILD_OPENCS=OFF \
-        -D BUILD_BSATOOL=OFF \
+        -DBUILD_WIZARD=OFF \
-        -D BUILD_ESMTOOL=OFF \
+        -DBUILD_UNITTESTS=ON \
-        -D BUILD_LAUNCHER=OFF \
+        -DGTEST_ROOT="${GOOGLETEST_DIR}" \
-        -D BUILD_MWINIIMPORTER=OFF \
+        -DGMOCK_ROOT="${GOOGLETEST_DIR}" \
-        -D BUILD_ESSIMPORTER=OFF \
-        -D BUILD_OPENCS=OFF \
-        -D BUILD_WIZARD=OFF \
-        -D BUILD_UNITTESTS=ON \
-        -D GTEST_ROOT="${GOOGLETEST_DIR}" \
-        -D GMOCK_ROOT="${GOOGLETEST_DIR}" \
         ..
 else
     ${ANALYZE} cmake \
-        -D CMAKE_C_COMPILER="${CC}" \
+        "${CMAKE_CONF_OPTS[@]}" \
-        -D CMAKE_CXX_COMPILER="${CXX}" \
-        -D CMAKE_C_COMPILER_LAUNCHER=ccache \
-        -D CMAKE_CXX_COMPILER_LAUNCHER=ccache \
-        -D USE_SYSTEM_TINYXML=TRUE \
-        -D CMAKE_INSTALL_PREFIX=install \
-        -D CMAKE_BUILD_TYPE=Debug \
         ..
 fi

CI/install_debian_deps.sh

@@ -0,0 +1,64 @@
+#!/bin/bash
+
+set -euo pipefail
+
+print_help() {
+  echo "usage: $0 [group]..."
+  echo
+  echo "  available groups: "${!GROUPED_DEPS[@]}""
+}
+
+declare -rA GROUPED_DEPS=(
+  [gcc]="binutils gcc g++ libc-dev"
+  [clang]="binutils clang"
+
+  # Common dependencies for building OpenMW.
+  [openmw-deps]="
+    make cmake ccache git pkg-config
+
+    libboost-filesystem-dev libboost-program-options-dev
+    libboost-system-dev libboost-iostreams-dev
+    
+    libavcodec-dev libavformat-dev libavutil-dev libswscale-dev libswresample-dev
+    libsdl2-dev libqt5opengl5-dev libopenal-dev libunshield-dev libtinyxml-dev
+    libbullet-dev liblz4-dev libpng-dev libjpeg-dev
+  "
+
+  # These dependencies can alternatively be built and linked statically.
+  [openmw-deps-dynamic]="libmygui-dev libopenscenegraph-dev"
+
+  # Pre-requisites for building MyGUI and OSG for static linking.
+  #
+  # * MyGUI and OSG: libsdl2-dev liblz4-dev libfreetype6-dev
+  # * OSG: libgl-dev
+  #
+  #   Plugins:
+  #   * DAE: libcollada-dom-dev libboost-system-dev libboost-filesystem-dev
+  #   * JPEG: libjpeg-dev
+  #   * PNG: libpng-dev
+  [openmw-deps-static]="
+    make cmake
+    ccache curl unzip libcollada-dom-dev libfreetype6-dev libjpeg-dev libpng-dev
+    libsdl2-dev libboost-system-dev libboost-filesystem-dev libgl-dev
+  "
+)
+
+if [[ $# -eq 0 ]]; then
+  >&2 print_help
+  exit 1
+fi
+
+deps=()
+for group in "$@"; do
+  if [[ ! -v GROUPED_DEPS[$group] ]]; then
+    >&2 echo "error: unknown group ${group}"
+    exit 1
+  fi
+  deps+=(${GROUPED_DEPS[$group]})
+done
+
+export APT_CACHE_DIR="${PWD}/apt-cache"
+set -x
+mkdir -pv "$APT_CACHE_DIR"
+apt-get update -yq
+apt-get -q -o dir::cache::archives="$APT_CACHE_DIR" install -y "${deps[@]}"

CMakeLists.txt

@@ -3,14 +3,19 @@ cmake_minimum_required(VERSION 3.1.0)
 set(CMAKE_CXX_STANDARD 17)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 
-# Detect OS
-include(cmake/OSIdentity.cmake)
-
 # for link time optimization, remove if cmake version is >= 3.9
-if(POLICY CMP0069)
+if(POLICY CMP0069) # LTO
   cmake_policy(SET CMP0069 NEW)
 endif()
 
+# for position-independent executable, remove if cmake version is >= 3.14
+if(POLICY CMP0083)
+  cmake_policy(SET CMP0083 NEW)
+endif()
+
+# Detect OS
+include(cmake/OSIdentity.cmake)
+
 # Apps and tools
 option(BUILD_OPENMW             "Build OpenMW" ON)
 option(BUILD_LAUNCHER           "Build Launcher" ON)
@@ -52,7 +57,6 @@ set(CMAKE_MODULE_PATH ${CMAKE_SOURCE_DIR}/cmake/)
 
 if (ANDROID)
     set(CMAKE_FIND_ROOT_PATH ${OPENMW_DEPENDENCIES_DIR} "${CMAKE_FIND_ROOT_PATH}")
-    set (OSG_PLUGINS_DIR CACHE STRING "")
 endif()
 
 # Version
@@ -95,17 +99,34 @@ endif(EXISTS ${PROJECT_SOURCE_DIR}/.git)
 
 # Macros
 include(OpenMWMacros)
+include(WholeArchive)
 
 # doxygen main page
 
 configure_file ("${OpenMW_SOURCE_DIR}/docs/mainpage.hpp.cmake" "${OpenMW_BINARY_DIR}/docs/mainpage.hpp")
 
-option(MYGUI_STATIC "Link static build of Mygui into the binaries" FALSE)
 option(BOOST_STATIC "Link static build of Boost into the binaries" FALSE)
 option(SDL2_STATIC "Link static build of SDL into the binaries" FALSE)
-option(OSG_STATIC "Link static build of OpenSceneGraph into the binaries" FALSE)
 option(QT_STATIC "Link static build of QT into the binaries" FALSE)
 
+option(OPENMW_USE_SYSTEM_BULLET "Use system provided bullet physics library" ON)
+
+option(OPENMW_USE_SYSTEM_OSG "Use system provided OpenSceneGraph libraries" ON)
+if(OPENMW_USE_SYSTEM_OSG)
+    set(_osg_static_default OFF)
+else()
+    set(_osg_static_default ON)
+endif()
+option(OSG_STATIC "Link static build of OpenSceneGraph into the binaries" ${_osg_static_default})
+
+option(OPENMW_USE_SYSTEM_MYGUI "Use system provided mygui library" ON)
+if(OPENMW_USE_SYSTEM_MYGUI)
+    set(_mygui_static_default OFF)
+else()
+    set(_mygui_static_default ON)
+endif()
+option(MYGUI_STATIC "Link static build of Mygui into the binaries" ${_mygui_static_default})
+
 option(OPENMW_UNITY_BUILD "Use fewer compilation units to speed up compile time" FALSE)
 option(OPENMW_LTO_BUILD "Build OpenMW with Link-Time Optimization (Needs ~2GB of RAM)" OFF)
 
@@ -168,6 +189,28 @@ if (USE_QT)
     #set(CMAKE_AUTOMOC ON)
 endif()
 
+set(USED_OSG_COMPONENTS
+    osgDB
+    osgViewer
+    osgText
+    osgGA
+    osgParticle
+    osgUtil
+    osgFX
+    osgShadow
+    osgAnimation)
+set(USED_OSG_PLUGINS
+    osgdb_bmp
+    osgdb_dds
+    osgdb_freetype
+    osgdb_jpeg
+    osgdb_osg
+    osgdb_png
+    osgdb_serializers_osg
+    osgdb_tga)
+
+add_subdirectory(extern)
+
 # Sound setup
 
 # Require at least ffmpeg 3.2 for now
@@ -243,6 +286,15 @@ if (WIN32)
     add_definitions(-DNOMINMAX -DWIN32_LEAN_AND_MEAN)
 endif()
 
+if(OPENMW_USE_SYSTEM_BULLET)
+    set(REQUIRED_BULLET_VERSION 286) # Bullet 286 required due to runtime bugfixes for btCapsuleShape
+    if (DEFINED ENV{TRAVIS_BRANCH} OR DEFINED ENV{APPVEYOR})
+        set(REQUIRED_BULLET_VERSION 283) # but for build testing, 283 is fine
+    endif()
+
+    find_package(Bullet ${REQUIRED_BULLET_VERSION} REQUIRED COMPONENTS BulletCollision LinearMath)
+endif()
+
 if (NOT WIN32 AND BUILD_WIZARD) # windows users can just run the morrowind installer
     find_package(LIBUNSHIELD REQUIRED) # required only for non win32 when building openmw-wizard
     set(OPENMW_USE_UNSHIELD TRUE)
@@ -261,35 +313,25 @@ if(NOT HAVE_STDINT_H)
     message(FATAL_ERROR "stdint.h was not found" )
 endif()
 
-
+if(OPENMW_USE_SYSTEM_OSG)
-find_package(OpenSceneGraph 3.3.4 REQUIRED osgDB osgViewer osgText osgGA osgParticle osgUtil osgFX osgShadow osgAnimation)
+    find_package(OpenSceneGraph 3.3.4 REQUIRED ${USED_OSG_COMPONENTS})
-include_directories(SYSTEM ${OPENSCENEGRAPH_INCLUDE_DIRS})
+    if(OSG_STATIC)
-
+        unset(OSGPlugins_LIB_DIR)
-set(USED_OSG_PLUGINS
+        foreach(OSGDB_LIB ${OSGDB_LIBRARY})
-                    osgdb_bmp
-                    osgdb_dds
-                    osgdb_freetype
-                    osgdb_jpeg
-                    osgdb_osg
-                    osgdb_png
-                    osgdb_serializers_osg
-                    osgdb_tga
-                  )
-
-set(OSGPlugins_LIB_DIR "")
-foreach(OSGDB_LIB ${OSGDB_LIBRARY})
             # Skip library type names
             if(EXISTS ${OSGDB_LIB} AND NOT IS_DIRECTORY ${OSGDB_LIB})
                 get_filename_component(OSG_LIB_DIR ${OSGDB_LIB} DIRECTORY)
                 list(APPEND OSGPlugins_LIB_DIR "${OSG_LIB_DIR}/osgPlugins-${OPENSCENEGRAPH_VERSION}")
             endif()
-endforeach(OSGDB_LIB)
+        endforeach(OSGDB_LIB)
+        find_package(OSGPlugins REQUIRED COMPONENTS ${USED_OSG_PLUGINS})
+    endif()
+endif()
+
+include_directories(BEFORE SYSTEM ${OPENSCENEGRAPH_INCLUDE_DIRS})
 
 if(OSG_STATIC)
     add_definitions(-DOSG_LIBRARY_STATIC)
-
-    find_package(OSGPlugins REQUIRED COMPONENTS ${USED_OSG_PLUGINS})
-    list(APPEND OPENSCENEGRAPH_LIBRARIES ${OSGPlugins_LIBRARIES})
 endif()
 
 set(BOOST_COMPONENTS system filesystem program_options iostreams)
@@ -304,21 +346,18 @@ IF(BOOST_STATIC)
     set(Boost_USE_STATIC_LIBS   ON)
 endif()
 
-set(REQUIRED_BULLET_VERSION 286) # Bullet 286 required due to runtime bugfixes for btCapsuleShape
-if (DEFINED ENV{TRAVIS_BRANCH} OR DEFINED ENV{APPVEYOR})
-    set(REQUIRED_BULLET_VERSION 283) # but for build testing, 283 is fine
-endif()
-
 set(Boost_NO_BOOST_CMAKE ON)
 
 find_package(Boost 1.6.2 REQUIRED COMPONENTS ${BOOST_COMPONENTS})
-find_package(MyGUI 3.2.2 REQUIRED)
+if(OPENMW_USE_SYSTEM_MYGUI)
+    find_package(MyGUI 3.2.2 REQUIRED)
+endif()
 find_package(SDL2 2.0.9 REQUIRED)
 find_package(OpenAL REQUIRED)
-find_package(Bullet ${REQUIRED_BULLET_VERSION} REQUIRED COMPONENTS BulletCollision LinearMath)
 
-include_directories("."
+include_directories(
-    SYSTEM
+    BEFORE SYSTEM
+    "."
     ${SDL2_INCLUDE_DIR}
     ${Boost_INCLUDE_DIR}
     ${MyGUI_INCLUDE_DIRS}
@@ -846,11 +885,7 @@ elseif(NOT APPLE)
 
         # Install binaries
         IF(BUILD_OPENMW)
-            IF(ANDROID)
+            INSTALL(PROGRAMS "$<TARGET_FILE:openmw>" DESTINATION "${BINDIR}" )
-                INSTALL(PROGRAMS "${INSTALL_SOURCE}/libopenmw.so" DESTINATION "${BINDIR}" )
-            ELSE(ANDROID)
-                INSTALL(PROGRAMS "${INSTALL_SOURCE}/openmw" DESTINATION "${BINDIR}" )
-            ENDIF(ANDROID)
         ENDIF(BUILD_OPENMW)
         IF(BUILD_LAUNCHER)
             INSTALL(PROGRAMS "${INSTALL_SOURCE}/openmw-launcher" DESTINATION "${BINDIR}" )

apps/opencs/CMakeLists.txt

@@ -228,6 +228,20 @@ target_link_libraries(openmw-cs
     components
 )
 
+if(OSG_STATIC)
+    unset(_osg_plugins_static_files)
+    add_library(openmw_cs_osg_plugins INTERFACE)
+    foreach(_plugin ${USED_OSG_PLUGINS})
+        string(TOUPPER ${_plugin} _plugin_uc)
+        list(APPEND _osg_plugins_static_files $<TARGET_FILE:${${_plugin_uc}_LIBRARY}>)
+        target_link_libraries(openmw_cs_osg_plugins INTERFACE ${${_plugin_uc}_LIBRARY})
+    endforeach()
+    # We use --whole-archive because OSG plugins use registration.
+    get_whole_archive_options(_opts ${_osg_plugins_static_files})
+    target_link_options(openmw_cs_osg_plugins INTERFACE ${_opts})
+    target_link_libraries(openmw-cs openmw_cs_osg_plugins)
+endif(OSG_STATIC)
+
 target_link_libraries(openmw-cs Qt5::Widgets Qt5::Core Qt5::Network Qt5::OpenGL)
 
 if (WIN32)

apps/openmw/CMakeLists.txt

@@ -143,29 +143,22 @@ target_link_libraries(openmw
     components
 )
 
-if (ANDROID)
+if(OSG_STATIC)
-    set (OSG_PLUGINS
+    unset(_osg_plugins_static_files)
-        -Wl,--whole-archive
+    add_library(openmw_osg_plugins INTERFACE)
-    )
+    foreach(_plugin ${USED_OSG_PLUGINS})
-    foreach(PLUGIN_NAME ${USED_OSG_PLUGINS})
+        string(TOUPPER ${_plugin} _plugin_uc)
-        set(OSG_PLUGINS ${OSG_PLUGINS} ${OSG_PLUGINS_DIR}/lib${PLUGIN_NAME}.a)
+        list(APPEND _osg_plugins_static_files $<TARGET_FILE:${${_plugin_uc}_LIBRARY}>)
+        target_link_libraries(openmw_osg_plugins INTERFACE ${${_plugin_uc}_LIBRARY})
     endforeach()
+    # We use --whole-archive because OSG plugins use registration.
+    get_whole_archive_options(_opts ${_osg_plugins_static_files})
+    target_link_options(openmw_osg_plugins INTERFACE ${_opts})
+    target_link_libraries(openmw openmw_osg_plugins)
+endif(OSG_STATIC)
 
-    set (OSG_PLUGINS
+if (ANDROID)
-        ${OSG_PLUGINS} -Wl,--no-whole-archive
+    target_link_libraries(openmw EGL android log z)
-    )
-
-    target_link_libraries(openmw
-        EGL
-        android
-        log
-        dl
-        z
-        ${OPENSCENEGRAPH_LIBRARIES}
-        freetype
-        jpeg
-    	png
-    )
 endif (ANDROID)
 
 if (USE_SYSTEM_TINYXML)

cmake/WholeArchive.cmake

@@ -0,0 +1,10 @@
+function (get_whole_archive_options OUT_VAR)
+    # We use --whole-archive because OSG plugins use registration.
+    if (CMAKE_CXX_COMPILER_ID STREQUAL "Clang" OR CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
+        set(${OUT_VAR} -Wl,--whole-archive ${ARGN} -Wl,--no-whole-archive PARENT_SCOPE)
+    elseif (CMAKE_CXX_COMPILER_ID STREQUAL "AppleClang")
+        set(${OUT_VAR} -Wl,-all_load ${ARGN} -Wl,-noall_load PARENT_SCOPE)
+    else ()
+        message(FATAL_ERROR "get_whole_archive_options not implemented for CMAKE_CXX_COMPILER_ID ${CMAKE_CXX_COMPILER_ID}")
+    endif()
+endfunction ()

components/CMakeLists.txt

@@ -245,7 +245,7 @@ target_link_libraries(components
     RecastNavigation::Recast
     )
 
-if (BULLET_USE_DOUBLES AND (UBUNTU_FOUND OR DEBIAN_FOUND))
+if (BULLET_USE_DOUBLES AND (UBUNTU_FOUND OR DEBIAN_FOUND) AND OPENMW_USE_SYSTEM_BULLET)
     target_link_libraries(components BulletCollision-float64 LinearMath-float64)
 else()
     target_link_libraries(components ${BULLET_LIBRARIES})

extern/CMakeLists.txt

@@ -0,0 +1,131 @@
+# SPDX-License-Identifier: GPL-3.0-or-later
+
+# Like `FetchContent_MakeAvailable` but passes EXCLUDE_FROM_ALL to `add_subdirectory`.
+macro(FetchContent_MakeAvailableExcludeFromAll)
+    foreach(contentName IN ITEMS ${ARGV})
+        string(TOLOWER ${contentName} contentNameLower)
+        FetchContent_GetProperties(${contentName})
+        if(NOT ${contentNameLower}_POPULATED)
+            FetchContent_Populate(${contentName})
+            if(EXISTS ${${contentNameLower}_SOURCE_DIR}/CMakeLists.txt)
+                add_subdirectory(${${contentNameLower}_SOURCE_DIR}
+                    ${${contentNameLower}_BINARY_DIR} EXCLUDE_FROM_ALL)
+            endif()
+        endif()
+    endforeach()
+endmacro()
+
+if(NOT OPENMW_USE_SYSTEM_BULLET)
+    cmake_minimum_required(VERSION 3.11) # for FetchContent
+
+    set(BUILD_BULLET3 OFF CACHE BOOL "")
+    set(BUILD_EXTRAS OFF CACHE BOOL "")
+    set(BUILD_OPENGL3_DEMOS OFF CACHE BOOL "")
+    set(BUILD_UNIT_TESTS OFF CACHE BOOL "")
+    set(BUILD_BULLET2_DEMOS OFF CACHE BOOL "")
+    set(BUILD_CLSOCKET OFF CACHE BOOL "")
+    set(BUILD_ENET OFF CACHE BOOL "")
+    set(BUILD_CPU_DEMOS OFF CACHE BOOL "")
+    set(BUILD_EGL OFF CACHE BOOL "")
+
+    set(USE_DOUBLE_PRECISION ${BULLET_USE_DOUBLES} CACHE BOOL "")
+    set(BULLET2_MULTITHREADING ON CACHE BOOL "")
+
+    # Version 3.08 with the following changes:
+    # 1. Fixes the linking of Threads:
+    #    https://github.com/bulletphysics/bullet3/pull/3237
+    # 2. Removes ~300 MiB of files not used here:
+    #    rm -rf build3 data docs examples test Doxyfile
+    include(FetchContent)
+    FetchContent_Declare(bullet
+        URL https://github.com/glebm/bullet3/archive/ed5256454f4f84bd2c1728c88ddb0405d614e7d2.zip
+        URL_HASH MD5=e3c94fac35a7be885ad8843f828a0f96
+        SOURCE_DIR fetched/bullet
+    )
+    FetchContent_MakeAvailableExcludeFromAll(bullet)
+
+    set(BULLET_INCLUDE_DIRS ${bullet_SOURCE_DIR}/src PARENT_SCOPE)
+
+    # The order here is important to work around a bug in Bullet:
+    # https://github.com/bulletphysics/bullet3/issues/3233
+    set(BULLET_LIBRARIES BulletCollision LinearMath PARENT_SCOPE)
+endif()
+
+if(NOT OPENMW_USE_SYSTEM_MYGUI)
+    cmake_minimum_required(VERSION 3.11) # for FetchContent
+
+    set(MYGUI_RENDERSYSTEM 4 CACHE STRING "")
+    set(MYGUI_DISABLE_PLUGINS TRUE CACHE BOOL "")
+    set(MYGUI_BUILD_DEMOS OFF CACHE BOOL "")
+    set(MYGUI_BUILD_PLUGINS OFF CACHE BOOL "")
+    set(MYGUI_BUILD_TOOLS OFF CACHE BOOL "")
+
+    if(MYGUI_STATIC)
+        set(BUILD_SHARED_LIBS OFF)
+    else()
+        set(BUILD_SHARED_LIBS ON)
+    endif()
+
+    include(FetchContent)
+    FetchContent_Declare(mygui
+        URL https://github.com/MyGUI/mygui/archive/MyGUI3.4.0.zip
+        URL_HASH MD5=9e990a4240430cbf567bfe73488a274e
+        SOURCE_DIR fetched/mygui
+    )
+    FetchContent_MakeAvailableExcludeFromAll(mygui)
+
+    set(MyGUI_INCLUDE_DIRS ${mygui_SOURCE_DIR}/MyGUIEngine/include PARENT_SCOPE)
+    set(MyGUI_LIBRARIES MyGUIEngine PARENT_SCOPE)
+endif()
+
+if(NOT OPENMW_USE_SYSTEM_OSG)
+    cmake_minimum_required(VERSION 3.11) # for FetchContent
+
+    set(DYNAMIC_OPENTHREADS OFF CACHE BOOL "")
+    set(DYNAMIC_OPENSCENEGRAPH OFF CACHE BOOL "")
+    set(BUILD_OSG_APPLICATIONS OFF CACHE BOOL "")
+    set(BUILD_OSG_DEPRECATED_SERIALIZERS OFF CACHE BOOL "")
+    set(OSG_FIND_3RD_PARTY_DEPS OFF CACHE BOOL "")
+
+    set(BUILD_OSG_PLUGINS_BY_DEFAULT OFF CACHE BOOL "")
+    set(BUILD_OSG_PLUGIN_BMP ON CACHE BOOL "")
+    set(BUILD_OSG_PLUGIN_DDS ON CACHE BOOL "")
+    set(BUILD_OSG_PLUGIN_FREETYPE ON CACHE BOOL "")
+    set(BUILD_OSG_PLUGIN_JPEG ON CACHE BOOL "")
+    set(BUILD_OSG_PLUGIN_OSG ON CACHE BOOL "")
+    set(BUILD_OSG_PLUGIN_PNG ON CACHE BOOL "")
+    set(BUILD_OSG_PLUGIN_TGA ON CACHE BOOL "")
+    set(BUILD_OSG_PLUGIN_KTX ON CACHE BOOL "")
+
+    set(OSG_USE_FLOAT_MATRIX ON CACHE BOOL "")
+    set(OSG_USE_FLOAT_PLANE ON CACHE BOOL "")
+    set(OSG_USE_FLOAT_QUAT ON CACHE BOOL "")
+
+    set(OPENGL_PROFILE "GL2" CACHE STRING "")
+
+    if(OSG_STATIC)
+        set(BUILD_SHARED_LIBS OFF)
+    else()
+        set(BUILD_SHARED_LIBS ON)
+    endif()
+
+    # branch OpenSceneGraph-3.6 on 23 Jan 2021.
+    include(FetchContent)
+    FetchContent_Declare(osg
+        URL https://github.com/OpenMW/osg/archive/e65f47c4ab3a0b53cc19f517961671e5f840a08d.zip
+        URL_HASH MD5=0c967fe48d80744f6956f6b0b67ef7c6
+        SOURCE_DIR fetched/osg
+    )
+    FetchContent_MakeAvailableExcludeFromAll(osg)
+
+    set(OPENSCENEGRAPH_INCLUDE_DIRS ${osg_SOURCE_DIR}/include ${osg_BINARY_DIR}/include PARENT_SCOPE)
+    set(OSG_LIBRARIES OpenThreads osg PARENT_SCOPE)
+    foreach(_name ${USED_OSG_COMPONENTS})
+        string(TOUPPER ${_name} _name_uc)
+        set(${_name_uc}_LIBRARIES ${_name} PARENT_SCOPE)
+    endforeach()
+    foreach(_name ${USED_OSG_PLUGINS})
+        string(TOUPPER ${_name} _name_uc)
+        set(${_name_uc}_LIBRARY ${_name} PARENT_SCOPE)
+    endforeach()
+endif()

extern/osg-ffmpeg-videoplayer/CMakeLists.txt

@@ -13,5 +13,6 @@ set(OSG_FFMPEG_VIDEOPLAYER_SOURCE_FILES
 include_directories(${FFmpeg_INCLUDE_DIRS})
 add_library(${OSG_FFMPEG_VIDEOPLAYER_LIBRARY} STATIC ${OSG_FFMPEG_VIDEOPLAYER_SOURCE_FILES})
 target_link_libraries(${OSG_FFMPEG_VIDEOPLAYER_LIBRARY} ${FFmpeg_LIBRARIES} ${Boost_THREAD_LIBRARY})
+target_link_libraries(${OSG_FFMPEG_VIDEOPLAYER_LIBRARY} ${OSG_LIBRARIES})
 
 link_directories(${CMAKE_CURRENT_BINARY_DIR})