CI/Flatpak: Improve install behaviour

Use "standard" install path.

CMakeModules/CopyBaseTranslations.cmake

@@ -42,6 +42,8 @@ function(copy_base_translations target)
     target_sources(${target} PRIVATE ${path})
     if(APPLE)
       set_source_files_properties(${path} PROPERTIES MACOSX_PACKAGE_LOCATION Resources/translations)
+    elseif(ALLOW_INSTALL)
+      install(FILES "${path}" DESTINATION "${CMAKE_INSTALL_BINDIR}/translations")
     else()
       add_custom_command(TARGET ${target} POST_BUILD
         COMMAND "${CMAKE_COMMAND}" -E copy_if_different "${path}" "$<TARGET_FILE_DIR:${target}>/translations")

CMakeModules/DuckStationBuildOptions.cmake

@@ -10,6 +10,7 @@ if(LINUX OR BSD)
   option(ENABLE_X11 "Support X11 window system" ON)
   option(ENABLE_WAYLAND "Support Wayland window system" ON)
   option(ALLOW_INSTALL "Allow installation to CMAKE_INSTALL_PREFIX" OFF)
+  option(INSTALL_SELF_CONTAINED "Make self-contained install, i.e. everything in one directory" ON)
 endif()
 if(APPLE)
   option(SKIP_POSTPROCESS_BUNDLE "Disable bundle post-processing, including Qt additions" OFF)

CMakeModules/DuckStationBuildSummary.cmake

@@ -28,6 +28,13 @@ if(ALLOW_INSTALL)
   message(WARNING "Install target is enabled. This will install all DuckStation files into:
   ${CMAKE_INSTALL_PREFIX}
 It does **not** use the LSB subdirectories of bin, share, etc, so you should disable this option if it is set to /usr or /usr/local.")
+
+  if(INSTALL_SELF_CONTAINED)
+    message(STATUS "Creating self-contained install at ${CMAKE_INSTALL_PREFIX}")
+  else()
+    message(STATUS "Creating relative install at ${CMAKE_INSTALL_PREFIX}")
+    message(STATUS "  CMAKE_INSTALL_BINDIR: ${CMAKE_INSTALL_BINDIR}")
+  endif()
 endif()
 
 if(NOT IS_SUPPORTED_COMPILER)

CMakeModules/DuckStationUtils.cmake

@@ -225,5 +225,5 @@ endfunction()
 function(install_imported_dep_library name)
   get_target_property(SONAME "${name}" IMPORTED_SONAME_RELEASE)
   get_target_property(LOCATION "${name}" IMPORTED_LOCATION_RELEASE)
-  install(FILES "${LOCATION}" RENAME "${SONAME}" DESTINATION "${CMAKE_INSTALL_PREFIX}")
+  install(FILES "${LOCATION}" RENAME "${SONAME}" DESTINATION "${CMAKE_INSTALL_LIBDIR}")
 endfunction()

CMakeModules/FindLibbacktrace.cmake

@@ -6,14 +6,14 @@
 
 FIND_PATH(
     LIBBACKTRACE_INCLUDE_DIR backtrace.h
-    HINTS /usr/include /usr/local/include
+    HINTS "${CMAKE_PREFIX_PATH}/include" /usr/include /usr/local/include
     ${LIBBACKTRACE_PATH_INCLUDES}
 )
 
 FIND_LIBRARY(
     LIBBACKTRACE_LIBRARY
     NAMES backtrace
-    PATHS ${ADDITIONAL_LIBRARY_PATHS} ${LIBBACKTRACE_PATH_LIB}
+    PATHS "${CMAKE_PREFIX_PATH}/lib" "${CMAKE_PREFIX_PATH}/lib64" ${ADDITIONAL_LIBRARY_PATHS} ${LIBBACKTRACE_PATH_LIB}
 )
 
 include(FindPackageHandleStandardArgs)