Initial commit

added libraries:
opus
flac
libsndfile

updated:
libvorbis
libogg
openal

- Everything works as expected for now. Bare in mind libsndfile needed the check for whether or not it could find the xiph libraries removed in order for this to work.

Engine/lib/libvorbis/cmake/FindOgg.cmake

@@ -0,0 +1,94 @@
+#[=======================================================================[.rst:
+
+FindOgg
+--------
+
+Find the native Ogg includes and library.
+
+IMPORTED Targets
+^^^^^^^^^^^^^^^^
+
+This module defines :prop_tgt:`IMPORTED` target ``Ogg::ogg``, if
+Ogg has been found.
+
+Result Variables
+^^^^^^^^^^^^^^^^
+
+This module defines the following variables:
+
+::
+
+  OGG_INCLUDE_DIRS    - where to find ogg.h, etc.
+  OGG_LIBRARIES       - List of libraries when using ogg.
+  OGG_FOUND           - True if ogg found.
+
+::
+
+  OGG_VERSION_STRING  - The version of ogg found (x.y.z)
+
+Hints
+^^^^^
+
+A user may set ``OGG_ROOT`` to a ogg installation root to tell this
+module where to look.
+#]=======================================================================]
+
+if(OGG_INCLUDE_DIR)
+  # Already in cache, be silent
+  set(OGG_FIND_QUIETLY TRUE)
+endif()
+
+find_package(PkgConfig QUIET)
+pkg_check_modules(PC_OGG QUIET ogg)
+
+set(OGG_VERSION_STRING ${PC_OGG_VERSION})
+
+find_path(OGG_INCLUDE_DIR ogg/ogg.h
+    HINTS
+        ${PC_OGG_INCLUDEDIR}
+        ${PC_OGG_INCLUDE_DIRS}
+        ${OGG_ROOT}
+    PATH_SUFFIXES
+        include
+)
+# MSVC built ogg may be named ogg_static.
+# The provided project files name the library with the lib prefix.
+find_library(OGG_LIBRARY
+    NAMES
+        ogg
+        ogg_static
+        libogg
+        libogg_static
+    HINTS
+        ${PC_OGG_LIBDIR}
+        ${PC_OGG_LIBRARY_DIRS}
+        ${OGG_ROOT}
+    PATH_SUFFIXES
+        lib
+)
+
+# Handle the QUIETLY and REQUIRED arguments and set OGG_FOUND
+# to TRUE if all listed variables are TRUE.
+include(FindPackageHandleStandardArgs)
+find_package_handle_standard_args(Ogg
+    REQUIRED_VARS
+        OGG_LIBRARY
+        OGG_INCLUDE_DIR
+    VERSION_VAR
+        OGG_VERSION_STRING
+)
+
+if(OGG_FOUND)
+    set(OGG_LIBRARIES ${OGG_LIBRARY})
+    set(OGG_INCLUDE_DIRS ${OGG_INCLUDE_DIR})
+
+    if(NOT TARGET Ogg::ogg)
+    add_library(Ogg::ogg UNKNOWN IMPORTED)
+        set_target_properties(Ogg::ogg PROPERTIES
+            INTERFACE_INCLUDE_DIRECTORIES "${OGG_INCLUDE_DIRS}"
+            IMPORTED_LOCATION "${OGG_LIBRARIES}"
+        )
+  endif()
+endif()
+
+mark_as_advanced(OGG_INCLUDE_DIR OGG_LIBRARY)

Engine/lib/libvorbis/cmake/VorbisConfig.cmake.in

@@ -0,0 +1,19 @@
+@PACKAGE_INIT@
+
+include(CMakeFindDependencyMacro)
+find_dependency(Ogg REQUIRED)
+
+include(${CMAKE_CURRENT_LIST_DIR}/VorbisTargets.cmake)
+
+set(Vorbis_Vorbis_FOUND 1)
+set(Vorbis_Enc_FOUND 0)
+set(Vorbis_File_FOUND 0)
+
+if(TARGET Vorbis::vorbisenc)
+    set(Vorbis_Enc_FOUND TRUE)
+endif()
+if(TARGET Vorbis::vorbisfile)
+    set(Vorbis_File_FOUND TRUE)
+endif()
+
+check_required_components(Vorbis Enc File)