CMake: use FFmpeg find module on Linux

And change install_deps.sh to build shared (instead of static) FFMPEG
libraries, for consistency with other library dependencies and to simplify
the logic. This may require users of install_deps.sh to rebuild FFMPEG.

This is the last step that lets us get rid of LIBPATH variables and
link_directories() entirely, as recommended by the CMake docs.

Some fixes were needed in the find FFMPEG module to make it actually work,
this code was unused up to now.

Followup to D8855.

Differential Revision: https://developer.blender.org/D9177

build_files/build_environment/install_deps.sh

@@ -3620,8 +3620,8 @@ compile_FFmpeg() {
     fi
 
     ./configure --cc="gcc -Wl,--as-needed" \
-        --extra-ldflags="-pthread -static-libgcc" \
-        --prefix=$_inst --enable-static \
+        --extra-ldflags="-pthread" \
+        --prefix=$_inst --enable-shared \
         --disable-ffplay --disable-doc \
         --enable-gray \
         --enable-avfilter --disable-vdpau \
@@ -5721,76 +5721,6 @@ install_OTHER() {
 # ----------------------------------------------------------------------------
 # Printing User Info
 
-print_info_ffmpeglink_DEB() {
-  dpkg -L $_packages | grep -e ".*\/lib[^\/]\+\.so" | gawk '{ printf(nlines ? "'"$_ffmpeg_list_sep"'%s" : "%s", gensub(/.*lib([^\/]+)\.so/, "\\1", "g", $0)); nlines++ }'
-}
-
-print_info_ffmpeglink_RPM() {
-  rpm -ql $_packages | grep -e ".*\/lib[^\/]\+\.so" | gawk '{ printf(nlines ? "'"$_ffmpeg_list_sep"'%s" : "%s", gensub(/.*lib([^\/]+)\.so/, "\\1", "g", $0)); nlines++ }'
-}
-
-print_info_ffmpeglink_ARCH() {
-  pacman -Ql $_packages | grep -e ".*\/lib[^\/]\+\.so$" | gawk '{ printf(nlines ? "'"$_ffmpeg_list_sep"'%s" : "%s", gensub(/.*lib([^\/]+)\.so/, "\\1", "g", $0)); nlines++ }'
-}
-
-print_info_ffmpeglink() {
-  # This func must only print a ';'-separated list of libs...
-  if [ -z "$DISTRO" ]; then
-    ERROR "Failed to detect distribution type"
-    exit 1
-  fi
-
-  # Create list of packages from which to get libs names...
-  _packages=""
-
-  if [ "$THEORA_USE" = true ]; then
-    _packages="$_packages $THEORA_DEV"
-  fi
-
-  if [ "$VORBIS_USE" = true ]; then
-    _packages="$_packages $VORBIS_DEV"
-  fi
-
-  if [ "$OGG_USE" = true ]; then
-    _packages="$_packages $OGG_DEV"
-  fi
-
-  if [ "$XVID_USE" = true ]; then
-    _packages="$_packages $XVID_DEV"
-  fi
-
-  if [ "$VPX_USE" = true ]; then
-    _packages="$_packages $VPX_DEV"
-  fi
-
-  if [ "$OPUS_USE" = true ]; then
-    _packages="$_packages $OPUS_DEV"
-  fi
-
-  if [ "$MP3LAME_USE" = true ]; then
-    _packages="$_packages $MP3LAME_DEV"
-  fi
-
-  if [ "$X264_USE" = true ]; then
-    _packages="$_packages $X264_DEV"
-  fi
-
-  if [ "$OPENJPEG_USE" = true ]; then
-    _packages="$_packages $OPENJPEG_DEV"
-  fi
-
-  if [ "$DISTRO" = "DEB" ]; then
-    print_info_ffmpeglink_DEB
-  elif [ "$DISTRO" = "RPM" ]; then
-    print_info_ffmpeglink_RPM
-  elif [ "$DISTRO" = "ARCH" ]; then
-    print_info_ffmpeglink_ARCH
-  # XXX TODO!
-  else
-    PRINT "<Could not determine additional link libraries needed for ffmpeg, replace this by valid list of libs...>"
-  fi
-}
-
 print_info() {
   PRINT ""
   PRINT ""
@@ -6002,12 +5932,10 @@ print_info() {
 
   if [ "$FFMPEG_SKIP" = false ]; then
     _1="-D WITH_CODEC_FFMPEG=ON"
-    _2="-D FFMPEG_LIBRARIES='avformat;avcodec;avutil;avdevice;swscale;swresample;lzma;rt;`print_info_ffmpeglink`'"
     PRINT "  $_1"
-    PRINT "  $_2"
-    _buildargs="$_buildargs $_1 $_2"
+    _buildargs="$_buildargs $_1"
     if [ -d $INST/ffmpeg ]; then
-      _1="-D FFMPEG=$INST/ffmpeg"
+      _1="-D FFMPEG_ROOT_DIR=$INST/ffmpeg"
       PRINT "  $_1"
       _buildargs="$_buildargs $_1"
     fi

build_files/cmake/Modules/FindFFmpeg.cmake

@@ -33,6 +33,8 @@ if(NOT FFMPEG_FIND_COMPONENTS)
     avfilter
     avformat
     avutil
+    swscale
+    swresample
   )
 endif()
 
@@ -50,9 +52,9 @@ foreach(_component ${FFMPEG_FIND_COMPONENTS})
   string(TOUPPER ${_component} _upper_COMPONENT)
   find_library(FFMPEG_${_upper_COMPONENT}_LIBRARY
     NAMES
-      ${_upper_COMPONENT}
+      ${_component}
     HINTS
-      ${LIBDIR}/ffmpeg
+      ${_ffmpeg_SEARCH_DIRS}
     PATH_SUFFIXES
       lib64 lib
   )

build_files/cmake/platform/platform_apple.cmake

@@ -173,6 +173,7 @@ if(WITH_IMAGE_OPENEXR)
 endif()
 
 if(WITH_CODEC_FFMPEG)
+  set(FFMPEG_ROOT_DIR ${LIBDIR}/ffmpeg)
   set(FFMPEG_FIND_COMPONENTS
     avcodec avdevice avformat avutil
     mp3lame ogg opus swresample swscale

build_files/cmake/platform/platform_unix.cmake

@@ -178,26 +178,24 @@ endif()
 
 if(WITH_CODEC_FFMPEG)
   if(EXISTS ${LIBDIR})
-    # For precompiled lib directory, all ffmpeg dependencies are in the same folder
-    file(GLOB ffmpeg_libs ${LIBDIR}/ffmpeg/lib/*.a ${LIBDIR}/sndfile/lib/*.a)
-    set(FFMPEG ${LIBDIR}/ffmpeg CACHE PATH "FFMPEG Directory")
-    set(FFMPEG_LIBRARIES ${ffmpeg_libs} ${ffmpeg_libs} CACHE STRING "FFMPEG Libraries")
-  else()
-    set(FFMPEG /usr CACHE PATH "FFMPEG Directory")
-    set(FFMPEG_LIBRARIES avformat avcodec avutil avdevice swscale CACHE STRING "FFMPEG Libraries")
+    set(FFMPEG_ROOT_DIR ${LIBDIR}/ffmpeg)
+    # Override FFMPEG components to also include static library dependencies.
+    # included with precompiled libraries.
+    set(FFMPEG_FIND_COMPONENTS
+      avcodec avdevice avformat avutil
+      mp3lame ogg opus swresample swscale
+      theora theoradec theoraenc vorbis vorbisenc
+      vorbisfile vpx x264 xvidcore)
+  elseif(FFMPEG)
+    # Old cache variable used for root dir, convert to new standard.
+    set(FFMPEG_ROOT_DIR ${FFMPEG})
   endif()
+  find_package(FFmpeg)
 
-  mark_as_advanced(FFMPEG)
-
-  # lame, but until we have proper find module for ffmpeg
-  set(FFMPEG_INCLUDE_DIRS ${FFMPEG}/include)
-  if(EXISTS "${FFMPEG}/include/ffmpeg/")
-    list(APPEND FFMPEG_INCLUDE_DIRS "${FFMPEG}/include/ffmpeg")
+  if(NOT FFMPEG_FOUND)
+    set(WITH_CODEC_FFMPEG OFF)
+    message(STATUS "FFmpeg not found, disabling it")
   endif()
-  # end lameness
-
-  mark_as_advanced(FFMPEG_LIBRARIES)
-  set(FFMPEG_LIBPATH ${FFMPEG}/lib)
 endif()
 
 if(WITH_FFTW3)