Disable FFMpeg GPU video acceleration on Linux

CMake/SetupFfmpeg.cmake

@@ -1,15 +1,7 @@
 set(SM_FFMPEG_VERSION "3.3.3")
-set(SM_FFMPEG_SRC_LIST "${SM_EXTERN_DIR}" "/ffmpeg-linux-" "${SM_FFMPEG_VERSION}")
+set(SM_FFMPEG_SRC_LIST "${SM_EXTERN_DIR}/ffmpeg-linux-${SM_FFMPEG_VERSION}")
 sm_join("${SM_FFMPEG_SRC_LIST}" "" SM_FFMPEG_SRC_DIR)
 set(SM_FFMPEG_CONFIGURE_EXE "${SM_FFMPEG_SRC_DIR}/configure")
-if (MINGW)
-  # Borrow from http://stackoverflow.com/q/11845823
-  # string(SUBSTRING ${SM_FFMPEG_CONFIGURE_EXE} 0 1 FIRST_LETTER)
-  # string(TOLOWER ${FIRST_LETTER} FIRST_LETTER_LOW)
-  # string(REPLACE "${FIRST_LETTER}:" "/${FIRST_LETTER_LOW}" # SM_FFMPEG_CONFIGURE_EXE ${SM_FFMPEG_CONFIGURE_EXE})
-  # string(REGEX REPLACE "\\\\" "/" SM_FFMPEG_CONFIGURE_EXE "${SM_FFMPEG_CONFIGURE_EXE}")
-  set(SM_FFMPEG_CONFIGURE_EXE "extern/ffmpeg-linux-${SM_FFMPEG_VERSION}/configure")
-endif()
 list(APPEND FFMPEG_CONFIGURE
   "${SM_FFMPEG_CONFIGURE_EXE}"
   "--disable-muxers"
@@ -25,6 +17,12 @@ if(CMAKE_POSITION_INDEPENDENT_CODE)
     list(APPEND FFMPEG_CONFIGURE "--enable-pic")
 endif()
 
+if (LINUX)
+  # TODO: Figure out how to build with hardware video acceleration.
+  # These options cause link issues when not disabled.
+  list(APPEND FFMPEG_CONFIGURE "--disable-vaapi" "--disable-vdpau")
+endif()
+
 if(MACOSX)
   # TODO: Remove these two items when Mac OS X StepMania builds in 64-bit.
   list(APPEND FFMPEG_CONFIGURE
@@ -38,14 +36,10 @@ if (WITH_CRYSTALHD_DISABLED)
 endif()
 
 if (NOT WITH_EXTERNAL_WARNINGS)
-  list(APPEND FFMPEG_CONFIGURE
-    "--extra-cflags=-w"
-  )
+  list(APPEND FFMPEG_CONFIGURE "--extra-cflags=-w")
 endif()
 
-list(APPEND SM_FFMPEG_MAKE
-  $(MAKE)
-)
+list(APPEND SM_FFMPEG_MAKE $(MAKE))
 if (WITH_FFMPEG_JOBS GREATER 0)
   list(APPEND SM_FFMPEG_MAKE "-j${WITH_FFMPEG_JOBS}")
 endif()
@@ -60,7 +54,6 @@ if (IS_DIRECTORY "${SM_FFMPEG_SRC_DIR}")
     TEST_COMMAND ""
   )
 else()
-  # --shlibdir=$our_installdir/stepmania-$VERSION
   externalproject_add("ffmpeg"
     DOWNLOAD_COMMAND git clone "--depth" "1" "git://github.com/etternagame/FFmpeg.git" "${SM_FFMPEG_SRC_DIR}"
     CONFIGURE_COMMAND "${FFMPEG_CONFIGURE}"
@@ -73,4 +66,3 @@ endif()
 
 externalproject_get_property("ffmpeg" BINARY_DIR)
 set(SM_FFMPEG_ROOT ${BINARY_DIR})
-