Replace non-leading tabs with spaces, using:

find -type f |  # list all regular files
  grep -E '\.(h|cpp|mm)$' |  # filter for source files
  grep -v '/mt_' |  # filter out generated files
  grep -v '/vendor/' | # and vendored GL
  xargs -n 1 -P $(nproc) ./replace_non_leading_tabs.lua  # reformat everything

source/Irrlicht/CImageWriterJPG.cpp

@@ -27,7 +27,7 @@ typedef struct
 {
 	struct jpeg_destination_mgr pub; /* public fields */
 
-	io::IWriteFile *file;			/* target file */
+	io::IWriteFile *file;           /* target file */
 	JOCTET buffer[OUTPUT_BUF_SIZE]; /* image buffer */
 } mem_destination_mgr;