Update docs and tag info

README.md

@@ -46,25 +46,26 @@ or in a system directory, or any other directory in the PATH variable.
 ```
 Usage: test.exe [-o outfile.wav] [options] infile
 Options:
-    -o outfile.wav: name of output .wav file, default is infile.wav
+    -o outfile.wav: name of output .wav file, default infile.wav
     -l loop count: loop count, default 2.0
-    -f fade time: fade time (seconds), default 10.0
-    -d fade delay: fade delay (seconds, default 0.0
+    -f fade time: fade time in seconds after N loops, default 10.0
+    -d fade delay: fade delay in seconds, default 0.0
+    -F: don't fade after N loops and play the rest of the stream
     -i: ignore looping information and play the whole stream once
+    -e: force end-to-end looping
+    -E: force end-to-end looping even if file has real loop points
+    -s N: select subsong N, if the format supports multiple subsongs
+    -m: print metadata only, don't decode
+    -L: append a smpl chunk and create a looping wav
+    -2 N: only output the Nth (first is 0) set of stereo channels
     -p: output to stdout (for piping into another program)
     -P: output to stdout even if stdout is a terminal
-    -c: loop forever (continuously)
-    -m: print metadata only, don't decode
+    -c: loop forever (continuously) to stdout
     -x: decode and print adxencd command line to encode as ADX
     -g: decode and print oggenc command line to encode as OGG
     -b: decode and print batch variable commands
-    -L: append a smpl chunk and create a looping wav
-    -e: force end-to-end looping
-    -E: force end-to-end looping even if file has real loop points
-    -r outfile2.wav: output a second time after resetting
-    -2 N: only output the Nth (first is 0) set of stereo channels
-    -F: don't fade after N loops and play the rest of the stream
-    -s N: select subsong N, if the format supports multiple subsongs
+    -r: output a second file after resetting (for testing)
+    -t file: print if tags are found in file
 ```
 Typical usage would be: ```test -o happy.wav happy.adx``` to decode ```happy.adx``` to ```happy.wav```.
 
@@ -232,6 +233,32 @@ Creation of those files is meant for advanced users, docs can be found in
 vgmstream source.
 
 
+## Tagging
+Some of vgmstream's plugins support simple read-only tagging via external files.
+
+Tags are loaded from a text/M3U-like file named _!tags.m3u_ in the song folder.
+You don't have to load your songs with that M3U though (but you can, for pre-made
+ordering), the file itself just 'looks' like an M3U.
+
+Format is:
+```
+# ignored comment
+# @GLOBAL_TAG value (applies all following tracks)
+
+# %LOCAL_TAG value (applies to next track only)
+filename1
+# %LOCAL_TAG value (applies to next track only)
+filename2
+```
+Accepted tags depend on the player (foobar: any; winamp: see ATF config),
+typically ALBUM/ARTIST/TITLE/DISC/TRACK/COMPOSER/etc, lower or uppercase,
+separated by one or multiple spaces. Repeated tags overwrite previous
+(ex.- may define @COMPOSER for multiple tracks). It only reads up to current
+_filename_ though, so any @TAG below would be ignored.
+
+Playlist formatting should follow player's config. ASCII or UTF-8 tags work.
+
+
 ## Supported codec types
 Quick list of codecs vgmstream supports, including many obscure ones that 
 are used in few games.

doc/TXTP.md

@@ -102,7 +102,7 @@ file2.ext#m2-3,4-5,4-6  # ogg "FL CN FR BL BR SB" to wav "FL FR CN SB BL BR"
 Those setting should override player's defaults if set (except "loop forever"). They are equivalent to some test.exe options.
 
 - __God Hand (PS2)__: _boss2_3ningumi_ver6.txtp_ (each line is a separate TXTP)
-<EFBFBD><EFBFBD><EFBFBD>
+```
 # set number of loops
 boss2_3ningumi_ver6.adx#l3
 
@@ -128,7 +128,7 @@ boss2_3ningumi_ver6.adx#l2#F  # 2 loops + ending
 boss2_3ningumi_ver6.adx#l1.5#d1#f5
 
 # boss2_3ningumi_ver6.adx#l1.0#F  # this is equivalent to #i
-<EFBFBD><EFBFBD><EFBFBD><EFBFBD>
+```
 
 For segments and layers the first file defines looping options.