options: implement --pphelp differently

Make it work via --vf=pp:help instead.

DOCS/man/en/changes.rst

@@ -177,6 +177,7 @@ Command Line Switches
     ``-zoom``                   Inverse available as ``--video-unscaled``
     ``-panscanrange``           ``--video-zoom``, ``--video-pan-x/y``
     ``-pp``                     ``-vf=pp``
+    ``-pphelp``                 ``--vf=pp:help``
     =========================== ========================================
 
 .. note::

DOCS/man/en/options.rst

@@ -1620,9 +1620,6 @@ OPTIONS
 
         FIXME: This needs to be clarified and documented thoroughly.
 
-``--pphelp``
-    See also ``--vf=pp``.
-
 ``--priority=<prio>``
     (Windows only.)
     Set process priority for mpv according to the predefined priorities

DOCS/man/en/vf.rst

@@ -250,7 +250,7 @@ Available filters are:
 
     .. note::
 
-        ``--pphelp`` shows a list of available subfilters.
+        ``--vf=pp:help`` shows a list of available subfilters.
 
     Available subfilters are:
 

mpvcore/options.c

@@ -61,7 +61,6 @@ extern const m_option_t demux_rawvideo_opts[];
 extern const m_option_t cdda_opts[];
 
 extern int sws_flags;
-extern const char pp_help[];
 
 extern const char mp_help_text[];
 
@@ -491,10 +490,6 @@ const m_option_t mp_opts[] = {
                 {"vaapi-copy", 5})),
     OPT_STRING("hwdec-codecs", hwdec_codecs, 0),
 
-#if HAVE_LIBPOSTPROC
-    {"pphelp", (void *) &pp_help, CONF_TYPE_PRINT, CONF_GLOBAL | CONF_NOCFG, 0, 0, NULL},
-#endif
-
     // scaling:
     {"sws", &sws_flags, CONF_TYPE_INT, 0, 0, 2, NULL},
     {"ssf", (void *) scaler_filter_conf, CONF_TYPE_SUBCONFIG, 0, 0, 0, NULL},

video/filter/vf.c

@@ -131,6 +131,7 @@ static bool get_desc(struct m_obj_desc *dst, int index)
         .priv_defaults = vf->priv_defaults,
         .options = vf->options,
         .p = vf,
+        .print_help = vf->print_help,
     };
     return true;
 }

video/filter/vf.h

@@ -38,6 +38,7 @@ typedef struct vf_info {
     int priv_size;
     const void *priv_defaults;
     const struct m_option *options;
+    void (*print_help)(void);
 } vf_info_t;
 
 struct vf_format {

video/filter/vf_pp.c

@@ -153,10 +153,16 @@ static int vf_open(vf_instance_t *vf, char *args){
     return 1;
 }
 
+static void print_help(void)
+{
+    mp_msg(MSGT_CFGPARSER, MSGL_INFO, "%s", pp_help);
+}
+
 const vf_info_t vf_info_pp = {
     .description = "postprocessing",
     .name = "pp",
     .open = vf_open,
+    .print_help = print_help,
 };
 
 //===========================================================================//