vo_gpu_next: add missing --gamut-mapping-mode options

Adds the missing upstream values that were exposed by the new gamut
mapping API.

DOCS/interface-changes.rst

@@ -76,6 +76,7 @@ Interface changes
       save cache files for these features; explictly setting `--icc-cache-dir` and
       `--gpu-shader-cache` is no longer required
     - remove the `--tone-mapping-crosstalk` option
+    - add `--gamut-mapping-mode=perceptual|relative|saturation|absolute|linear`
  --- mpv 0.35.0 ---
     - add the `--vo=gpu-next` video output driver, as well as the options
       `--allow-delayed-peak-detect`, `--builtin-scalers`,

DOCS/man/options.rst

@@ -6565,16 +6565,36 @@ them.
     auto
         Choose the best mode automatically. (Default)
     clip
-        Hard-clip to the gamut (per-channel).
-    warn
-        Simply highlight out-of-gamut pixels.
-    desaturate
-        Chromatically desaturate out-of-gamut colors towards white.
-    darken
-        Linearly darken the entire image, then clip to the color volume. Unlike
-        ``clip``, this does not destroy detail in saturated regions, but comes
-        at the cost of sometimes significantly lowering output brightness.
+        Hard-clip to the gamut (per-channel). Very low quality, but free.
+    perceptual
+        Performs a perceptually balanced gamut mapping using a soft knee
+        function to roll-off clipped regions, and a hue shifting function to
+        preserve saturation. (``--vo=gpu-next`` only)
+    relative
+        Performs relative colorimetric clipping, while maintaining an
+        exponential relationship between brightness and chromaticity.
         (``--vo=gpu-next`` only)
+    saturation
+        Performs simple RGB->RGB saturation mapping. The input R/G/B channels
+        are mapped directly onto the output R/G/B channels. Will never clip,
+        but will distort all hues and/or result in a faded look.
+        (``--vo=gpu-next`` only)
+    absolute
+        Performs absolute colorimetric clipping. Like ``relative``, but does
+        not adapt the white point. (``--vo=gpu-next`` only)
+    desaturate
+        Performs constant-luminance colorimetric clipping, desaturing colors
+        towards white until they're in-range.
+    darken
+        Uniformly darkens the input slightly to prevent clipping on blown-out
+        highlights, then clamps colorimetrically to the input gamut boundary,
+        biased slightly to preserve chromaticity over luminance.
+        (``--vo=gpu-next`` only)
+    warn
+        Performs no gamut mapping, but simply highlights out-of-gamut pixels.
+    linear
+        Linearly/uniformly desaturates the image in order to bring the entire
+        image into the target gamut. (``--vo=gpu-next`` only)
 
 ``--hdr-compute-peak=<auto|yes|no>``
     Compute the HDR peak and frame average brightness per-frame instead of

video/out/gpu/video.c

@@ -400,9 +400,14 @@ const struct m_sub_options gl_video_conf = {
         {"gamut-mapping-mode", OPT_CHOICE(tone_map.gamut_mode,
             {"auto",        GAMUT_AUTO},
             {"clip",        GAMUT_CLIP},
-            {"warn",        GAMUT_WARN},
+            {"perceptual",  GAMUT_PERCEPTUAL},
+            {"relative",    GAMUT_RELATIVE},
+            {"saturation",  GAMUT_SATURATION},
+            {"absolute",    GAMUT_ABSOLUTE},
             {"desaturate",  GAMUT_DESATURATE},
-            {"darken",      GAMUT_DARKEN})},
+            {"darken",      GAMUT_DARKEN},
+            {"warn",        GAMUT_WARN},
+            {"linear",      GAMUT_LINEAR})},
         {"hdr-compute-peak", OPT_CHOICE(tone_map.compute_peak,
             {"auto", 0},
             {"yes", 1},

video/out/gpu/video.h

@@ -113,9 +113,14 @@ enum tone_mapping_mode {
 enum gamut_mode {
     GAMUT_AUTO,
     GAMUT_CLIP,
-    GAMUT_WARN,
+    GAMUT_PERCEPTUAL,
+    GAMUT_RELATIVE,
+    GAMUT_SATURATION,
+    GAMUT_ABSOLUTE,
     GAMUT_DESATURATE,
     GAMUT_DARKEN,
+    GAMUT_WARN,
+    GAMUT_LINEAR,
 };
 
 struct gl_tone_map_opts {

video/out/vo_gpu_next.c

@@ -1862,9 +1862,14 @@ static void update_render_options(struct vo *vo)
 #if PL_API_VER >= 269
     const struct pl_gamut_map_function *gamut_modes[] = {
         [GAMUT_CLIP]            = &pl_gamut_map_clip,
-        [GAMUT_WARN]            = &pl_gamut_map_highlight,
+        [GAMUT_PERCEPTUAL]      = &pl_gamut_map_perceptual,
+        [GAMUT_RELATIVE]        = &pl_gamut_map_relative,
+        [GAMUT_SATURATION]      = &pl_gamut_map_saturation,
+        [GAMUT_ABSOLUTE]        = &pl_gamut_map_absolute,
         [GAMUT_DESATURATE]      = &pl_gamut_map_desaturate,
         [GAMUT_DARKEN]          = &pl_gamut_map_darken,
+        [GAMUT_WARN]            = &pl_gamut_map_highlight,
+        [GAMUT_LINEAR]          = &pl_gamut_map_linear,
     };
 
     // Back-compat approximation, taken from libplacebo source code
@@ -1880,6 +1885,12 @@ static void update_render_options(struct vo *vo)
         [GAMUT_WARN]            = PL_GAMUT_WARN,
         [GAMUT_DESATURATE]      = PL_GAMUT_DESATURATE,
         [GAMUT_DARKEN]          = PL_GAMUT_DARKEN,
+        // Unsupported
+        [GAMUT_PERCEPTUAL]      = PL_GAMUT_CLIP,
+        [GAMUT_RELATIVE]        = PL_GAMUT_CLIP,
+        [GAMUT_SATURATION]      = PL_GAMUT_CLIP,
+        [GAMUT_ABSOLUTE]        = PL_GAMUT_CLIP,
+        [GAMUT_LINEAR]          = PL_GAMUT_CLIP,
     };
 
     static const enum pl_tone_map_mode tone_map_modes[] = {