video/out/vo_gpu_next: don't make sdr-adjust-gamma=auto behave like "no" on macOS

On macOS, global color management is always enabled, so there's no need to
make "auto" behave like "no".

Signed-off-by: Shengyu Qu <[email protected]>

Author: Headcrabed

DOCS/man/options.rst

@@ -7377,7 +7377,8 @@ them.
     ``yes``, it will be converted based on the available metadata.
 
     ``auto`` (default) behaves like ``no``, except when ``--target-trc`` is
-    explicitly set, in which case it behaves like ``yes``.
+    explicitly set, in which case it behaves like ``yes``. On macOS it
+    should always behave like ``yes``.
 
     Generally it's recommended to enable this option, if you can ensure that
     both source and target metadata is correct. Besides, on color managed

video/out/vo_gpu_next.c

@@ -1272,6 +1272,10 @@ static bool draw_frame(struct vo *vo, struct vo_frame *frame)
         case PL_COLOR_TRC_BT_1886:
         case PL_COLOR_TRC_GAMMA22:
         case PL_COLOR_TRC_SRGB:
+#ifdef __APPLE__
+            if (opts->sdr_adjust_gamma == 0)
+                break;
+#endif
             target.color.transfer = frame->current->params.color.transfer;
         }
     }