Add support for manually setting subpixel hinting on outputs.

Many laptop screens report unknown subpixel order. Allow users to manually set subpixel hinting to work around this.

Addresses https://github.com/swaywm/sway/issues/3163

1 files changed, 19 insertions, 4 deletions

diff --git a/sway/config/output.c b/sway/config/output.c
index 44aae03a..d06051b3 100644
--- a/sway/config/output.c
+++ b/sway/config/output.c
@@ -8,10 +8,11 @@
 #include <unistd.h>
 #include <wlr/types/wlr_output_layout.h>
 #include <wlr/types/wlr_output.h>
-#include "log.h"
 #include "sway/config.h"
 #include "sway/output.h"
 #include "sway/tree/root.h"
+#include "log.h"
+#include "util.h"
 
 int output_name_cmp(const void *item, const void *data) {
         const struct output_config *output = item;
@@ -43,6 +44,7 @@ struct output_config *new_output_config(const char *name) {
         oc->x = oc->y = -1;
         oc->scale = -1;
         oc->transform = -1;
+        oc->subpixel = WL_OUTPUT_SUBPIXEL_UNKNOWN;
         return oc;
 }
 
@@ -65,6 +67,9 @@ void merge_output_config(struct output_config *dst, struct output_config *src) {
         if (src->scale != -1) {
                 dst->scale = src->scale;
         }
+        if (src->subpixel != WL_OUTPUT_SUBPIXEL_UNKNOWN) {
+                dst->subpixel = src->subpixel;
+        }
         if (src->refresh_rate != -1) {
                 dst->refresh_rate = src->refresh_rate;
         }
@@ -187,10 +192,10 @@ struct output_config *store_output_config(struct output_config *oc) {
         }
 
         sway_log(SWAY_DEBUG, "Config stored for output %s (enabled: %d) (%dx%d@%fHz "
-                "position %d,%d scale %f transform %d) (bg %s %s) (dpms %d)",
+                "position %d,%d scale %f subpixel %s transform %d) (bg %s %s) (dpms %d)",
                 oc->name, oc->enabled, oc->width, oc->height, oc->refresh_rate,
-                oc->x, oc->y, oc->scale, oc->transform, oc->background,
-                oc->background_option, oc->dpms_state);
+                oc->x, oc->y, oc->scale, sway_wl_output_subpixel_to_string(oc->subpixel),
+                oc->transform, oc->background, oc->background_option, oc->dpms_state);
 
         return oc;
 }
@@ -363,6 +368,14 @@ bool apply_output_config(struct output_config *oc, struct sway_output *output) {
                 sway_log(SWAY_DEBUG, "Set %s scale to %f", oc->name, oc->scale);
                 wlr_output_set_scale(wlr_output, oc->scale);
         }
+
+        if (oc && (oc->subpixel != WL_OUTPUT_SUBPIXEL_UNKNOWN || config->reloading)) {
+                sway_log(SWAY_DEBUG, "Set %s subpixel to %s", oc->name,
+                        sway_wl_output_subpixel_to_string(oc->subpixel));
+                wlr_output_set_subpixel(wlr_output, oc->subpixel);
+                output_damage_whole(output);
+        }
+
         if (oc && oc->transform >= 0) {
                 sway_log(SWAY_DEBUG, "Set %s transform to %d", oc->name, oc->transform);
                 wlr_output_set_transform(wlr_output, oc->transform);
@@ -424,6 +437,8 @@ static void default_output_config(struct output_config *oc,
         }
         oc->x = oc->y = -1;
         oc->scale = 1;
+        struct sway_output *output = wlr_output->data;
+        oc->subpixel = output->detected_subpixel;
         oc->transform = WL_OUTPUT_TRANSFORM_NORMAL;
         oc->dpms_state = DPMS_ON;
 }