Add features.hdr to output IPC response

4 files changed, 33 insertions, 19 deletions

diff --git a/include/sway/output.h b/include/sway/output.h
index 06f8bac2..787527ee 100644
--- a/include/sway/output.h
+++ b/include/sway/output.h
@@ -131,6 +131,8 @@ struct sway_container *output_find_container(struct sway_output *output,
 
 void output_get_box(struct sway_output *output, struct wlr_box *box);
 
+bool output_supports_hdr(struct wlr_output *output, const char **unsupported_reason_ptr);
+
 enum sway_container_layout output_get_default_layout(
 		struct sway_output *output);
 
diff --git a/sway/config/output.c b/sway/config/output.c
index ab2cd200..2e3c05db 100644
--- a/sway/config/output.c
+++ b/sway/config/output.c
@@ -348,22 +348,26 @@ static void set_modeline(struct wlr_output *output,
 #endif
 }
 
+bool output_supports_hdr(struct wlr_output *output, const char **unsupported_reason_ptr) {
+	const char *unsupported_reason = NULL;
+	if (!(output->supported_primaries & WLR_COLOR_NAMED_PRIMARIES_BT2020)) {
+		unsupported_reason = "BT2020 primaries not supported by output";
+	} else if (!(output->supported_transfer_functions & WLR_COLOR_TRANSFER_FUNCTION_ST2084_PQ)) {
+		unsupported_reason = "PQ transfer function not supported by output";
+	} else if (!server.renderer->features.output_color_transform) {
+		unsupported_reason = "renderer doesn't support output color transforms";
+	}
+	if (unsupported_reason_ptr != NULL) {
+		*unsupported_reason_ptr = unsupported_reason;
+	}
+	return unsupported_reason == NULL;
+}
+
 static void set_hdr(struct wlr_output *output, struct wlr_output_state *pending, bool enabled) {
-	enum wlr_color_named_primaries primaries = WLR_COLOR_NAMED_PRIMARIES_BT2020;
-	enum wlr_color_transfer_function tf = WLR_COLOR_TRANSFER_FUNCTION_ST2084_PQ;
-	if (enabled && !(output->supported_primaries & primaries)) {
-		sway_log(SWAY_ERROR, "Cannot enable HDR on output %s: BT2020 primaries not supported by output",
-			output->name);
-		enabled = false;
-	}
-	if (enabled && !(output->supported_transfer_functions & WLR_COLOR_TRANSFER_FUNCTION_ST2084_PQ)) {
-		sway_log(SWAY_ERROR, "Cannot enable HDR on output %s: PQ transfer function not supported by output",
-			output->name);
-		enabled = false;
-	}
-	if (enabled && !server.renderer->features.output_color_transform) {
-		sway_log(SWAY_ERROR, "Cannot enable HDR on output %s: renderer doesn't support output color transforms",
-			output->name);
+	const char *unsupported_reason = NULL;
+	if (!output_supports_hdr(output, &unsupported_reason)) {
+		sway_log(SWAY_ERROR, "Cannot enable HDR on output %s: %s",
+			output->name, unsupported_reason);
 		enabled = false;
 	}
 
@@ -377,8 +381,8 @@ static void set_hdr(struct wlr_output *output, struct wlr_output_state *pending,
 
 	sway_log(SWAY_DEBUG, "Enabling HDR on output %s", output->name);
 	const struct wlr_output_image_description image_desc = {
-		.primaries = primaries,
-		.transfer_function = tf,
+		.primaries = WLR_COLOR_NAMED_PRIMARIES_BT2020,
+		.transfer_function = WLR_COLOR_TRANSFER_FUNCTION_ST2084_PQ,
 	};
 	wlr_output_state_set_image_description(pending, &image_desc);
 }
diff --git a/sway/ipc-json.c b/sway/ipc-json.c
index 30ed2430..3933f3ef 100644
--- a/sway/ipc-json.c
+++ b/sway/ipc-json.c
@@ -323,6 +323,8 @@ static void ipc_json_describe_wlr_output(struct wlr_output *wlr_output, json_obj
 	json_object_object_add(features_object, "adaptive_sync",
 		json_object_new_boolean(wlr_output->adaptive_sync_supported ||
 			wlr_output->adaptive_sync_status ==  WLR_OUTPUT_ADAPTIVE_SYNC_ENABLED));
+	json_object_object_add(features_object, "hdr",
+		json_object_new_boolean(output_supports_hdr(wlr_output, NULL)));
 	json_object_object_add(object, "features", features_object);
 }
 
diff --git a/swaymsg/main.c b/swaymsg/main.c
index 1c6e807c..d58f29e2 100644
--- a/swaymsg/main.c
+++ b/swaymsg/main.c
@@ -212,9 +212,10 @@ static void pretty_print_output(json_object *o) {
 	json_object_object_get_ex(current_mode, "width", &width);
 	json_object_object_get_ex(current_mode, "height", &height);
 	json_object_object_get_ex(current_mode, "refresh", &refresh);
-	json_object *features, *features_adaptive_sync;
+	json_object *features, *features_adaptive_sync, *features_hdr;
 	json_object_object_get_ex(o, "features", &features);
 	json_object_object_get_ex(features, "adaptive_sync", &features_adaptive_sync);
+	json_object_object_get_ex(features, "hdr", &features_hdr);
 
 	if (json_object_get_boolean(non_desktop)) {
 		printf(
@@ -263,7 +264,12 @@ static void pretty_print_output(json_object *o) {
 
 		printf("  Allow tearing: %s\n",
 			json_object_get_boolean(allow_tearing) ? "yes" : "no");
-		printf("  HDR: %s\n", json_object_get_boolean(hdr) ? "on" : "off");
+
+		const char *hdr_str = "unsupported";
+		if (json_object_get_boolean(features_hdr)) {
+			hdr_str = json_object_get_boolean(hdr) ? "on" : "off";
+		}
+		printf("  HDR: %s\n", hdr_str);
 	} else {
 		printf(
 			"Output %s '%s %s %s' (disabled)\n",