#151 add VRR_OFF hint on adaptive sync failure (#152)

* #151 add VRR_OFF hint on adaptive sync failure

src/layout.c

@@ -323,6 +323,14 @@ void apply(void) {
 	slist_free(&heads_changing);
 }
 
+void report_adaptive_sync_fail(struct Head *head) {
+	log_info("\n%s:", head->name);
+	log_info("  Cannot enable VRR: this display or compositor may not support it.");
+	log_info("  To speed things up you can disable VRR for this display by adding the following or similar to your cfg.yaml");
+	log_info("  VRR_OFF:");
+	log_info("    - '%s'", head->model ? head->model : "monitor description");
+}
+
 void handle_success(void) {
 	if (head_changing_mode) {
 
@@ -338,7 +346,7 @@ void handle_success(void) {
 
 		// sway reports adaptive sync failure as success
 		if (head_current_adaptive_sync_not_desired(head)) {
-			log_info("\n%s: Cannot enable VRR, display or compositor may not support it.", head->name);
+			report_adaptive_sync_fail(head);
 			head->adaptive_sync_failed = true;
 			return;
 		}
@@ -365,7 +373,7 @@ void handle_failure(void) {
 	} else if (head_changing_adaptive_sync && head_current_adaptive_sync_not_desired(head_changing_adaptive_sync)) {
 
 		// river reports adaptive sync failure as failure
-		log_info("\n%s: Cannot enable VRR, display or compositor may not support it.", head_changing_adaptive_sync->name);
+		report_adaptive_sync_fail(head_changing_adaptive_sync);
 		head_changing_adaptive_sync->adaptive_sync_failed = true;
 
 		head_changing_adaptive_sync = NULL;

tst/tst-layout.c

@@ -613,14 +613,19 @@ void handle_success__head_changing_adaptive_sync(void **state) {
 void handle_success__head_changing_adaptive_sync_fail(void **state) {
 	struct Head head = {
 		.name = "head",
+		.model = NULL, // fall back to placeholder
 		.desired.adaptive_sync = ZWLR_OUTPUT_HEAD_V1_ADAPTIVE_SYNC_STATE_ENABLED,
 		.current.adaptive_sync = ZWLR_OUTPUT_HEAD_V1_ADAPTIVE_SYNC_STATE_DISABLED,
 	};
 	head_changing_adaptive_sync = &head;
 
 	handle_success();
 
-	assert_log(INFO, "\nhead: Cannot enable VRR, display or compositor may not support it.\n");
+	assert_log(INFO, "\nhead:\n"
+			"  Cannot enable VRR: this display or compositor may not support it.\n"
+			"  To speed things up you can disable VRR for this display by adding the following or similar to your cfg.yaml\n"
+			"  VRR_OFF:\n"
+			"    - 'monitor description'\n");
 
 	assert_null(head_changing_adaptive_sync);
 	assert_true(head.adaptive_sync_failed);
@@ -677,14 +682,19 @@ void handle_failure__mode(void **state) {
 void handle_failure__adaptive_sync(void **state) {
 	struct Head head = {
 		.name = "nam",
+		.model = "mod",
 		.current.adaptive_sync = ZWLR_OUTPUT_HEAD_V1_ADAPTIVE_SYNC_STATE_DISABLED,
 		.desired.adaptive_sync = ZWLR_OUTPUT_HEAD_V1_ADAPTIVE_SYNC_STATE_ENABLED,
 	};
 	head_changing_adaptive_sync = &head;
 
 	handle_failure();
 
-	assert_log(INFO, "\nnam: Cannot enable VRR, display or compositor may not support it.\n");
+	assert_log(INFO, "\nnam:\n"
+			"  Cannot enable VRR: this display or compositor may not support it.\n"
+			"  To speed things up you can disable VRR for this display by adding the following or similar to your cfg.yaml\n"
+			"  VRR_OFF:\n"
+			"    - 'mod'\n");
 
 	assert_null(head_changing_adaptive_sync);