From 3749141fee842b897627b003f88aab9efc9bc021 Mon Sep 17 00:00:00 2001
From: "Steinar H. Gunderson" <sgunderson@bigfoot.com>
Date: Mon, 28 Dec 2020 01:08:25 +0100
Subject: [PATCH] Add some special early output when the position changes.

---
 config.pm     |  1 +
 remoteglot.pl | 34 ++++++++++++++++++++++++++++------
 2 files changed, 29 insertions(+), 6 deletions(-)

diff --git a/config.pm b/config.pm
index 44ed56b..7f7e23c 100644
--- a/config.pm
+++ b/config.pm
@@ -58,6 +58,7 @@ our %engine2_config = (
 our $engine2_grpc_backend = undef;  # Not used by us, but will be communicated to serve-analysis.js.
 
 our $update_max_interval = 1.0;
+our $update_force_after_move = 0.2;
 our @masters = (
 	'Sesse',
 );
diff --git a/remoteglot.pl b/remoteglot.pl
index 9d611c0..455d730 100755
--- a/remoteglot.pl
+++ b/remoteglot.pl
@@ -76,6 +76,10 @@ my $last_move;
 my $last_text = '';
 my ($pos_calculating, $pos_calculating_second_engine);
 
+# If not undef, we've started calculating this position but haven't ever given out
+# any analysis for it, so we're on a forced timer to do so.
+my $pos_calculating_started = undef;
+
 setoptions($engine, \%remoteglotconf::engine_config);
 uciprint($engine, "ucinewgame");
 
@@ -388,12 +392,22 @@ sub handle_position {
 		# the position.)
 		#
 		# Do not output anything new to the main analysis; that's
-		# going to be obsolete really soon.
+		# going to be obsolete really soon. (Exception: If we've never
+		# output anything for this move, ie., it didn't hit the 200ms
+		# limit, spit it out to the user anyway. It's probably a really
+		# fast blitz game or something, and it's good to show the moves
+		# as they come in even without great analysis.)
 		$pos_calculating->{'white_clock'} = $pos->{'white_clock'};
 		$pos_calculating->{'black_clock'} = $pos->{'black_clock'};
 		delete $pos_calculating->{'white_clock_target'};
 		delete $pos_calculating->{'black_clock_target'};
-		output_json(1);
+
+		if (defined($pos_calculating_started)) {
+			output_json(0);
+		} else {
+			output_json(1);
+		}
+		$pos_calculating_started = [Time::HiRes::gettimeofday];
 
 		# Ask the engine to stop; we will throw away its data until it
 		# sends us "bestmove", signaling the end of it.
@@ -411,6 +425,7 @@ sub handle_position {
 	uciprint($engine, "position fen " . $pos->fen());
 	uciprint($engine, "go infinite");
 	$pos_calculating = $pos;
+	$pos_calculating_started = [Time::HiRes::gettimeofday];
 
 	if (defined($engine2)) {
 		if (defined($pos_calculating_second_engine)) {
@@ -634,15 +649,22 @@ sub output {
 	return if (!defined($pos_calculating));
 
 	# Don't update too often.
-	my $age = Time::HiRes::tv_interval($latest_update);
-	if ($age < $remoteglotconf::update_max_interval) {
-		my $wait = $remoteglotconf::update_max_interval + 0.01 - $age;
-		$output_timer = AnyEvent->timer(after => $wait, cb => \&output);
+	my $wait = $remoteglotconf::update_max_interval - Time::HiRes::tv_interval($latest_update);
+	my $new_pos_wait = defined($pos_calculating_started) ?
+		$remoteglotconf::update_force_after_move - Time::HiRes::tv_interval($pos_calculating_started)
+		: 10000.0;
+	$wait = $new_pos_wait if ($new_pos_wait < $wait);
+	if ($wait > 0.0) {
+		$output_timer = AnyEvent->timer(after => $wait + 0.01, cb => \&output);
 		return;
 	}
 	
 	my $info = $engine->{'info'};
 
+	# We're outputting something for this position now, so the special handling
+	# for new positions is off.
+	undef $pos_calculating_started;
+	
 	#
 	# If we have tablebase data from a previous lookup, replace the
 	# engine data with the data from the tablebase.
-- 
2.39.2