enable rollback (#1378)

README.md

@@ -1,6 +1,6 @@
 # gopher64
 Gopher64 is a cross-platform N64 emulator. Some notable features:
-* Netplay
+* Rollback netplay
 * Homebrew support
 * Upscaling
 * CRT shader
@@ -42,7 +42,7 @@ Keys are mapped according to [these defaults](https://github.com/gopher64/gopher
 
 ## netplay
 
-Gopher64 supports P2P netplay (online play with others).
+Gopher64 supports P2P rollback netplay (online play with others).
 
 Please read the [guide](https://github.com/gopher64/gopher64/wiki/Netplay-Guide) before trying out netplay.
 

data/translations/de/LC_MESSAGES/gopher64.po

@@ -417,11 +417,11 @@ msgstr "Nachricht senden"
 #: src/ui/gui/netplay_wait.slint:104
 msgctxt "NetplayWait"
 msgid ""
-"Setting the input delay too low will cause the game to lag.\n"
+"Setting the input delay too low will cause frequent rollbacks.\n"
 "You can lower the input delay in-game by pressing Alt+[ and raise it with "
 "Alt+]."
 msgstr ""
-"Eine zu niedrige Eingabeverzögerung führt zu Ruckeln im Spiel.\n"
+"Eine zu niedrige Eingabeverzögerung führt zu häufigen Rollbacks.\n"
 "Sie können die Eingabeverzögerung im Spiel mit Alt+[ verringern und mit "
 "Alt+] erhöhen."
 

data/translations/es/LC_MESSAGES/gopher64.po

@@ -415,12 +415,12 @@ msgstr "Enviar mensaje"
 #: src/ui/gui/netplay_wait.slint:104
 msgctxt "NetplayWait"
 msgid ""
-"Setting the input delay too low will cause the game to lag.\n"
+"Setting the input delay too low will cause frequent rollbacks.\n"
 "You can lower the input delay in-game by pressing Alt+[ and raise it with "
 "Alt+]."
 msgstr ""
-"Configurar un retardo de entrada demasiado bajo hará que el juego se "
-"ralentice.\n"
+"Configurar un retardo de entrada demasiado bajo provocará rollbacks "
+"frecuentes.\n"
 "Puedes reducir el retardo de entrada en el juego pulsando Alt+[ y aumentarlo "
 "con Alt+]."
 

data/translations/fr/LC_MESSAGES/gopher64.po

@@ -417,11 +417,11 @@ msgstr "Envoyer"
 #: src/ui/gui/netplay_wait.slint:104
 msgctxt "NetplayWait"
 msgid ""
-"Setting the input delay too low will cause the game to lag.\n"
+"Setting the input delay too low will cause frequent rollbacks.\n"
 "You can lower the input delay in-game by pressing Alt+[ and raise it with "
 "Alt+]."
 msgstr ""
-"Régler le délai d'entrée trop bas provoquera des ralentissements.\n"
+"Régler le délai d'entrée trop bas provoquera des rollbacks fréquents.\n"
 "Vous pouvez diminuer le délai d'entrée en jeu avec Alt+[ et l'augmenter avec "
 "Alt+]."
 

data/translations/gopher64.pot

@@ -401,8 +401,8 @@ msgstr ""
 #: src/ui/gui/netplay_wait.slint:104
 msgctxt "NetplayWait"
 msgid ""
-"Setting the input delay too low will cause the game to lag.\nYou can lower "
-"the input delay in-game by pressing Alt+[ and raise it with Alt+]."
+"Setting the input delay too low will cause frequent rollbacks.\nYou can "
+"lower the input delay in-game by pressing Alt+[ and raise it with Alt+]."
 msgstr ""
 
 #: src/ui/gui/netplay_wait.slint:112

data/translations/ja/LC_MESSAGES/gopher64.po

@@ -414,11 +414,11 @@ msgstr "送信"
 #: src/ui/gui/netplay_wait.slint:104
 msgctxt "NetplayWait"
 msgid ""
-"Setting the input delay too low will cause the game to lag.\n"
+"Setting the input delay too low will cause frequent rollbacks.\n"
 "You can lower the input delay in-game by pressing Alt+[ and raise it with "
 "Alt+]."
 msgstr ""
-"入力遅延を低く設定しすぎるとゲームが遅延します。\n"
+"入力遅延を低く設定しすぎると頻繁にロールバックが発生します。\n"
 "Alt+[ でゲーム内の入力遅延を下げ、Alt+] で上げることができます。"
 
 #: src/ui/gui/netplay_wait.slint:112

data/translations/nl/LC_MESSAGES/gopher64.po

@@ -416,11 +416,11 @@ msgstr "Bericht verzenden"
 #: src/ui/gui/netplay_wait.slint:104
 msgctxt "NetplayWait"
 msgid ""
-"Setting the input delay too low will cause the game to lag.\n"
+"Setting the input delay too low will cause frequent rollbacks.\n"
 "You can lower the input delay in-game by pressing Alt+[ and raise it with "
 "Alt+]."
 msgstr ""
-"Een te lage invoervertraging zorgt ervoor dat het spel gaat haperen.\n"
+"Een te lage invoervertraging zorgt voor frequente rollbacks.\n"
 "Je kunt de invoervertraging in het spel verlagen met Alt+[ en verhogen met "
 "Alt+]."
 

data/translations/pt_BR/LC_MESSAGES/gopher64.po

@@ -417,11 +417,11 @@ msgstr "Enviar Mensagem"
 #: src/ui/gui/netplay_wait.slint:104
 msgctxt "NetplayWait"
 msgid ""
-"Setting the input delay too low will cause the game to lag.\n"
+"Setting the input delay too low will cause frequent rollbacks.\n"
 "You can lower the input delay in-game by pressing Alt+[ and raise it with "
 "Alt+]."
 msgstr ""
-"Definir o atraso de entrada muito baixo causará lag no jogo.\n"
+"Definir o atraso de entrada muito baixo causará rollbacks frequentes.\n"
 "Você pode diminuir o atraso de entrada no jogo pressionando Alt+[ e aumentá-"
 "lo com Alt+]."
 

data/translations/ru/LC_MESSAGES/gopher64.po

@@ -416,11 +416,11 @@ msgstr "Отправить сообщение"
 #: src/ui/gui/netplay_wait.slint:104
 msgctxt "NetplayWait"
 msgid ""
-"Setting the input delay too low will cause the game to lag.\n"
+"Setting the input delay too low will cause frequent rollbacks.\n"
 "You can lower the input delay in-game by pressing Alt+[ and raise it with "
 "Alt+]."
 msgstr ""
-"Слишком низкая задержка ввода вызовет лаги в игре.\n"
+"Слишком низкая задержка ввода вызовет частые откаты.\n"
 "Вы можете уменьшить задержку ввода в игре, нажав Alt+[, и увеличить её с "
 "помощью Alt+]."
 

src/netplay.rs

@@ -107,7 +107,6 @@ fn process_reliable_messages(netplay: &mut Netplay) {
                     .messages
                     .insert(decoded_message.name, decoded_message.data);
                 netplay.incoming_message.clear();
-                check_input_delay(netplay);
                 check_disconnect(netplay);
             }
         }
@@ -203,20 +202,11 @@ pub fn receive_save(netplay: &mut Netplay, save_type: &str, save_data: &mut Vec<
     *save_data = message;
 }
 
-pub fn send_input_delay(netplay: &mut Netplay, input_delay: usize) {
+pub fn change_input_delay(netplay: &mut Netplay, input_delay: usize) {
     if !(1..=MAX_PREDICTION_WINDOW).contains(&input_delay) {
         return;
     }
 
-    let message = NetplayMessage {
-        name: "input_delay".to_string(),
-        data: (input_delay as u64).to_be_bytes().to_vec(),
-    };
-    send_message(netplay, message);
-    change_input_delay(netplay, input_delay);
-}
-
-fn change_input_delay(netplay: &mut Netplay, input_delay: usize) {
     netplay.input_delay = input_delay;
     for handle in netplay.session.local_player_handles() {
         if let Err(e) = netplay.session.set_input_delay(handle, input_delay) {
@@ -230,15 +220,6 @@ fn change_input_delay(netplay: &mut Netplay, input_delay: usize) {
     }
 }
 
-fn check_input_delay(netplay: &mut Netplay) {
-    if let Some(data) = netplay.messages.remove("input_delay") {
-        let input_delay = u64::from_be_bytes(data.try_into().unwrap()) as usize;
-        if input_delay != netplay.input_delay {
-            change_input_delay(netplay, input_delay);
-        }
-    }
-}
-
 fn check_disconnect(netplay: &mut Netplay) {
     if !netplay.disconnected && netplay.messages.remove("disconnect").is_some() {
         netplay.disconnected = true;
@@ -272,7 +253,7 @@ pub fn process_requests(
         if let Some(request) = device.netplay.as_mut().unwrap().requests.pop_front() {
             match request {
                 ggrs::GgrsRequest::SaveGameState { cell, frame } => {
-                    //savestates::create_savestate(device, true, Some(frame));
+                    savestates::create_savestate(device, true, Some(frame));
 
                     let mut hasher = sha2::Sha256::new();
                     for reg in device.cpu.cop0.regs.as_ref() {
@@ -341,26 +322,13 @@ fn process_netplay(device: &mut device::Device) {
 
 fn advance_frame(device: &mut device::Device) {
     let netplay = device.netplay.as_mut().unwrap();
-    let local_input = if netplay.session.current_frame() > netplay.session.max_prediction() as i32 {
-        ui::input::get(&mut device.ui, 0)
-    } else {
-        //workaround for disabled rollback
-        ui::input::InputData::default()
-    };
+    let local_input = ui::input::get(&mut device.ui, 0);
     let local_handle = *netplay.session.local_player_handles().first().unwrap();
     netplay
         .session
         .add_local_input(local_handle, local_input)
         .unwrap();
 
-    // avoid rollback
-    while !netplay.disconnected
-        && netplay.session.current_frame() > netplay.session.confirmed_frame()
-        && netplay.session.confirmed_frame() != ggrs::NULL_FRAME
-    {
-        poll_clients(netplay);
-    }
-
     if netplay.disconnected {
         netplay.requests.push_back(ggrs::GgrsRequest::AdvanceFrame {
             inputs: vec![
@@ -503,6 +471,7 @@ pub fn init(
         .with_num_players(netplay_config.number_of_players)
         .unwrap()
         .with_input_delay(netplay_config.input_delay)
+        .with_sparse_saving_mode(true)
         .with_fps(if pal { 50 } else { 60 })
         .unwrap()
         .with_desync_detection_mode(ggrs::DesyncDetection::On { interval: 60 })

src/ui/gui/netplay_wait.slint

@@ -101,12 +101,12 @@ export component NetplayWait inherits Page {
                 }
 
                 Text {
-                    text: NetplayData.player_name == NetplayWaitData.players[0] ? @tr("Setting the input delay too low will cause the game to lag.\nYou can lower the input delay in-game by pressing Alt+[ and raise it with Alt+].") : NetplayWaitData.motd;
+                    text: @tr("Setting the input delay too low will cause frequent rollbacks.\nYou can lower the input delay in-game by pressing Alt+[ and raise it with Alt+].");
                     horizontal-alignment: center;
                     wrap: word-wrap;
                 }
 
-                if NetplayData.player_name == NetplayWaitData.players[0]: HorizontalBox {
+                HorizontalBox {
                     alignment: center;
                     Text {
                         text: @tr("Local Input Delay:");

src/ui/netplay.rs

@@ -799,14 +799,21 @@ fn setup_wait_window(
                                 .upgrade_in_event_loop(move |handle| {
                                     let player_name = handle.get_netplay_player_name();
                                     let players = handle.get_netplay_players();
-                                    let input_delay = response
-                                        .sessions
-                                        .iter()
-                                        .next()
-                                        .unwrap()
-                                        .1
-                                        .input_delay
-                                        .unwrap();
+                                    // Input delay is per-player: use our own choice, falling back
+                                    // to the host's if our recommendation hasn't been calculated yet.
+                                    let local_input_delay = handle.get_netplay_input_delay();
+                                    let input_delay = if local_input_delay > 0 {
+                                        local_input_delay as usize
+                                    } else {
+                                        response
+                                            .sessions
+                                            .iter()
+                                            .next()
+                                            .unwrap()
+                                            .1
+                                            .input_delay
+                                            .unwrap()
+                                    };
                                     let player_number =
                                         players.iter().position(|x| x == player_name).unwrap();
                                     run_rom(

src/ui/video.rs

@@ -271,13 +271,11 @@ pub fn check_callback(device: &mut device::Device) -> (bool, bool) {
         ui::audio::raise_audio_volume(&mut device.ui);
     }
 
-    if let Some(netplay) = &mut device.netplay
-        && netplay.player_number == 0
-    {
+    if let Some(netplay) = &mut device.netplay {
         if callback.decrease_input_delay {
-            netplay::send_input_delay(netplay, netplay.input_delay - 1);
+            netplay::change_input_delay(netplay, netplay.input_delay.saturating_sub(1));
         } else if callback.increase_input_delay {
-            netplay::send_input_delay(netplay, netplay.input_delay + 1);
+            netplay::change_input_delay(netplay, netplay.input_delay + 1);
         }
     }
     (speed_limiter_toggled, callback.paused)