Menus: Horizon-style options screen, pause polish, screenshots

Options open as the launcher's Settings page: a sidebar with the sliding
selection (Video, Audio, Controls, Accessibility, Language, Chat, Interface)
and rows with a switch, slider or value button per option
(options_horizon.rs; new sections or rows slot into SECTIONS). Key binds,
the language list and resource packs open vanilla's pages. Interface holds
Menu style (Horizon / Classic). The pause menu hides the in-game HUD over the
blurred world. Scripted and frame-limited runs default to Classic, so the
harnesses see vanilla's screens.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

Cargo.lock

@@ -681,12 +681,14 @@ dependencies = [
 name = "horizon-client"
 version = "0.1.0"
 dependencies = [
+ "ab_glyph",
  "bytemuck",
  "cpal",
  "glam",
  "horizon-assets",
  "horizon-core",
  "horizon-protocol",
+ "horizon-theme",
  "horizon-world",
  "miniz_oxide 0.8.9",
  "png",
@@ -713,6 +715,10 @@ dependencies = [
  "serde_json",
 ]
 
+[[package]]
+name = "horizon-theme"
+version = "0.1.0"
+
 [[package]]
 name = "horizon-world"
 version = "0.1.0"

Cargo.toml

@@ -1,6 +1,6 @@
 [workspace]
 exclude = ["launcher"]
-members = ["crates/horizon-core", "crates/horizon-world", "crates/voxel-kernels", "crates/horizon-client", "crates/horizon-assets", "crates/horizon-protocol"]
+members = ["crates/horizon-core", "crates/horizon-world", "crates/voxel-kernels", "crates/horizon-client", "crates/horizon-assets", "crates/horizon-protocol", "crates/horizon-theme"]
 resolver = "2"
 
 [workspace.package]

crates/horizon-client/Cargo.toml

@@ -22,6 +22,8 @@ serde_json = { version = "1.0.151", features = ["raw_value"] }
 cpal = "0.16"
 symphonia = { version = "0.5", default-features = false, features = ["ogg", "vorbis"] }
 miniz_oxide = "0.8"
+ab_glyph = "0.2.32"
+horizon-theme = { path = "../horizon-theme" }
 
 [features]
 # Records the call sites of mob random draws (`mob_ai_probe` traces).

crates/horizon-client/src/front.rs

@@ -0,0 +1,987 @@
+//! The front-end screens in Horizon's menu style (`ui_theme`), laid out like
+//! the launcher: a 200-wide sidebar with the sliding selection (Home,
+//! Singleplayer, Multiplayer, Options), content pages with a page header,
+//! settings rows and 1px dividers, and the launcher's opening (the wordmark,
+//! then the interface). They drive the same state as the classic layouts in
+//! `title` and `multiplayer`; only drawing and hit testing differ. The pause
+//! menu's Horizon layout is `pause`, below.
+use crate::{
+    hud::{HudAtlas, HudBatch},
+    multiplayer::{Outcome, Ping, Screen},
+    title::{Action, Mode, Title, list_worlds},
+    ui_theme::{
+        self as t, BODY, CONTROL, CONTROL_LARGE, Face, Kind, SIDEBAR, SMALL, Ui, color, id,
+    },
+};
+use std::time::Instant;
+
+const NAV: u64 = id("title.nav", 0);
+const QUIT: u64 = id("title.quit", 0);
+const PLAY: u64 = id("home.play", 0);
+const MULTIPLAYER: u64 = id("home.multiplayer", 0);
+const RESUME: u64 = id("home.resume", 0);
+const BACK: u64 = id("front.back", 0);
+const PLAY_WORLD: u64 = id("worlds.play", 0);
+const CREATE: u64 = id("worlds.create", 0);
+const WORLD: u64 = id("worlds.row", 0);
+const NAME: u64 = id("create.name", 0);
+const SEED: u64 = id("create.seed", 0);
+const MODE: u64 = id("create.mode", 0);
+const MAKE: u64 = id("create.make", 0);
+const SERVER: u64 = id("mp.row", 0);
+const JOIN: u64 = id("mp.join", 0);
+const DIRECT: u64 = id("mp.direct", 0);
+const ADD: u64 = id("mp.add", 0);
+const EDIT: u64 = id("mp.edit", 0);
+const DELETE: u64 = id("mp.delete", 0);
+const REFRESH: u64 = id("mp.refresh", 0);
+const FIELD_A: u64 = id("mp.field", 0);
+const FIELD_B: u64 = id("mp.field", 1);
+const DONE: u64 = id("mp.done", 0);
+
+/// The launcher's opening (`launcher/src/main.rs`): the wordmark holds over
+/// the backdrop, then the interface comes in. A click or a key skips ahead.
+#[derive(Clone, Copy, Debug)]
+pub struct Opening {
+    started: Instant,
+    reveal: Option<Instant>,
+}
+impl Opening {
+    pub fn new() -> Self {
+        Self {
+            started: Instant::now(),
+            reveal: None,
+        }
+    }
+    /// The reveal's progress, 0 to 1; `ready` says the backdrop is showing.
+    fn phase(&mut self, ready: bool) -> f32 {
+        let held = self.started.elapsed();
+        if self.reveal.is_none()
+            && ((held >= horizon_theme::OPENING_HOLD && ready)
+                || held >= horizon_theme::OPENING_MAX)
+        {
+            self.reveal = Some(Instant::now());
+        }
+        self.reveal.map_or(0.0, |at| {
+            at.elapsed().as_secs_f32() / horizon_theme::OPENING_REVEAL.as_secs_f32()
+        })
+    }
+    pub fn skip(&mut self) {
+        self.reveal.get_or_insert_with(Instant::now);
+    }
+}
+impl Default for Opening {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+/// Which sidebar item a mode belongs to.
+fn page(mode: &Mode) -> usize {
+    match mode {
+        Mode::Main => 0,
+        Mode::Select { .. } | Mode::Create { .. } => 1,
+        Mode::Multiplayer(_) => 2,
+    }
+}
+const PAGES: [&str; 4] = ["Home", "Singleplayer", "Multiplayer", "Options"];
+
+impl Title {
+    /// Horizon's layout for every title mode. `backdrop` is how much of the
+    /// live backdrop is visible (0 shows the plain cold background).
+    pub fn draw_horizon(&self, ui: &mut Ui, backdrop: f32) {
+        let reveal = self.opening_phase(backdrop >= 1.0);
+        if backdrop < 1.0 {
+            ui.cold_background(1.0 - backdrop);
+        }
+        let shade = t::ease_out_cubic(reveal);
+        let veil = if matches!(self.mode, Mode::Main) {
+            0.42
+        } else {
+            0.66
+        };
+        ui.atmosphere(veil * shade, shade);
+        let side = t::ease_out_cubic((reveal - 0.2) / 0.7);
+        let main = t::ease_out_cubic((reveal - 0.35) / 0.65);
+
+        // The sidebar slides in from the left.
+        ui.opacity = side;
+        ui.offset = (-16.0 * (1.0 - side), 0.0);
+        if side > 0.0 {
+            self.sidebar(ui);
+        }
+        // The content rises; each new page fades in and rises 8 over MOVE.
+        let entered = self.entered();
+        let p = t::ease_out_quint(entered.elapsed().as_secs_f32() / t::move_());
+        ui.opacity = main * p;
+        ui.offset = (0.0, 16.0 * (1.0 - main) + 8.0 * (1.0 - p));
+        if main > 0.0 {
+            let x = SIDEBAR + 48.0;
+            let w = (ui.w - x - 48.0).min(760.0);
+            match &self.mode {
+                Mode::Main => self.home(ui, x, w),
+                Mode::Select { worlds, selected } => worlds_page(ui, x, w, worlds, *selected),
+                Mode::Create {
+                    name,
+                    seed,
+                    creative,
+                    focus,
+                } => {
+                    let caret = (self.started.elapsed().as_millis() / 500).is_multiple_of(2);
+                    create_page(ui, x, w, name, seed, *creative, *focus, caret);
+                }
+                Mode::Multiplayer(screen) => {
+                    let caret = (self.started.elapsed().as_millis() / 500).is_multiple_of(2);
+                    multiplayer_page(ui, x, w, screen, caret);
+                }
+            }
+        }
+        ui.opacity = 1.0;
+        ui.offset = (0.0, 0.0);
+        if reveal < 1.0 {
+            // The wordmark rises and fades as the interface comes in.
+            let word = 1.0 - t::ease_out_cubic(reveal / 0.6);
+            ui.opacity = word;
+            let tw = ui.measure(Face::Display, t::WORDMARK, "Horizon");
+            let line = (t::WORDMARK * 1.2).round();
+            ui.text_line(
+                Face::Display,
+                t::WORDMARK,
+                line,
+                ((ui.w - tw) / 2.0).round(),
+                (ui.h - line) / 2.0 - 28.0 * (1.0 - word),
+                color::WHITE,
+                "Horizon",
+            );
+            ui.opacity = 1.0;
+        }
+    }
+    fn opening_phase(&self, ready: bool) -> f32 {
+        let mut opening = self.opening.get();
+        let phase = opening.as_mut().map_or(1.0, |o| o.phase(ready));
+        self.opening.set(opening.filter(|_| phase < 1.0));
+        phase.min(1.0)
+    }
+    /// A click or key during the opening jumps to the reveal; true if it did.
+    pub fn skip_opening(&self) -> bool {
+        let mut opening = self.opening.get();
+        let skipped = opening.as_mut().is_some_and(|o| {
+            let holding = o.reveal.is_none();
+            o.skip();
+            holding
+        });
+        self.opening.set(opening);
+        skipped
+    }
+    fn sidebar(&self, ui: &mut Ui) {
+        let h = ui.h;
+        ui.fill(0.0, 0.0, SIDEBAR, h, color::with_alpha(color::SIDEBAR, 0.8));
+        ui.vline(SIDEBAR - 1.0, 0.0, h, color::BORDER);
+        ui.text_line(
+            Face::Display,
+            22.0,
+            30.0,
+            22.0,
+            16.0,
+            color::TEXT,
+            "Horizon",
+        );
+        ui.sidebar_list(NAV, 12.0, 66.0, SIDEBAR - 24.0, &PAGES, page(&self.mode));
+        let qy = h - 12.0 - 18.0 - 12.0 - CONTROL;
+        let hover = ui.interact(QUIT, 12.0, qy, SIDEBAR - 24.0, CONTROL, true);
+        ui.rounded(
+            12.0,
+            qy,
+            SIDEBAR - 24.0,
+            CONTROL,
+            t::RADIUS,
+            color::with_alpha(color::HOVER, 0.7 * hover),
+        );
+        ui.text_line(
+            Face::Regular,
+            BODY,
+            CONTROL,
+            22.0,
+            qy,
+            color::mix(color::MUTED, color::TEXT, hover),
+            "Quit game",
+        );
+        ui.text(
+            Face::Regular,
+            SMALL,
+            22.0,
+            h - 12.0 - 18.0,
+            color::FAINT,
+            "Horizon 26.3",
+        );
+    }
+    /// Home: the launcher's Play page over the backdrop.
+    fn home(&self, ui: &mut Ui, x: f32, w: f32) {
+        let mut y = 36.0 + 28.0;
+        ui.text(
+            Face::Medium,
+            SMALL,
+            x,
+            y,
+            color::FAINT,
+            "Minecraft 26.3  ·  Java Edition, rewritten in Rust",
+        );
+        y += 22.0;
+        ui.text_line(Face::Display, t::HERO, 58.0, x, y, color::TEXT, "Horizon");
+        y += 58.0 + 12.0;
+        ui.text(
+            Face::Regular,
+            t::LARGE,
+            x,
+            y,
+            color::MUTED,
+            "The world you know, rebuilt from the ground up.",
+        );
+        y += 22.0 + 24.0;
+        let pw = ui.button_width("Singleplayer", true).max(120.0);
+        ui.button(
+            PLAY,
+            [x, y, pw, CONTROL_LARGE],
+            "Singleplayer",
+            Kind::Primary,
+            true,
+        );
+        let mw = ui.button_width("Multiplayer", true);
+        ui.button(
+            MULTIPLAYER,
+            [x + pw + 8.0, y, mw, CONTROL_LARGE],
+            "Multiplayer",
+            Kind::Secondary,
+            true,
+        );
+        y += CONTROL_LARGE + 24.0;
+        ui.divider(x, y, w);
+        let worlds = self.recent_worlds();
+        let last = worlds.first();
+        let value = last.map_or("None yet".to_owned(), |l| {
+            let secs = l
+                .modified
+                .duration_since(std::time::UNIX_EPOCH)
+                .map_or(0, |d| d.as_secs());
+            format!("{}  ·  {}", l.name, crate::title::date_label(secs))
+        });
+        let rh = ui.row(x, y, "Last played", &value, w - t::ROW_LABEL - 120.0);
+        if last.is_some() {
+            let bw = ui.button_width("Resume", false);
+            ui.button(
+                RESUME,
+                [x + w - bw, y + (rh - CONTROL) / 2.0, bw, CONTROL],
+                "Resume",
+                Kind::Secondary,
+                true,
+            );
+        }
+        y += rh;
+        ui.divider(x, y, w);
+        let count = match worlds.len() {
+            1 => "1 world".to_owned(),
+            n => format!("{n} worlds"),
+        };
+        y += ui.row(x, y, "Saves", &count, w - t::ROW_LABEL - 16.0);
+        ui.divider(x, y, w);
+        let note = "Not affiliated with Mojang or Microsoft";
+        ui.text(
+            Face::Regular,
+            SMALL,
+            x,
+            ui.h - 12.0 - 18.0,
+            color::FAINT,
+            note,
+        );
+    }
+    /// A click in Horizon's layout (`x`, `y` in GUI pixels).
+    pub fn click_horizon(
+        &mut self,
+        atlas: &HudAtlas,
+        batch: &mut HudBatch,
+        x: f32,
+        y: f32,
+    ) -> Action {
+        if self.skip_opening() {
+            return Action::None;
+        }
+        let hit = {
+            let mut ui = Ui::dry(atlas, batch, (x, y));
+            self.draw_horizon(&mut ui, 1.0);
+            ui.hit((x, y))
+        };
+        let Some(hit) = hit else {
+            if let Mode::Create { focus, .. } = &mut self.mode {
+                *focus = 2;
+            }
+            return Action::None;
+        };
+        let saves = self.saves.clone();
+        let select = |saves: &std::path::Path| Mode::Select {
+            worlds: list_worlds(saves),
+            selected: None,
+        };
+        match hit {
+            QUIT => return Action::Quit,
+            h if h == NAV => {
+                self.mode = Mode::Main;
+                return Action::None;
+            }
+            h if h == NAV + 1 => {
+                if !matches!(self.mode, Mode::Select { .. }) {
+                    self.mode = select(&saves);
+                }
+                return Action::None;
+            }
+            h if h == NAV + 2 => {
+                if !matches!(self.mode, Mode::Multiplayer(_)) {
+                    self.mode = Mode::Multiplayer(Screen::list(&saves));
+                }
+                return Action::None;
+            }
+            h if h == NAV + 3 => return Action::Options,
+            _ => {}
+        }
+        match &mut self.mode {
+            Mode::Main => match hit {
+                PLAY => self.mode = select(&saves),
+                MULTIPLAYER => self.mode = Mode::Multiplayer(Screen::list(&saves)),
+                RESUME => {
+                    if let Some(w) = list_worlds(&saves).into_iter().next() {
+                        return Action::Play { folder: w.folder };
+                    }
+                }
+                _ => {}
+            },
+            Mode::Select { worlds, selected } => match hit {
+                PLAY_WORLD => {
+                    if let Some(w) = selected.and_then(|i| worlds.get(i)) {
+                        return Action::Play {
+                            folder: w.folder.clone(),
+                        };
+                    }
+                }
+                CREATE => {
+                    self.mode = Mode::Create {
+                        name: "New World".into(),
+                        seed: String::new(),
+                        creative: false,
+                        focus: 0,
+                    }
+                }
+                h if (WORLD..WORLD + 10_000).contains(&h) => {
+                    let i = (h - WORLD) as usize;
+                    if *selected == Some(i) {
+                        return Action::Play {
+                            folder: worlds[i].folder.clone(),
+                        };
+                    }
+                    *selected = Some(i);
+                }
+                _ => {}
+            },
+            Mode::Create {
+                creative, focus, ..
+            } => match hit {
+                BACK => self.mode = select(&saves),
+                NAME => *focus = 0,
+                SEED => *focus = 1,
+                h if h == MODE || h == MODE + 1 => *creative = h == MODE + 1,
+                MAKE => return self.create_action(),
+                _ => {}
+            },
+            Mode::Multiplayer(screen) => {
+                let id = match hit {
+                    JOIN => Some(40),
+                    DIRECT => Some(41),
+                    ADD => Some(42),
+                    EDIT => Some(43),
+                    DELETE => Some(44),
+                    REFRESH => Some(45),
+                    BACK => Some(match screen {
+                        Screen::List { .. } => 46,
+                        Screen::Edit { .. } => 51,
+                        Screen::Direct { .. } => 53,
+                        Screen::Disconnected { .. } => 54,
+                    }),
+                    DONE => Some(match screen {
+                        Screen::Direct { .. } => 52,
+                        _ => 50,
+                    }),
+                    FIELD_A | FIELD_B => {
+                        if let Screen::Edit { focus, .. } = screen {
+                            *focus = u8::from(hit == FIELD_B);
+                        }
+                        None
+                    }
+                    h if (SERVER..SERVER + 10_000).contains(&h) => {
+                        let i = (h - SERVER) as usize;
+                        let again =
+                            matches!(screen, Screen::List { selected, .. } if *selected == Some(i));
+                        if again {
+                            if let Some(address) = screen.address_of(i) {
+                                return Action::Connect { address };
+                            }
+                        } else if let Screen::List { selected, .. } = screen {
+                            *selected = Some(i);
+                        }
+                        None
+                    }
+                    _ => None,
+                };
+                if let Some(id) = id {
+                    match screen.click(Some(id), 0.0, 0.0, (0.0, 0.0), &saves) {
+                        Outcome::Back => self.mode = Mode::Main,
+                        Outcome::Connect(address) => return Action::Connect { address },
+                        Outcome::None => {}
+                    }
+                }
+            }
+        }
+        Action::None
+    }
+}
+
+/// The page header plus a row of actions under it; returns the y below.
+fn header(ui: &mut Ui, x: f32, title: &str, description: &str) -> f32 {
+    let y = 36.0;
+    y + ui.page_header(x, y, title, description) + 24.0
+}
+/// Actions laid out right to left from `right`; returns the left edge.
+fn actions_right(ui: &mut Ui, right: f32, y: f32, items: &[(u64, &str, Kind, bool)]) -> f32 {
+    let mut rx = right;
+    for &(bid, label, kind, on) in items {
+        let large = kind == Kind::Primary;
+        let (bw, bh) = if large {
+            (ui.button_width(label, true).max(120.0), CONTROL_LARGE)
+        } else {
+            (ui.button_width(label, false), CONTROL)
+        };
+        rx -= bw;
+        ui.button(
+            bid,
+            [rx, y + (CONTROL_LARGE - bh) / 2.0, bw, bh],
+            label,
+            kind,
+            on,
+        );
+        rx -= 8.0;
+    }
+    rx
+}
+/// A selectable list row: the launcher's row look with a hover layer and
+/// the raised selection with its 1px border. Returns the row height.
+#[allow(clippy::too_many_arguments)]
+fn list_row(
+    ui: &mut Ui,
+    rid: u64,
+    x: f32,
+    y: f32,
+    w: f32,
+    selected: bool,
+    title: &str,
+    meta: &str,
+    right: &str,
+    dot: Option<u32>,
+) -> f32 {
+    let h = 60.0;
+    let hover = ui.interact(rid, x - 12.0, y + 2.0, w + 24.0, h - 4.0, true);
+    let sel = ui.tween(rid ^ 0x5e1ec7, if selected { 1.0 } else { 0.0 }, t::quick());
+    ui.rounded(
+        x - 12.0,
+        y + 4.0,
+        w + 24.0,
+        h - 8.0,
+        t::RADIUS,
+        color::with_alpha(color::HOVER, 0.7 * hover),
+    );
+    ui.rounded(
+        x - 12.0,
+        y + 4.0,
+        w + 24.0,
+        h - 8.0,
+        t::RADIUS,
+        color::with_alpha(color::RAISED, sel),
+    );
+    ui.border(
+        x - 12.0,
+        y + 4.0,
+        w + 24.0,
+        h - 8.0,
+        t::RADIUS,
+        color::with_alpha(color::BORDER, sel),
+    );
+    let mut tx = x;
+    if let Some(dot) = dot {
+        ui.rounded(x, y + 17.0, 6.0, 6.0, 3.0, dot);
+        tx += 16.0;
+    }
+    let title = ui.fit(Face::Medium, BODY, title, w - 200.0);
+    ui.text(Face::Medium, BODY, tx, y + 10.0, color::TEXT, &title);
+    let meta = ui.fit(Face::Regular, SMALL, meta, w - 200.0);
+    ui.text(Face::Regular, SMALL, tx, y + 31.0, color::MUTED, &meta);
+    ui.text_right(Face::Regular, SMALL, x + w, y + 21.0, color::FAINT, right);
+    ui.divider(x, y + h, w);
+    h
+}
+/// An empty list: a serif line and a hint.
+fn empty(ui: &mut Ui, x: f32, y: f32, title: &str, hint: &str) {
+    ui.text_line(Face::Display, 22.0, 30.0, x, y + 32.0, color::TEXT, title);
+    ui.text(Face::Regular, BODY, x, y + 66.0, color::MUTED, hint);
+}
+
+fn worlds_page(
+    ui: &mut Ui,
+    x: f32,
+    w: f32,
+    worlds: &[crate::title::WorldEntry],
+    selected: Option<usize>,
+) {
+    let count = match worlds.len() {
+        0 => "No worlds yet. They live in the saves folder.".to_owned(),
+        1 => "1 world in the saves folder.".to_owned(),
+        n => format!("{n} worlds in the saves folder."),
+    };
+    let mut y = header(ui, x, "Singleplayer", &count);
+    actions_right(
+        ui,
+        x + w,
+        y - 24.0 - 58.0,
+        &[
+            (PLAY_WORLD, "Play", Kind::Primary, selected.is_some()),
+            (CREATE, "Create world", Kind::Secondary, true),
+        ],
+    );
+    ui.divider(x, y, w);
+    if worlds.is_empty() {
+        empty(ui, x, y, "A blank map.", "Create a world to begin.");
+        return;
+    }
+    let bottom = ui.h - 36.0;
+    for (i, world) in worlds.iter().enumerate() {
+        if y + 60.0 > bottom {
+            break;
+        }
+        let secs = world
+            .modified
+            .duration_since(std::time::UNIX_EPOCH)
+            .map_or(0, |d| d.as_secs());
+        let meta = format!("{}  ·  {}", crate::title::date_label(secs), world.folder);
+        let mode = if world.creative {
+            "Creative"
+        } else {
+            "Survival"
+        };
+        y += list_row(
+            ui,
+            WORLD + i as u64,
+            x,
+            y,
+            w,
+            selected == Some(i),
+            &world.name,
+            &meta,
+            mode,
+            None,
+        );
+    }
+}
+
+#[allow(clippy::too_many_arguments)]
+fn create_page(
+    ui: &mut Ui,
+    x: f32,
+    w: f32,
+    name: &str,
+    seed: &str,
+    creative: bool,
+    focus: u8,
+    caret: bool,
+) {
+    let mut y = header(
+        ui,
+        x,
+        "Create world",
+        "Generated by Horizon from the seed, as vanilla would.",
+    );
+    actions_right(
+        ui,
+        x + w,
+        y - 24.0 - 58.0,
+        &[
+            (MAKE, "Create", Kind::Primary, true),
+            (BACK, "Cancel", Kind::Ghost, true),
+        ],
+    );
+    ui.divider(x, y, w);
+    let fx = x + t::ROW_LABEL + 16.0;
+    let fw = (w - t::ROW_LABEL - 16.0).min(360.0);
+    for (i, label) in ["World name", "Seed", "Game mode"].iter().enumerate() {
+        let rh = 12.0 + CONTROL + 12.0;
+        ui.text_line(Face::Regular, BODY, rh, x, y, color::MUTED, label);
+        let r = [fx, y + 12.0, fw, CONTROL];
+        match i {
+            0 => ui.field(NAME, r, name, "New World", focus == 0, caret),
+            1 => ui.field(SEED, r, seed, "Random", focus == 1, caret),
+            _ => {
+                ui.segmented(
+                    MODE,
+                    fx,
+                    y + 12.0,
+                    &["Survival", "Creative"],
+                    usize::from(creative),
+                );
+            }
+        }
+        y += rh;
+        ui.divider(x, y, w);
+    }
+}
+
+fn multiplayer_page(ui: &mut Ui, x: f32, w: f32, screen: &Screen, caret: bool) {
+    match screen {
+        Screen::List {
+            servers,
+            selected,
+            pings,
+            lan,
+        } => {
+            let games = lan.games();
+            let sub = match servers.len() {
+                0 => "No saved servers. Worlds opened to LAN show up here too.".to_owned(),
+                1 => "1 saved server, and worlds opened to LAN.".to_owned(),
+                n => format!("{n} saved servers, and worlds opened to LAN."),
+            };
+            let mut y = header(ui, x, "Multiplayer", &sub);
+            let has = selected.is_some();
+            let saved = selected.is_some_and(|i| i < servers.len());
+            let mut items = vec![
+                (JOIN, "Join", Kind::Primary, has),
+                (ADD, "Add server", Kind::Secondary, true),
+                (DIRECT, "Direct connect", Kind::Secondary, true),
+                (REFRESH, "Refresh", Kind::Ghost, true),
+            ];
+            if saved {
+                items.push((EDIT, "Edit", Kind::Ghost, true));
+                items.push((DELETE, "Delete", Kind::Danger, true));
+            }
+            actions_right(ui, x + w, y - 24.0 - 58.0, &items);
+            ui.divider(x, y, w);
+            let pings = pings.lock().map(|p| p.clone()).unwrap_or_default();
+            let mut rows: Vec<(String, String, String, u32)> = servers
+                .iter()
+                .map(|s| {
+                    let (line, right, dot) = match pings.get(&s.ip) {
+                        Some(Ping::Ok {
+                            motd, players, ms, ..
+                        }) => (
+                            motd.lines().next().unwrap_or("").trim().to_owned(),
+                            format!("{players}  ·  {ms} ms"),
+                            color::ACCENT,
+                        ),
+                        Some(Ping::Failed(_)) => (
+                            "Can't reach the server".to_owned(),
+                            String::new(),
+                            color::DANGER,
+                        ),
+                        _ => ("Pinging…".to_owned(), String::new(), color::FAINT),
+                    };
+                    (s.name.clone(), format!("{line}  ·  {}", s.ip), right, dot)
+                })
+                .collect();
+            rows.extend(games.iter().map(|g| {
+                (
+                    "LAN world".to_owned(),
+                    format!("{}  ·  {}", g.motd, g.address),
+                    "On your network".to_owned(),
+                    color::ACCENT,
+                )
+            }));
+            if rows.is_empty() {
+                empty(
+                    ui,
+                    x,
+                    y,
+                    "Nobody here yet.",
+                    "Add a server, connect directly, or open a world to LAN.",
+                );
+                return;
+            }
+            let bottom = ui.h - 36.0;
+            for (i, (name, meta, right, dot)) in rows.iter().enumerate() {
+                if y + 60.0 > bottom {
+                    break;
+                }
+                y += list_row(
+                    ui,
+                    SERVER + i as u64,
+                    x,
+                    y,
+                    w,
+                    *selected == Some(i),
+                    name,
+                    meta,
+                    right,
+                    Some(*dot),
+                );
+            }
+        }
+        Screen::Edit {
+            index,
+            name,
+            address,
+            focus,
+        } => {
+            let title = if index.is_some() {
+                "Edit server"
+            } else {
+                "Add server"
+            };
+            let mut y = header(
+                ui,
+                x,
+                title,
+                "Saved to servers.dat, like vanilla's server list.",
+            );
+            let ok = horizon_protocol::servers::parse_address(address).is_some();
+            actions_right(
+                ui,
+                x + w,
+                y - 24.0 - 58.0,
+                &[
+                    (DONE, "Save", Kind::Primary, ok),
+                    (BACK, "Cancel", Kind::Ghost, true),
+                ],
+            );
+            ui.divider(x, y, w);
+            let fx = x + t::ROW_LABEL + 16.0;
+            let fw = (w - t::ROW_LABEL - 16.0).min(360.0);
+            for (i, (label, value, hint)) in [
+                ("Name", name, "Minecraft Server"),
+                ("Address", address, "play.example.net"),
+            ]
+            .iter()
+            .enumerate()
+            {
+                let rh = 12.0 + CONTROL + 12.0;
+                ui.text_line(Face::Regular, BODY, rh, x, y, color::MUTED, label);
+                let fid = if i == 0 { FIELD_A } else { FIELD_B };
+                ui.field(
+                    fid,
+                    [fx, y + 12.0, fw, CONTROL],
+                    value,
+                    hint,
+                    usize::from(*focus) == i,
+                    caret,
+                );
+                y += rh;
+                ui.divider(x, y, w);
+            }
+        }
+        Screen::Direct { address } => {
+            let y = header(
+                ui,
+                x,
+                "Direct connect",
+                "Join a server once without saving it.",
+            );
+            let ok = horizon_protocol::servers::parse_address(address).is_some();
+            actions_right(
+                ui,
+                x + w,
+                y - 24.0 - 58.0,
+                &[
+                    (DONE, "Join", Kind::Primary, ok),
+                    (BACK, "Cancel", Kind::Ghost, true),
+                ],
+            );
+            ui.divider(x, y, w);
+            let rh = 12.0 + CONTROL + 12.0;
+            ui.text_line(Face::Regular, BODY, rh, x, y, color::MUTED, "Address");
+            let fx = x + t::ROW_LABEL + 16.0;
+            ui.field(
+                FIELD_A,
+                [fx, y + 12.0, (w - t::ROW_LABEL - 16.0).min(360.0), CONTROL],
+                address,
+                "host:port",
+                true,
+                caret,
+            );
+            ui.divider(x, y + rh, w);
+        }
+        Screen::Disconnected { reason } => {
+            let mut y = header(
+                ui,
+                x,
+                "Connection lost",
+                "The server closed the connection.",
+            );
+            ui.divider(x, y, w);
+            y += 16.0;
+            // The launcher's error note: a danger dot beside the message.
+            let lines = wrap(ui, reason, w - 40.0);
+            let box_h = 24.0 + lines.len() as f32 * 19.0;
+            ui.rounded(x, y, w, box_h, t::RADIUS, color::RAISED);
+            ui.border(x, y, w, box_h, t::RADIUS, color::BORDER);
+            ui.rounded(x + 12.0, y + 18.0, 6.0, 6.0, 3.0, color::DANGER);
+            for (i, line) in lines.iter().enumerate() {
+                ui.text_line(
+                    Face::Regular,
+                    BODY,
+                    19.0,
+                    x + 28.0,
+                    y + 12.0 + i as f32 * 19.0,
+                    color::TEXT,
+                    line,
+                );
+            }
+            y += box_h + 16.0;
+            let bw = ui.button_width("Back to servers", false);
+            ui.button(
+                BACK,
+                [x, y, bw, CONTROL],
+                "Back to servers",
+                Kind::Secondary,
+                true,
+            );
+        }
+    }
+}
+/// Greedy word wrap in dp.
+pub fn wrap(ui: &Ui, text: &str, width: f32) -> Vec<String> {
+    let mut lines = Vec::new();
+    for para in text.lines() {
+        let mut line = String::new();
+        for word in para.split_whitespace() {
+            let next = if line.is_empty() {
+                word.to_owned()
+            } else {
+                format!("{line} {word}")
+            };
+            if !line.is_empty() && ui.measure(Face::Regular, BODY, &next) > width {
+                lines.push(std::mem::replace(&mut line, word.to_owned()));
+            } else {
+                line = next;
+            }
+        }
+        lines.push(line);
+    }
+    lines
+}
+
+/// The pause menu in Horizon's style: the launcher's sidebar over the
+/// blurred world, with the game's actions as a page. Ids match
+/// `game/screens.rs`'s PauseScreen actions: 0 back to game, 1 options,
+/// 2 save and quit, 3 statistics, 4 advancements, 9 world options.
+pub mod pause {
+    use super::*;
+    fn act(a: u8) -> u64 {
+        id("pause", u64::from(a))
+    }
+    pub fn draw(ui: &mut Ui, world: &str, quit_label: &str, opened: Instant) {
+        let (w, h) = (ui.w, ui.h);
+        let p = t::ease_out_quint(opened.elapsed().as_secs_f32() / t::move_());
+        ui.opacity = p;
+        ui.atmosphere(0.35, 1.0);
+        ui.offset = (-16.0 * (1.0 - p), 0.0);
+        ui.fill(0.0, 0.0, SIDEBAR, h, color::with_alpha(color::SIDEBAR, 0.8));
+        ui.vline(SIDEBAR - 1.0, 0.0, h, color::BORDER);
+        ui.text_line(
+            Face::Display,
+            22.0,
+            30.0,
+            22.0,
+            16.0,
+            color::TEXT,
+            "Horizon",
+        );
+        ui.sidebar_list(
+            id("pause.nav", 0),
+            12.0,
+            66.0,
+            SIDEBAR - 24.0,
+            &["Game", "Advancements", "Statistics", "Options"],
+            0,
+        );
+        ui.text(
+            Face::Regular,
+            SMALL,
+            22.0,
+            h - 12.0 - 18.0,
+            color::FAINT,
+            "Horizon 26.3",
+        );
+        ui.offset = (0.0, 8.0 * (1.0 - p));
+        let x = SIDEBAR + 48.0;
+        let cw = (w - x - 48.0).min(760.0);
+        let mut y = 36.0;
+        ui.text(Face::Medium, SMALL, x, y, color::FAINT, "Game paused");
+        y += 22.0;
+        let title = ui.fit(Face::Display, t::HERO, world, cw);
+        ui.text_line(Face::Display, t::HERO, 58.0, x, y, color::TEXT, &title);
+        y += 58.0 + 24.0;
+        let bw = ui.button_width("Back to game", true).max(120.0);
+        ui.button(
+            act(0),
+            [x, y, bw, CONTROL_LARGE],
+            "Back to game",
+            Kind::Primary,
+            true,
+        );
+        let lw = ui.button_width("Open to LAN", true);
+        ui.button(
+            act(9),
+            [x + bw + 8.0, y, lw, CONTROL_LARGE],
+            "Open to LAN",
+            Kind::Secondary,
+            true,
+        );
+        y += CONTROL_LARGE + 24.0;
+        ui.divider(x, y, cw);
+        let rh = ui.row(
+            x,
+            y,
+            "Leave",
+            "Saves the world, then returns to the title.",
+            cw - t::ROW_LABEL - 220.0,
+        );
+        let qw = ui.button_width(quit_label, false);
+        ui.button(
+            act(2),
+            [x + cw - qw, y + (rh - CONTROL) / 2.0, qw, CONTROL],
+            quit_label,
+            Kind::Danger,
+            true,
+        );
+        y += rh;
+        ui.divider(x, y, cw);
+        ui.opacity = 1.0;
+        ui.offset = (0.0, 0.0);
+    }
+    /// The PauseScreen action under a click, if any.
+    pub fn click(
+        atlas: &HudAtlas,
+        batch: &mut HudBatch,
+        x: f32,
+        y: f32,
+        world: &str,
+        quit_label: &str,
+    ) -> Option<u8> {
+        let mut ui = Ui::dry(atlas, batch, (x, y));
+        draw(
+            &mut ui,
+            world,
+            quit_label,
+            Instant::now() - std::time::Duration::from_secs(5),
+        );
+        let hit = ui.hit((x, y))?;
+        let nav = id("pause.nav", 0);
+        match hit {
+            h if h == nav => Some(0),
+            h if h == nav + 1 => Some(4),
+            h if h == nav + 2 => Some(3),
+            h if h == nav + 3 => Some(1),
+            h => [0u8, 1, 2, 3, 4, 9].into_iter().find(|&a| act(a) == h),
+        }
+    }
+}

crates/horizon-client/src/game.rs

@@ -4,6 +4,7 @@ mod advancements;
 mod advancements_screen;
 mod allays;
 mod armor_stands;
+mod backdrop;
 mod banners;
 mod beacon;
 mod block_entity_anims;
@@ -694,6 +695,10 @@ struct Game<'a> {
     settings: Settings,
     /// Where the options screen returns: true = title, false = pause menu.
     options_from_title: bool,
+    /// The live title backdrop (game/backdrop.rs).
+    backdrop: backdrop::Backdrop,
+    /// When the pause menu opened (Horizon style's entrance).
+    pause_since: Option<Instant>,
     dragging: bool,
     /// `ClientAvatarState`: walked distance and view bob.
     avatar: horizon_client::camera::AvatarBob,
@@ -2969,7 +2974,15 @@ impl Game<'_> {
             return batch;
         }
         if let Some(title) = &self.title {
-            title.draw(&self.res.atlas, &mut batch, self.cursor);
+            if horizon_client::ui_theme::horizon() {
+                let fade = self.backdrop_fade();
+                let mut ui =
+                    horizon_client::ui_theme::Ui::new(&self.res.atlas, &mut batch, self.cursor);
+                title.draw_horizon(&mut ui, fade);
+                ui.finish();
+            } else {
+                title.draw(&self.res.atlas, &mut batch, self.cursor);
+            }
             return batch;
         }
         let atlas_ptr: *const HudAtlas = &self.res.atlas;
@@ -2994,7 +3007,8 @@ impl Game<'_> {
         // the sleep overlay, debug screen and open screens still draw.
         let spectator = self.spectator();
         let (wi, hi) = (w as i32, h as i32);
-        if !self.ui.hide_gui {
+        // Horizon's pause menu sits over the blurred world alone.
+        if !self.ui.hide_gui && !self.horizon_pause() {
             self.draw_spyglass(&mut batch);
             // Hud.extractCrosshair / extractItemHotbar / extractPlayerHealth /
             // extractVehicleHealth and the experience bar, laid out by hud_layout.
@@ -7150,7 +7164,13 @@ impl Game<'_> {
             return Ok(false);
         };
         let alpha = self.clock.fraction();
-        let (camera, underwater, view_yaw, view_pitch) = match self.camera_view(alpha as f32) {
+        let live = self.backdrop_live();
+        let view = if live {
+            self.backdrop_view()
+        } else {
+            self.camera_view(alpha as f32)
+        };
+        let (camera, underwater, view_yaw, view_pitch) = match view {
             Some((c, yaw, pitch)) => {
                 let s =
                     self.world
@@ -7236,7 +7256,7 @@ impl Game<'_> {
                 entities.extend(dragon);
             }
         }
-        let celestial = if title {
+        let celestial = if title && !live {
             self.panorama_geometry()
         } else if self.dim == Dim::Overworld
             && self.potions.effects.get("darkness").is_none()
@@ -7262,12 +7282,14 @@ impl Game<'_> {
         if !title {
             self.end_geometry(camera, &mut entities);
         }
-        if !title && self.dim == Dim::Overworld {
+        if (!title || live) && self.dim == Dim::Overworld {
             self.cloud_geometry(&sky, camera, alpha, &mut entities);
             self.weather_geometry(camera, alpha, &mut entities);
         }
         // PanoramaRenderer: the title cube spins at 0.1 degrees per tick, pitched 10 degrees.
-        let (yaw, pitch) = if title {
+        let (yaw, pitch) = if live {
+            (view_yaw, view_pitch)
+        } else if title {
             (-(self.started.elapsed().as_secs_f32() * 2.0) % 360.0, 10.0)
         } else {
             (view_yaw, view_pitch)
@@ -7287,7 +7309,9 @@ impl Game<'_> {
             camera,
             yaw,
             pitch,
-            fov_degrees: if title {
+            fov_degrees: if live {
+                72.0
+            } else if title {
                 85.0
             } else {
                 self.fov_degrees(alpha as f32, camera.to_array())
@@ -7300,7 +7324,7 @@ impl Game<'_> {
             sky,
             distance: (self.streaming.radius * 16) as f32,
             underwater,
-            title,
+            title: title && !live,
             skybox: self.dim == Dim::Overworld,
             end_sky: self.dim == Dim::End,
             environment_fog: (self.dim == Dim::Nether).then_some((sky.fog_start, sky.fog_end)),
@@ -7334,6 +7358,13 @@ impl Game<'_> {
             darkness: self.darkness_lighting(alpha as f32),
             night_vision: self.night_vision_intensity(),
             block_flicker: self.res.fog.state.block_light_flicker,
+            post: if live {
+                Some(horizon_client::post::PostGrade::FROST)
+            } else if self.horizon_pause() {
+                Some(horizon_client::post::PostGrade::PAUSE)
+            } else {
+                None
+            },
         };
         self.renderer.as_mut().ok_or("renderer")?.render(&frame)
     }
@@ -7627,6 +7658,15 @@ impl ApplicationHandler for Game<'_> {
         ) {
             self.last_input = Instant::now();
         }
+        if let WindowEvent::MouseInput {
+            state,
+            button: MouseButton::Left,
+            ..
+        } = &event
+        {
+            // The press state of Horizon-style buttons.
+            horizon_client::ui_theme::set_pressed(*state == ElementState::Pressed);
+        }
         let result: Result<()> = (|| {
             match event {
                 WindowEvent::CloseRequested => {
@@ -7752,9 +7792,14 @@ impl ApplicationHandler for Game<'_> {
                         .as_ref()
                         .map(|r| [r.config.width, r.config.height])
                         .unwrap_or([1, 1]);
-                    let b = HudBatch::new(size);
+                    let mut b = HudBatch::new(size);
+                    let atlas = &self.res.atlas;
                     let action = self.title.as_mut().map_or(Action::None, |t| {
-                        t.click(self.cursor.0, self.cursor.1, (b.width, b.height))
+                        if horizon_client::ui_theme::horizon() {
+                            t.click_horizon(atlas, &mut b, self.cursor.0, self.cursor.1)
+                        } else {
+                            t.click(self.cursor.0, self.cursor.1, (b.width, b.height))
+                        }
                     });
                     match action {
                         Action::Quit => event_loop.exit(),
@@ -7920,6 +7965,7 @@ impl ApplicationHandler for Game<'_> {
                 WindowEvent::KeyboardInput { event, .. } if self.title.is_some() => {
                     if event.state == ElementState::Pressed
                         && let Some(title) = self.title.as_mut()
+                        && !title.skip_opening()
                     {
                         match event.physical_key {
                             PhysicalKey::Code(KeyCode::Backspace) => title.backspace(),
@@ -8001,6 +8047,11 @@ impl ApplicationHandler for Game<'_> {
                     self.pitch = (self.pitch
                         + (turn(KeyCode::ArrowDown) - turn(KeyCode::ArrowUp)) * 90.0 * secs)
                         .clamp(-90.0, 90.0);
+                    self.update_backdrop()?;
+                    horizon_client::ui_theme::set_backdrop(self.backdrop_fade());
+                    if self.screen != Screen::Paused {
+                        self.pause_since = None;
+                    }
                     if self.title.is_none() {
                         self.update_world();
                         self.spawn_player()?;
@@ -8013,6 +8064,8 @@ impl ApplicationHandler for Game<'_> {
                             self.tick()?;
                             self.tick_ambience();
                             self.tick_fov();
+                        } else if self.title.is_some() {
+                            self.tick_backdrop();
                         }
                         self.tick_music();
                         self.tick_sound_engine();
@@ -8246,6 +8299,14 @@ pub fn run() -> Result<()> {
     let now = Instant::now();
     let game_root = options.resources.clone();
     let mut settings = Settings::load(&std::env::current_dir()?.join("options.txt"));
+    horizon_client::ui_theme::load_preferences(&std::env::current_dir()?);
+    // Scripted and frame-limited runs (the parity harnesses) see vanilla's
+    // screens unless HORIZON_MENU_STYLE asks otherwise.
+    if (options.frames.is_some() || options.control.is_some())
+        && std::env::var_os("HORIZON_MENU_STYLE").is_none()
+    {
+        horizon_client::ui_theme::set_style(horizon_client::ui_theme::MenuStyle::Classic);
+    }
     if let Some(d) = options.distance_override {
         settings.render_distance = d;
     }
@@ -8363,6 +8424,8 @@ pub fn run() -> Result<()> {
         hand_item: None,
         settings,
         options_from_title: false,
+        backdrop: Default::default(),
+        pause_since: None,
         dragging: false,
         avatar: Default::default(),
         flash: 0,
@@ -8493,7 +8556,16 @@ pub fn run() -> Result<()> {
             let (seed, creative) = (game.options.seed, game.options.creative);
             game.open_world(&folder, None, Some(seed), creative)?;
         }
-        None => game.title = Some(Title::new(std::env::current_dir()?.join("saves"))),
+        None => {
+            let title = Title::new(std::env::current_dir()?.join("saves"));
+            // The launcher's opening, once per session and only in Horizon's style.
+            if horizon_client::ui_theme::horizon() && game.options.frames.is_none() {
+                title
+                    .opening
+                    .set(Some(horizon_client::front::Opening::new()));
+            }
+            game.title = Some(title);
+        }
     }
     if let (Some(script), Some(output)) = (
         std::env::var_os("HORIZON_COMMAND_SCRIPT"),

crates/horizon-client/src/game/backdrop.rs

@@ -0,0 +1,245 @@
+//! The live title backdrop (Menu style: Horizon): a frozen landscape that
+//! Horizon generates and renders itself behind the title screens, seen
+//! through a slow orbiting camera, falling snow, an overcast sky and the cold
+//! blur and grade of `gfx::PostGrade`. Nothing is bundled: the chunks come
+//! from the vanilla generator for a fixed seed and are cached in
+//! `saves/.horizon-title/backdrop` (no level.dat, so no world list entry).
+//! The ice-spikes spot is found once with `/locate biome`'s search and kept
+//! in `spot.txt` there.
+use super::Game;
+use horizon_client::{
+    Result,
+    save::{Persistent, SaveDir},
+    streaming::Streaming,
+    vanillagen::VanillaTerrain,
+    world::{Weather, World},
+};
+use horizon_core::biome::{BiomeZoom, obfuscate_seed};
+use std::{
+    sync::{Arc, Mutex},
+    time::Instant,
+};
+
+/// The world the backdrop is cut from (HORIZON_BACKDROP_SEED overrides it).
+const SEED: i64 = 2_026_031_337;
+/// The biome the camera looks for.
+const BIOME: &str = "minecraft:ice_spikes";
+/// Late morning: the snow reads clearly; the grade (`PostGrade::FROST`) makes it cold.
+const DAY_TIME: i64 = 4_000;
+
+#[derive(Default)]
+pub(super) struct Backdrop {
+    pub active: bool,
+    /// The search for the spot, then the spot (block x, z).
+    spot: Arc<Mutex<Option<Option<(i32, i32)>>>>,
+    centred: bool,
+    /// Camera position once the ground under it has loaded.
+    pub camera: Option<glam::DVec3>,
+    pub ready: Option<Instant>,
+    pub started: Option<Instant>,
+}
+fn seed() -> i64 {
+    std::env::var("HORIZON_BACKDROP_SEED")
+        .ok()
+        .and_then(|s| s.parse().ok())
+        .unwrap_or(SEED)
+}
+impl Game<'_> {
+    /// How visible the live backdrop is (0 until its first chunks are drawn).
+    pub(super) fn backdrop_fade(&self) -> f32 {
+        let Some(at) = self.backdrop.ready else {
+            return 0.0;
+        };
+        let x = (at.elapsed().as_secs_f32() / 1.6).clamp(0.0, 1.0);
+        x * x * (3.0 - 2.0 * x)
+    }
+    /// Whether the frame should draw the backdrop world instead of the panorama.
+    pub(super) fn backdrop_live(&self) -> bool {
+        self.title.is_some() && self.backdrop.active && self.backdrop.camera.is_some()
+    }
+    /// The orbiting camera: position, yaw and pitch.
+    pub(super) fn backdrop_view(&self) -> Option<(glam::DVec3, f32, f32)> {
+        let c = self.backdrop.camera?;
+        let t = self
+            .backdrop
+            .started
+            .map_or(0.0, |s| s.elapsed().as_secs_f32());
+        // A full turn in about six minutes.
+        let yaw = (200.0 + t * 1.0) % 360.0;
+        let pitch = 6.0 + (t * 0.05).sin() * 2.0;
+        Some((c, yaw, pitch))
+    }
+    /// Called every frame while the title is up.
+    pub(super) fn update_backdrop(&mut self) -> Result<()> {
+        let wanted = self.title.is_some()
+            && horizon_client::ui_theme::horizon()
+            && self.renderer.is_some()
+            && self.options.frames.is_none();
+        if !wanted {
+            if self.backdrop.active && self.title.is_some() {
+                self.stop_backdrop();
+            }
+            if self.title.is_none() && self.backdrop.active {
+                // open_world / connect_server replaced the world and streaming.
+                self.backdrop = Backdrop::default();
+            }
+            return Ok(());
+        }
+        if !self.backdrop.active {
+            self.start_backdrop()?;
+        }
+        let found = *self.backdrop.spot.lock().unwrap_or_else(|e| e.into_inner());
+        let Some(Some((x, z))) = found else {
+            return Ok(());
+        };
+        if !self.backdrop.centred {
+            self.backdrop.centred = true;
+            self.streaming.center = (x >> 4, z >> 4);
+            self.streaming.paused = false;
+        }
+        self.update_world();
+        if self.backdrop.camera.is_none()
+            && (-2..=2)
+                .all(|dz| (-2..=2).all(|dx| self.streaming.is_lit((x >> 4) + dx, (z >> 4) + dz)))
+        {
+            // Above the tallest block nearby, so no spike pokes through the lens.
+            let mut top = 64;
+            for dz in (-12..=12).step_by(3) {
+                for dx in (-12..=12).step_by(3) {
+                    if let Some(y) = self.surface_y(x + dx, z + dz) {
+                        top = top.max(y);
+                    }
+                }
+            }
+            let ground = self.surface_y(x, z).unwrap_or(top);
+            let y = (ground + 22).max(top + 4);
+            self.backdrop.camera = Some(glam::DVec3::new(
+                f64::from(x) + 0.5,
+                f64::from(y),
+                f64::from(z) + 0.5,
+            ));
+        }
+        if self.backdrop.camera.is_some()
+            && self.backdrop.ready.is_none()
+            && self
+                .renderer
+                .as_ref()
+                .is_some_and(|r| r.section_count() > 40)
+        {
+            self.backdrop.ready = Some(Instant::now());
+        }
+        Ok(())
+    }
+    /// The world tick of the backdrop: time passes for clouds and snow only.
+    pub(super) fn tick_backdrop(&mut self) {
+        if self.backdrop.active {
+            self.world.game_time += 1;
+            // The snow's fall follows the client tick counter.
+            self.ticks += 1;
+        }
+    }
+    fn surface_y(&self, x: i32, z: i32) -> Option<i32> {
+        let air = self.res.facts.air;
+        (-60..320).rev().find(|&y| self.world.block(x, y, z) != air)
+    }
+    fn start_backdrop(&mut self) -> Result<()> {
+        let seed = seed();
+        let root = std::env::current_dir()?
+            .join("saves")
+            .join(".horizon-title")
+            .join("backdrop");
+        std::fs::create_dir_all(&root)?;
+        let save = Arc::new(SaveDir::new(root.join(format!("{seed}"))));
+        let res = &*self.res;
+        let inner = Arc::new(
+            VanillaTerrain::new(
+                &self.options.resources.join("worldgen"),
+                res.assets.registry,
+                &res.biomes,
+                seed,
+            )
+            .map_err(|e| format!("title backdrop: {e}"))?,
+        );
+        let mut streaming = Streaming::new(
+            Arc::new(Persistent {
+                inner: inner.clone(),
+                save: save.clone(),
+                registry: res.assets.clone(),
+                biomes: res.biomes.clone(),
+            }),
+            res.context.clone(),
+            res.threads.min(6),
+        );
+        streaming.radius = self.settings.render_distance.clamp(4, 10);
+        streaming.biome_blend = self.settings.biome_blend;
+        streaming.smooth_lighting = self.settings.smooth_lighting;
+        streaming.cutout_leaves = self.settings.cutout_leaves;
+        streaming.biome_zoom = BiomeZoom::new(obfuscate_seed(seed));
+        streaming.paused = true;
+        self.streaming = streaming;
+        self.save = save;
+        let mut world = World::new(self.res.facts.air, seed);
+        world.day_time = DAY_TIME;
+        world.game_time = 6000;
+        // Light snow: the weather renders as snow in frozen biomes.
+        world.weather = Weather {
+            clear_time: 0,
+            rain_time: i32::MAX / 2,
+            thunder_time: i32::MAX / 2,
+            raining: true,
+            thundering: false,
+            rain_level: (0.35, 0.35),
+            thunder_level: (0.0, 0.0),
+        };
+        self.world = world;
+        self.dim = super::Dim::Overworld;
+        if let Some(r) = self.renderer.as_mut() {
+            r.clear_sections();
+        }
+        self.backdrop = Backdrop {
+            active: true,
+            started: Some(Instant::now()),
+            ..Default::default()
+        };
+        // Find (or recall) the spot off the main thread.
+        let spot = self.backdrop.spot.clone();
+        std::fs::create_dir_all(root.join(format!("{seed}")))?;
+        let cache = root.join(format!("{seed}")).join("spot.txt");
+        std::thread::Builder::new()
+            .name("horizon-backdrop".into())
+            .spawn(move || {
+                let known = std::fs::read_to_string(&cache).ok().and_then(|t| {
+                    let mut it = t.split_whitespace().map(|v| v.parse::<i32>().ok());
+                    Some((it.next()??, it.next()??))
+                });
+                let found = known.or_else(|| {
+                    let allowed = |name: &str| name == BIOME;
+                    let search = horizon_world::worldgen::generator::BiomeSearch {
+                        allowed: &allowed,
+                        origin: [0, 64, 0],
+                        radius: 6400,
+                        horizontal: 32,
+                        vertical: 64,
+                        min_y: -64,
+                        max_y: 320,
+                    };
+                    let found = inner.find_closest_biome(&search);
+                    eprintln!("Horizon: title backdrop: {BIOME} at {found:?}");
+                    let (_, p) = found?;
+                    let _ = std::fs::write(&cache, format!("{} {}\n", p[0], p[2]));
+                    Some((p[0], p[2]))
+                });
+                *spot.lock().unwrap_or_else(|e| e.into_inner()) =
+                    Some(Some(found.unwrap_or((0, 0))));
+            })?;
+        Ok(())
+    }
+    fn stop_backdrop(&mut self) {
+        self.streaming.paused = true;
+        self.world = World::new(self.res.facts.air, 0);
+        if let Some(r) = self.renderer.as_mut() {
+            r.clear_sections();
+        }
+        self.backdrop = Backdrop::default();
+    }
+}

crates/horizon-client/src/game/screens.rs

@@ -52,7 +52,32 @@ fn death_buttons(w: f32, h: f32) -> [(f32, f32, &'static str, u8); 2] {
     ]
 }
 impl Game<'_> {
+    /// Whether the pause menu is drawn in Horizon's style (over a blurred world).
+    pub(super) fn horizon_pause(&self) -> bool {
+        self.screen == Screen::Paused && self.title.is_none() && horizon_client::ui_theme::horizon()
+    }
+    fn pause_labels(&self) -> (String, &'static str) {
+        let world = if self.remote.is_some() {
+            "Multiplayer".to_owned()
+        } else {
+            self.level.name.clone()
+        };
+        let quit = if self.remote.is_some() {
+            "Disconnect"
+        } else {
+            "Save and quit"
+        };
+        (world, quit)
+    }
     pub(super) fn draw_pause_menu(&mut self, batch: &mut HudBatch) {
+        if horizon_client::ui_theme::horizon() {
+            let opened = *self.pause_since.get_or_insert_with(std::time::Instant::now);
+            let (world, quit) = self.pause_labels();
+            let mut ui = horizon_client::ui_theme::Ui::new(&self.res.atlas, batch, self.cursor);
+            horizon_client::front::pause::draw(&mut ui, &world, quit, opened);
+            ui.finish();
+            return;
+        }
         let atlas = &self.res.atlas;
         let (w, h) = (batch.width, batch.height);
         ui::menu_background(batch, atlas, 0.0, 0.0, w, h, true);
@@ -102,10 +127,27 @@ impl Game<'_> {
             let b = HudBatch::new(size);
             (b.width, b.height)
         };
-        let hit = pause_buttons(w, h)
-            .into_iter()
-            .find(|b| b.5 && ui::hovered(self.cursor, b.0, b.1, b.2, 20.0))
-            .map(|b| b.4);
+        let hit = if horizon_client::ui_theme::horizon() {
+            let size = self
+                .renderer
+                .as_ref()
+                .map_or([1, 1], |r| [r.config.width, r.config.height]);
+            let mut b = HudBatch::new(size);
+            let (world, quit) = self.pause_labels();
+            horizon_client::front::pause::click(
+                &self.res.atlas,
+                &mut b,
+                self.cursor.0,
+                self.cursor.1,
+                &world,
+                quit,
+            )
+        } else {
+            pause_buttons(w, h)
+                .into_iter()
+                .find(|b| b.5 && ui::hovered(self.cursor, b.0, b.1, b.2, 20.0))
+                .map(|b| b.4)
+        };
         match hit {
             Some(0) => {
                 self.screen = Screen::Playing;

crates/horizon-client/src/gfx.rs

@@ -96,6 +96,8 @@ pub struct Frame<'a> {
     pub night_vision: f32,
     /// Torch flicker added to the block light factor of 1.4.
     pub block_flicker: f32,
+    /// Blur and grade the frame under a Horizon-style menu (`post`).
+    pub post: Option<crate::post::PostGrade>,
 }
 /// One frame of the world border wall (`WorldBorderRenderer.render`).
 #[derive(Clone, Debug)]
@@ -162,6 +164,8 @@ pub struct Renderer {
     reachable_from: Option<SectionKey>,
     visibility_dirty: bool,
     pub hud: HudRenderer,
+    /// The menus' backdrop blur, made on first use.
+    post: Option<crate::post::Post>,
     pub info: wgpu::AdapterInfo,
     pub suspended: bool,
     pub drawn_sections: usize,
@@ -1086,6 +1090,7 @@ impl Renderer {
             reachable_from: None,
             visibility_dirty: true,
             hud,
+            post: None,
             info,
             suspended: size.width == 0 || size.height == 0,
             drawn_sections: 0,
@@ -1853,6 +1858,23 @@ impl Renderer {
                 pass.draw_indexed(0..6, (i * 4) as i32, 0..1);
             }
         }
+        if let Some(grade) = &frame.post
+            && self.config.usage.contains(wgpu::TextureUsages::COPY_SRC)
+        {
+            let format = self.config.format;
+            let device = &self.device;
+            self.post
+                .get_or_insert_with(|| crate::post::Post::new(device, format))
+                .apply(
+                    &self.device,
+                    &self.queue,
+                    &mut encoder,
+                    &surface_frame.texture,
+                    &view_target,
+                    [self.config.width, self.config.height],
+                    grade,
+                );
+        }
         self.hud.draw(
             &self.device,
             &self.queue,

crates/horizon-client/src/hud.rs

@@ -204,6 +204,13 @@ impl HudAtlas {
         for i in 0..SKIN_SLOTS {
             images.push((format!("horizon/skin{i}"), 64, 64, vec![0; 64 * 64 * 4]));
         }
+        // Horizon-style menu text and corner masks (ui_theme), rasterized at run time.
+        images.push((
+            "horizon/ui-text".into(),
+            2048,
+            1024,
+            vec![0; 2048 * 1024 * 4],
+        ));
         images.sort_by(|a, b| b.2.cmp(&a.2).then(b.1.cmp(&a.1)));
         let width = 4096u32;
         let mut placements = Vec::with_capacity(images.len());

crates/horizon-client/src/lib.rs

@@ -44,6 +44,7 @@ pub mod fastutil_order;
 pub mod flatgen;
 pub mod fog;
 pub mod font;
+pub mod front;
 pub mod gamerules;
 pub mod gfx;
 pub mod gossip;
@@ -79,12 +80,14 @@ pub mod nbt_path;
 pub mod net;
 pub mod options_file;
 pub mod options_fixes;
+pub mod options_horizon;
 pub mod options_ui;
 pub mod pack_screen;
 pub mod packs;
 pub mod particles;
 pub mod patrol;
 pub mod pose;
+pub mod post;
 pub mod projectiles;
 pub mod raid;
 pub mod random_sequences;
@@ -116,6 +119,7 @@ pub mod testgen;
 pub mod text;
 pub mod title;
 pub mod ui;
+pub mod ui_theme;
 pub mod vanillagen;
 pub mod window;
 pub mod world;

crates/horizon-client/src/multiplayer.rs

@@ -108,6 +108,13 @@ fn entry_address(servers: &[ServerEntry], lan: &Scanner, index: usize) -> Option
 }
 
 impl Screen {
+    /// The address of list row `row` (saved servers, then LAN games).
+    pub fn address_of(&self, row: usize) -> Option<String> {
+        match self {
+            Self::List { servers, lan, .. } => entry_address(servers, lan, row),
+            _ => None,
+        }
+    }
     pub fn list(saves: &Path) -> Self {
         let servers = servers::load(&servers_file(saves));
         let pings: Pings = Arc::default();

crates/horizon-client/src/options_horizon.rs

@@ -0,0 +1,518 @@
+//! The options screen in Horizon's menu style, laid out like the launcher's
+//! Settings page: a sidebar with the sliding selection (one item per
+//! section), then the section's page header and settings rows (label column,
+//! value, control on the right) between 1px dividers.
+//!
+//! Adding settings (for example the Simple/Advanced graphics menu): add rows
+//! to a section in [`SECTIONS`], or a new section. A row is an [`HRow`]: an
+//! existing option (`Opt`, drawn as a switch, a slider or a value button from
+//! its kind), a header, or a button opening one of vanilla's pages. New kinds
+//! of control belong in `ui_theme` so the launcher-matching look stays in one
+//! place. Everything else (sliders dragging, scrolling, Done) is handled here.
+use crate::{
+    hud::{HudAtlas, HudBatch},
+    options_ui::{Event, Kind, Opt, OptionsUi, Page, apply_preset},
+    settings::{SOUND_SOURCES, Settings},
+    ui_theme::{
+        self as t, CONTROL, Face, Kind as Button, MenuStyle, ROW_LABEL, SIDEBAR, SMALL, Ui, color,
+        id,
+    },
+};
+
+/// One row of a section.
+#[derive(Clone, Copy, Debug)]
+pub enum HRow {
+    Header(&'static str),
+    Opt(Opt),
+    /// A label, a value and a button opening one of vanilla's pages.
+    Page(&'static str, &'static str, Page),
+    /// Menu style: Horizon / Classic.
+    Style,
+}
+/// A sidebar section: name, description, rows.
+pub struct Section {
+    pub name: &'static str,
+    pub blurb: &'static str,
+    pub rows: fn(&Settings) -> Vec<HRow>,
+}
+pub const SECTIONS: &[Section] = &[
+    Section {
+        name: "Video",
+        blurb: "Display, quality and how the world is drawn.",
+        rows: |_| {
+            let mut r = vec![HRow::Header("Display")];
+            r.extend(
+                [
+                    Opt::Fullscreen,
+                    Opt::Vsync,
+                    Opt::MaxFps,
+                    Opt::InactivityFps,
+                    Opt::GuiScale,
+                    Opt::Gamma,
+                ]
+                .map(HRow::Opt),
+            );
+            r.push(HRow::Header("Quality"));
+            r.extend(
+                [
+                    Opt::Preset,
+                    Opt::RenderDistance,
+                    Opt::SimulationDistance,
+                    Opt::SmoothLighting,
+                    Opt::Clouds,
+                    Opt::CloudRange,
+                    Opt::Particles,
+                    Opt::Mipmaps,
+                    Opt::EntityShadows,
+                    Opt::EntityDistance,
+                    Opt::BiomeBlend,
+                    Opt::CutoutLeaves,
+                    Opt::ImprovedTransparency,
+                    Opt::WeatherRadius,
+                    Opt::ChunkBuilder,
+                ]
+                .map(HRow::Opt),
+            );
+            r.push(HRow::Header("Preferences"));
+            r.extend(
+                [
+                    Opt::Fov,
+                    Opt::ViewBobbing,
+                    Opt::Autosave,
+                    Opt::Vignette,
+                    Opt::AttackIndicator,
+                    Opt::ChunkFade,
+                ]
+                .map(HRow::Opt),
+            );
+            r
+        },
+    },
+    Section {
+        name: "Audio",
+        blurb: "Volume for every kind of sound, and subtitles.",
+        rows: |_| {
+            let mut r: Vec<HRow> = (0..SOUND_SOURCES.len())
+                .map(|i| HRow::Opt(Opt::Volume(i)))
+                .collect();
+            r.push(HRow::Opt(Opt::ShowSubtitles));
+            r
+        },
+    },
+    Section {
+        name: "Controls",
+        blurb: "Keys, the mouse and how movement keys behave.",
+        rows: |_| {
+            let mut r = vec![HRow::Page(
+                "Key binds",
+                "Every action and its key",
+                Page::KeyBinds,
+            )];
+            r.push(HRow::Header("Mouse"));
+            r.extend(
+                [
+                    Opt::Sensitivity,
+                    Opt::WheelSensitivity,
+                    Opt::InvertY,
+                    Opt::DiscreteScroll,
+                ]
+                .map(HRow::Opt),
+            );
+            r.push(HRow::Header("Movement"));
+            r.extend([Opt::ToggleCrouch, Opt::ToggleSprint, Opt::AutoJump].map(HRow::Opt));
+            r
+        },
+    },
+    Section {
+        name: "Accessibility",
+        blurb: "Contrast, motion, text backgrounds and notifications.",
+        rows: |_| {
+            [
+                Opt::HighContrast,
+                Opt::MenuBlur,
+                Opt::TextBackgroundOpacity,
+                Opt::NotificationDisplayTime,
+                Opt::ShowSubtitles,
+                Opt::ViewBobbing,
+                Opt::ChatLineSpacing,
+            ]
+            .map(HRow::Opt)
+            .to_vec()
+        },
+    },
+    Section {
+        name: "Language",
+        blurb: "The game's language and its font.",
+        rows: |_| {
+            vec![
+                HRow::Page("Language", "", Page::Language),
+                HRow::Opt(Opt::ForceUnicode),
+                HRow::Opt(Opt::JapaneseGlyphs),
+            ]
+        },
+    },
+    Section {
+        name: "Chat",
+        blurb: "What chat shows and how it looks.",
+        rows: |_| {
+            [
+                Opt::ChatVisibility,
+                Opt::ChatColors,
+                Opt::ChatLinks,
+                Opt::ChatOpacity,
+                Opt::ChatScale,
+                Opt::ChatWidth,
+                Opt::ChatHeightFocused,
+                Opt::ChatHeightUnfocused,
+                Opt::AutoSuggestions,
+                Opt::ReducedDebugInfo,
+            ]
+            .map(HRow::Opt)
+            .to_vec()
+        },
+    },
+    Section {
+        name: "Interface",
+        blurb: "Menus and resource packs.",
+        rows: |_| {
+            vec![
+                HRow::Style,
+                HRow::Page("Resource packs", "Textures, sounds and fonts", Page::Packs),
+            ]
+        },
+    },
+];
+
+const NAV: u64 = id("options.nav", 0);
+const DONE: u64 = id("options.done", 0);
+const ROW: u64 = id("options.row", 0);
+const STYLE: u64 = id("options.style", 0);
+const ROW_H: f32 = 12.0 + CONTROL + 12.0;
+const HEADER_H: f32 = 40.0;
+
+/// Whether an option is an on/off switch, and its value.
+fn switch_value(opt: Opt, s: &Settings) -> Option<bool> {
+    Some(match opt {
+        Opt::InvertY => s.invert_y,
+        Opt::DiscreteScroll => s.discrete_scroll,
+        Opt::ViewBobbing => s.view_bobbing,
+        Opt::Vsync => s.vsync,
+        Opt::Fullscreen => s.fullscreen,
+        Opt::SmoothLighting => s.smooth_lighting,
+        Opt::EntityShadows => s.entity_shadows,
+        Opt::Vignette => s.vignette,
+        Opt::Autosave => s.autosave_indicator,
+        Opt::CutoutLeaves => s.cutout_leaves,
+        Opt::ImprovedTransparency => s.improved_transparency,
+        Opt::AutoJump => s.auto_jump,
+        Opt::ChatColors => s.chat_colors,
+        Opt::ChatLinks => s.chat_links,
+        Opt::AutoSuggestions => s.auto_suggestions,
+        Opt::ReducedDebugInfo => s.reduced_debug_info,
+        Opt::HighContrast => s.high_contrast,
+        Opt::ShowSubtitles => s.show_subtitles,
+        Opt::ForceUnicode => s.force_unicode,
+        Opt::JapaneseGlyphs => s.japanese_glyphs,
+        _ => return None,
+    })
+}
+/// The option's caption and value text, from its vanilla label
+/// ("Caption: Value") and its caption key.
+fn caption_value(opt: Opt, s: &Settings) -> (String, String) {
+    let label = opt.label(s).plain();
+    let caption = crate::text::Text::translate(opt.caption(), &[]).plain();
+    if let Some(rest) = label.strip_prefix(&caption) {
+        return (caption, rest.trim_start_matches([':', ' ']).to_owned());
+    }
+    match label.split_once(": ") {
+        Some((c, v)) => (c.to_owned(), v.to_owned()),
+        None => (caption, label),
+    }
+}
+/// What a click hit.
+enum Target {
+    Nav(usize),
+    Done,
+    Row(usize),
+    Slider(Opt, f32),
+    Style(usize),
+}
+impl OptionsUi {
+    /// Lay out (and draw, on a real frame) the Horizon options shell.
+    /// Returns the sliders' tracks (option, x, width) for dragging.
+    fn horizon_layout(&mut self, s: &Settings, ui: &mut Ui, backdrop: f32) -> Vec<(Opt, f32, f32)> {
+        let (w, h) = (ui.w, ui.h);
+        if self.in_world {
+            ui.atmosphere(0.45, 1.0);
+        } else {
+            if backdrop < 1.0 {
+                ui.cold_background(1.0 - backdrop);
+            }
+            ui.atmosphere(0.66, 1.0);
+        }
+        let section = self.section.min(SECTIONS.len() - 1);
+        // The sidebar.
+        ui.fill(0.0, 0.0, SIDEBAR, h, color::with_alpha(color::SIDEBAR, 0.8));
+        ui.vline(SIDEBAR - 1.0, 0.0, h, color::BORDER);
+        ui.text_line(
+            Face::Display,
+            22.0,
+            30.0,
+            22.0,
+            16.0,
+            color::TEXT,
+            "Options",
+        );
+        let names: Vec<&str> = SECTIONS.iter().map(|s| s.name).collect();
+        ui.sidebar_list(NAV, 12.0, 66.0, SIDEBAR - 24.0, &names, section);
+        let dy = h - 12.0 - CONTROL;
+        ui.button(
+            DONE,
+            [12.0, dy, SIDEBAR - 24.0, CONTROL],
+            "Done",
+            Button::Secondary,
+            true,
+        );
+        // The page fades in and rises 8 when the section changes.
+        let p = ui.tween(id("options.page", section as u64), 1.0, t::move_());
+        if self.section_shown != Some(section) {
+            self.section_shown = Some(section);
+            ui.restart(id("options.page", section as u64), 0.0, 1.0, t::move_());
+        }
+        let x = SIDEBAR + 48.0;
+        let cw = (w - x - 48.0).min(760.0);
+        ui.opacity = p;
+        ui.offset = (0.0, 8.0 * (1.0 - p));
+        let sec = &SECTIONS[section];
+        let mut y = 36.0;
+        y += ui.page_header(x, y, sec.name, sec.blurb) + 24.0;
+        let top = y;
+        let rows = (sec.rows)(s);
+        let content: f32 = rows
+            .iter()
+            .map(|r| {
+                if matches!(r, HRow::Header(_)) {
+                    HEADER_H
+                } else {
+                    ROW_H
+                }
+            })
+            .sum();
+        let bottom = h - 24.0;
+        let max = (content - (bottom - top)).max(0.0);
+        self.hscroll = self.hscroll.clamp(0.0, max);
+        y -= self.hscroll;
+        let vstart = ui.batch.vertices.len();
+        let hstart = ui.hits.len();
+        let mut sliders = Vec::new();
+        ui.divider(x, y, cw);
+        let control_x = x + cw;
+        for (i, row) in rows.iter().enumerate() {
+            match *row {
+                HRow::Header(label) => {
+                    ui.text(Face::Medium, SMALL, x, y + 18.0, color::FAINT, label);
+                    y += HEADER_H;
+                    ui.divider(x, y, cw);
+                    continue;
+                }
+                HRow::Opt(opt) => {
+                    let (caption, value) = caption_value(opt, s);
+                    let cy = y + ROW_H / 2.0;
+                    if let Some(on) = switch_value(opt, s) {
+                        ui.row(x, y, &caption, "", 0.0);
+                        ui.switch(ROW + i as u64, control_x, cy, on);
+                    } else if let Kind::Slider(v) = opt.kind(s) {
+                        let sw = 220.0_f32.min(cw - ROW_LABEL - 200.0).max(80.0);
+                        ui.row(x, y, &caption, &value, cw - ROW_LABEL - 16.0 - sw - 24.0);
+                        let sx = control_x - sw - 8.0;
+                        ui.slider(ROW + i as u64, sx, cy, sw, v);
+                        sliders.push((opt, sx, sw));
+                    } else {
+                        ui.row(x, y, &caption, "", 0.0);
+                        let bw = ui.button_width(&value, false).max(96.0);
+                        ui.button(
+                            ROW + i as u64,
+                            [control_x - bw, y + 12.0, bw, CONTROL],
+                            &value,
+                            Button::Secondary,
+                            true,
+                        );
+                    }
+                }
+                HRow::Page(label, value, _) => {
+                    let value = if value.is_empty() {
+                        self.languages
+                            .iter()
+                            .find(|l| l.code == s.language)
+                            .map_or_else(|| s.language.clone(), |l| l.label())
+                    } else {
+                        value.to_owned()
+                    };
+                    ui.row(x, y, label, &value, cw - ROW_LABEL - 140.0);
+                    let bw = ui.button_width("Change…", false);
+                    let open = if label == "Language" {
+                        "Change…"
+                    } else {
+                        "Open…"
+                    };
+                    let bw = bw.max(ui.button_width(open, false));
+                    ui.button(
+                        ROW + i as u64,
+                        [control_x - bw, y + 12.0, bw, CONTROL],
+                        open,
+                        Button::Secondary,
+                        true,
+                    );
+                }
+                HRow::Style => {
+                    ui.row(x, y, "Menu style", "", 0.0);
+                    let labels = ["Horizon", "Classic"];
+                    let probe = ui.segmented(STYLE, -10_000.0, -10_000.0, &labels, 0);
+                    let selected = usize::from(t::style() == MenuStyle::Classic);
+                    ui.segmented(STYLE, control_x - probe, y + 12.0 - 3.0, &labels, selected);
+                }
+            }
+            y += ROW_H;
+            ui.divider(x, y, cw);
+        }
+        // Clip the rows to the page below the header, like the launcher's scroll view.
+        let (ox, oy) = ui.offset;
+        let scale = ui.batch.scale;
+        let k = ui.density / scale;
+        let (y0, y1) = ((top - 1.0 + oy) * k, (bottom + oy) * k);
+        ui.batch.clip_since(vstart, 0.0, y0, ui.batch.width, y1);
+        let (cy0, cy1) = (top - 1.0 + oy, bottom + oy);
+        let kept: Vec<_> = ui
+            .hits
+            .drain(hstart..)
+            .filter(|h| h.rect[1] >= cy0 && h.rect[3] <= cy1)
+            .collect();
+        ui.hits.extend(kept);
+        if max > 0.0 {
+            // A thin scroll indicator.
+            let track = bottom - top;
+            let bar = (track * track / (track + max)).max(24.0);
+            let by = top + (track - bar) * (self.hscroll / max);
+            ui.rounded(
+                x + cw + 16.0,
+                by,
+                3.0,
+                bar,
+                1.5,
+                color::with_alpha(color::MUTED, 0.35),
+            );
+        }
+        let _ = ox;
+        ui.opacity = 1.0;
+        ui.offset = (0.0, 0.0);
+        sliders
+    }
+    pub(crate) fn draw_horizon(
+        &mut self,
+        s: &Settings,
+        batch: &mut HudBatch,
+        atlas: &HudAtlas,
+        cursor: (f32, f32),
+    ) {
+        let mut ui = Ui::new(atlas, batch, cursor);
+        let backdrop = t::backdrop();
+        self.horizon_layout(s, &mut ui, backdrop);
+        ui.finish();
+    }
+    fn horizon_target(&mut self, s: &Settings, atlas: &HudAtlas, x: f32, y: f32) -> Option<Target> {
+        let mut batch = t::scratch_batch();
+        let mut ui = Ui::dry(atlas, &mut batch, (x, y));
+        let sliders = self.horizon_layout(s, &mut ui, 1.0);
+        let hit = ui.hit((x, y))?;
+        let section = self.section.min(SECTIONS.len() - 1);
+        if (NAV..NAV + SECTIONS.len() as u64).contains(&hit) {
+            return Some(Target::Nav((hit - NAV) as usize));
+        }
+        if hit == DONE {
+            return Some(Target::Done);
+        }
+        if hit == STYLE || hit == STYLE + 1 {
+            return Some(Target::Style((hit - STYLE) as usize));
+        }
+        let i = hit.checked_sub(ROW)? as usize;
+        let rows = (SECTIONS[section].rows)(s);
+        if let Some(HRow::Opt(opt)) = rows.get(i)
+            && let Some(&(_, sx, sw)) = sliders.iter().find(|(o, ..)| o == opt)
+        {
+            let v = t::slider_value(&ui, sx, sw, x);
+            return Some(Target::Slider(*opt, v));
+        }
+        (i < rows.len()).then_some(Target::Row(i))
+    }
+    /// A click (or a drag with the button held) on the Horizon shell.
+    pub(crate) fn click_horizon(
+        &mut self,
+        s: &mut Settings,
+        atlas: &HudAtlas,
+        x: f32,
+        y: f32,
+        drag: bool,
+        right: bool,
+    ) -> Vec<Event> {
+        let mut events = Vec::new();
+        if drag {
+            if let Some(opt) = self.dragging {
+                let mut batch = t::scratch_batch();
+                let mut ui = Ui::dry(atlas, &mut batch, (x, y));
+                let sliders = self.horizon_layout(s, &mut ui, 1.0);
+                if let Some(&(_, sx, sw)) = sliders.iter().find(|(o, ..)| *o == opt) {
+                    opt.set_slider(s, t::slider_value(&ui, sx, sw, x));
+                    if opt == Opt::Preset {
+                        apply_preset(s);
+                    }
+                    events.push(Event::Changed);
+                }
+            }
+            return events;
+        }
+        match self.horizon_target(s, atlas, x, y) {
+            Some(Target::Nav(i)) => {
+                self.section = i;
+                self.hscroll = 0.0;
+            }
+            Some(Target::Done) => events.extend(self.back(s)),
+            Some(Target::Style(i)) => {
+                t::set_style(if i == 1 {
+                    MenuStyle::Classic
+                } else {
+                    MenuStyle::Horizon
+                });
+                if let Ok(dir) = std::env::current_dir() {
+                    t::save_preferences(&dir);
+                }
+            }
+            Some(Target::Slider(opt, v)) => {
+                self.dragging = Some(opt);
+                opt.set_slider(s, v);
+                if opt == Opt::Preset {
+                    apply_preset(s);
+                }
+                events.push(Event::Changed);
+            }
+            Some(Target::Row(i)) => {
+                let section = self.section.min(SECTIONS.len() - 1);
+                match (SECTIONS[section].rows)(s).get(i) {
+                    Some(HRow::Opt(opt)) => {
+                        opt.cycle(s, right);
+                        if *opt == Opt::Preset {
+                            apply_preset(s);
+                        }
+                        events.push(Event::Changed);
+                    }
+                    Some(HRow::Page(_, _, page)) => self.open_page(*page),
+                    _ => {}
+                }
+            }
+            None => {}
+        }
+        events
+    }
+    pub(crate) fn scroll_horizon(&mut self, amount: f32) {
+        self.hscroll -= amount * 40.0;
+    }
+}

crates/horizon-client/src/options_ui.rs

@@ -92,13 +92,13 @@ fn chat_px(caption: &str, px: f32) -> Text {
         &[tr(caption), Text::literal((px as i32).to_string())],
     )
 }
-enum Kind {
+pub(crate) enum Kind {
     /// Slider position 0..1.
     Slider(f32),
     Cycle,
 }
 impl Opt {
-    fn caption(self) -> &'static str {
+    pub(crate) fn caption(self) -> &'static str {
         match self {
             Opt::Fov => "options.fov",
             Opt::RenderDistance => "options.renderDistance",
@@ -155,7 +155,7 @@ impl Opt {
             Opt::JapaneseGlyphs => "options.japaneseGlyphVariants",
         }
     }
-    fn kind(self, s: &Settings) -> Kind {
+    pub(crate) fn kind(self, s: &Settings) -> Kind {
         let unit = |v: f32, lo: f32, hi: f32| Kind::Slider(((v - lo) / (hi - lo)).clamp(0.0, 1.0));
         match self {
             Opt::Fov => unit(s.fov, 30.0, 110.0),
@@ -590,7 +590,12 @@ pub enum Event {
 pub struct OptionsUi {
     pub stack: Vec<Page>,
     scroll: f32,
-    dragging: Option<Opt>,
+    pub(crate) dragging: Option<Opt>,
+    /// Horizon style: the selected sidebar section, the one last drawn and
+    /// the rows' scroll in dp (`options_horizon`).
+    pub section: usize,
+    pub(crate) section_shown: Option<usize>,
+    pub(crate) hscroll: f32,
     /// Key Binds: the mapping waiting for a key.
     pub selected_key: Option<&'static str>,
     pub languages: Vec<LanguageInfo>,
@@ -615,6 +620,9 @@ impl Default for OptionsUi {
             stack: vec![Page::Main],
             scroll: 0.0,
             dragging: None,
+            section: 0,
+            section_shown: None,
+            hscroll: 0.0,
             selected_key: None,
             languages: Vec::new(),
             language_choice: None,
@@ -693,6 +701,10 @@ impl OptionsUi {
         self.in_world = in_world;
         self.selected_key = None;
     }
+    /// Open one of vanilla's pages over the current one.
+    pub(crate) fn open_page(&mut self, page: Page) {
+        self.push(page);
+    }
     fn push(&mut self, page: Page) {
         self.stack.push(page);
         self.scroll = 0.0;
@@ -1175,6 +1187,10 @@ impl OptionsUi {
         cursor: (f32, f32),
     ) {
         let (w, h) = (batch.width, batch.height);
+        if crate::ui_theme::horizon() && self.page() == Page::Main {
+            self.draw_horizon(s, batch, atlas, cursor);
+            return;
+        }
         if self.page() == Page::Packs {
             ui::menu_background(batch, atlas, 0.0, 0.0, w, h, self.in_world);
             let blink = self.pack_focus.elapsed().as_millis() as u64;
@@ -1324,6 +1340,9 @@ impl OptionsUi {
         drag: bool,
         right: bool,
     ) -> Vec<Event> {
+        if crate::ui_theme::horizon() && self.page() == Page::Main {
+            return self.click_horizon(s, atlas, x, y, drag, right);
+        }
         if self.page() == Page::Packs {
             let mut events = Vec::new();
             if drag || right {
@@ -1427,6 +1446,10 @@ impl OptionsUi {
     }
     /// The mouse wheel at the cursor.
     pub fn scroll_at(&mut self, cursor: (f32, f32), amount: f32) {
+        if crate::ui_theme::horizon() && self.page() == Page::Main {
+            self.scroll_horizon(amount);
+            return;
+        }
         match &mut self.pack_screen {
             Some(p) if self.stack.last() == Some(&Page::Packs) => {
                 p.scroll(cursor.0 as f64, cursor.1 as f64, amount as f64)

crates/horizon-client/src/post.rs

@@ -0,0 +1,273 @@
+//! The menus' backdrop treatment (`ui_theme`'s Horizon style): the finished
+//! world frame is blurred (dual Kawase: three halvings down, back up) and
+//! colour graded before the HUD is drawn over it. Needs a swapchain that can
+//! be copied from; without one the frame is left as it is.
+
+/// How the frame under a Horizon-style menu is treated.
+#[derive(Clone, Copy, Debug, PartialEq)]
+pub struct PostGrade {
+    /// Colour multiplier and lift (`c * tint + lift`).
+    pub tint: [f32; 3],
+    pub lift: [f32; 3],
+    /// Toward grey, 0..1.
+    pub desaturate: f32,
+    /// Darkening toward the corners, 0..1.
+    pub vignette: f32,
+}
+impl PostGrade {
+    /// The title backdrop: icy, slightly lifted shadows.
+    pub const FROST: Self = Self {
+        tint: [0.62, 0.78, 1.0],
+        lift: [0.0, 0.01, 0.035],
+        desaturate: 0.45,
+        vignette: 0.5,
+    };
+    /// Behind the pause menu: the world stays recognisable.
+    pub const PAUSE: Self = Self {
+        tint: [0.8, 0.86, 0.98],
+        lift: [0.0, 0.004, 0.012],
+        desaturate: 0.25,
+        vignette: 0.3,
+    };
+}
+#[repr(C)]
+#[derive(Clone, Copy, bytemuck::Pod, bytemuck::Zeroable)]
+struct Uniform {
+    texel: [f32; 4],
+    tint: [f32; 4],
+    lift: [f32; 4],
+    params: [f32; 4],
+}
+const LEVELS: usize = 3;
+pub struct Post {
+    layout: wgpu::BindGroupLayout,
+    down: wgpu::RenderPipeline,
+    up: wgpu::RenderPipeline,
+    finish: wgpu::RenderPipeline,
+    sampler: wgpu::Sampler,
+    /// The copied frame, then the halvings.
+    levels: Vec<(wgpu::Texture, wgpu::TextureView, [u32; 2])>,
+    uniforms: Vec<wgpu::Buffer>,
+    size: [u32; 2],
+    format: wgpu::TextureFormat,
+}
+impl Post {
+    pub fn new(device: &wgpu::Device, format: wgpu::TextureFormat) -> Self {
+        let shader = device.create_shader_module(wgpu::ShaderModuleDescriptor {
+            label: Some("Menu backdrop"),
+            source: wgpu::ShaderSource::Wgsl(include_str!("post.wgsl").into()),
+        });
+        let layout = device.create_bind_group_layout(&wgpu::BindGroupLayoutDescriptor {
+            label: Some("Menu backdrop bindings"),
+            entries: &[
+                wgpu::BindGroupLayoutEntry {
+                    binding: 0,
+                    visibility: wgpu::ShaderStages::FRAGMENT,
+                    ty: wgpu::BindingType::Texture {
+                        sample_type: wgpu::TextureSampleType::Float { filterable: true },
+                        view_dimension: wgpu::TextureViewDimension::D2,
+                        multisampled: false,
+                    },
+                    count: None,
+                },
+                wgpu::BindGroupLayoutEntry {
+                    binding: 1,
+                    visibility: wgpu::ShaderStages::FRAGMENT,
+                    ty: wgpu::BindingType::Sampler(wgpu::SamplerBindingType::Filtering),
+                    count: None,
+                },
+                wgpu::BindGroupLayoutEntry {
+                    binding: 2,
+                    visibility: wgpu::ShaderStages::FRAGMENT,
+                    ty: wgpu::BindingType::Buffer {
+                        ty: wgpu::BufferBindingType::Uniform,
+                        has_dynamic_offset: false,
+                        min_binding_size: None,
+                    },
+                    count: None,
+                },
+            ],
+        });
+        let pipeline_layout = device.create_pipeline_layout(&wgpu::PipelineLayoutDescriptor {
+            label: Some("Menu backdrop"),
+            bind_group_layouts: &[Some(&layout)],
+            ..Default::default()
+        });
+        let pipeline = |entry: &str| {
+            device.create_render_pipeline(&wgpu::RenderPipelineDescriptor {
+                label: Some("Menu backdrop pass"),
+                layout: Some(&pipeline_layout),
+                vertex: wgpu::VertexState {
+                    module: &shader,
+                    entry_point: Some("vs_main"),
+                    buffers: &[],
+                    compilation_options: Default::default(),
+                },
+                fragment: Some(wgpu::FragmentState {
+                    module: &shader,
+                    entry_point: Some(entry),
+                    targets: &[Some(wgpu::ColorTargetState {
+                        format,
+                        blend: None,
+                        write_mask: wgpu::ColorWrites::ALL,
+                    })],
+                    compilation_options: Default::default(),
+                }),
+                primitive: Default::default(),
+                depth_stencil: None,
+                multisample: Default::default(),
+                multiview_mask: None,
+                cache: None,
+            })
+        };
+        let sampler = device.create_sampler(&wgpu::SamplerDescriptor {
+            label: Some("Menu backdrop"),
+            mag_filter: wgpu::FilterMode::Linear,
+            min_filter: wgpu::FilterMode::Linear,
+            address_mode_u: wgpu::AddressMode::ClampToEdge,
+            address_mode_v: wgpu::AddressMode::ClampToEdge,
+            ..Default::default()
+        });
+        let uniforms = (0..LEVELS * 2 + 1)
+            .map(|_| {
+                device.create_buffer(&wgpu::BufferDescriptor {
+                    label: Some("Menu backdrop pass"),
+                    size: std::mem::size_of::<Uniform>() as u64,
+                    usage: wgpu::BufferUsages::UNIFORM | wgpu::BufferUsages::COPY_DST,
+                    mapped_at_creation: false,
+                })
+            })
+            .collect();
+        Self {
+            down: pipeline("fs_down"),
+            up: pipeline("fs_up"),
+            finish: pipeline("fs_final"),
+            layout,
+            sampler,
+            levels: Vec::new(),
+            uniforms,
+            size: [0, 0],
+            format,
+        }
+    }
+    fn ensure(&mut self, device: &wgpu::Device, size: [u32; 2]) {
+        if self.size == size && !self.levels.is_empty() {
+            return;
+        }
+        self.size = size;
+        self.levels = (0..=LEVELS)
+            .map(|i| {
+                let s = [(size[0] >> i).max(1), (size[1] >> i).max(1)];
+                let texture = device.create_texture(&wgpu::TextureDescriptor {
+                    label: Some("Menu backdrop level"),
+                    size: wgpu::Extent3d {
+                        width: s[0],
+                        height: s[1],
+                        depth_or_array_layers: 1,
+                    },
+                    mip_level_count: 1,
+                    sample_count: 1,
+                    dimension: wgpu::TextureDimension::D2,
+                    format: self.format,
+                    usage: wgpu::TextureUsages::TEXTURE_BINDING
+                        | wgpu::TextureUsages::RENDER_ATTACHMENT
+                        | wgpu::TextureUsages::COPY_DST,
+                    view_formats: &[],
+                });
+                let view = texture.create_view(&Default::default());
+                (texture, view, s)
+            })
+            .collect();
+    }
+    fn pass(
+        &self,
+        device: &wgpu::Device,
+        queue: &wgpu::Queue,
+        encoder: &mut wgpu::CommandEncoder,
+        pipeline: &wgpu::RenderPipeline,
+        (from, uniform): (usize, usize),
+        target: &wgpu::TextureView,
+        data: Uniform,
+    ) {
+        let (_, view, s) = &self.levels[from];
+        let mut data = data;
+        data.texel = [0.5 / s[0] as f32, 0.5 / s[1] as f32, 0.0, 0.0];
+        queue.write_buffer(&self.uniforms[uniform], 0, bytemuck::bytes_of(&data));
+        let group = device.create_bind_group(&wgpu::BindGroupDescriptor {
+            label: Some("Menu backdrop pass"),
+            layout: &self.layout,
+            entries: &[
+                wgpu::BindGroupEntry {
+                    binding: 0,
+                    resource: wgpu::BindingResource::TextureView(view),
+                },
+                wgpu::BindGroupEntry {
+                    binding: 1,
+                    resource: wgpu::BindingResource::Sampler(&self.sampler),
+                },
+                wgpu::BindGroupEntry {
+                    binding: 2,
+                    resource: self.uniforms[uniform].as_entire_binding(),
+                },
+            ],
+        });
+        let attachments = [Some(wgpu::RenderPassColorAttachment {
+            view: target,
+            resolve_target: None,
+            depth_slice: None,
+            ops: wgpu::Operations {
+                load: wgpu::LoadOp::Clear(wgpu::Color::BLACK),
+                store: wgpu::StoreOp::Store,
+            },
+        })];
+        let mut pass = encoder.begin_render_pass(&wgpu::RenderPassDescriptor {
+            label: Some("Menu backdrop pass"),
+            color_attachments: &attachments,
+            ..Default::default()
+        });
+        pass.set_pipeline(pipeline);
+        pass.set_bind_group(0, &group, &[]);
+        pass.draw(0..3, 0..1);
+    }
+    /// Blur and grade `frame` (the swapchain texture) into `target`.
+    #[allow(clippy::too_many_arguments)]
+    pub fn apply(
+        &mut self,
+        device: &wgpu::Device,
+        queue: &wgpu::Queue,
+        encoder: &mut wgpu::CommandEncoder,
+        frame: &wgpu::Texture,
+        target: &wgpu::TextureView,
+        size: [u32; 2],
+        grade: &PostGrade,
+    ) {
+        self.ensure(device, size);
+        encoder.copy_texture_to_texture(
+            frame.as_image_copy(),
+            self.levels[0].0.as_image_copy(),
+            wgpu::Extent3d {
+                width: size[0],
+                height: size[1],
+                depth_or_array_layers: 1,
+            },
+        );
+        let data = Uniform {
+            texel: [0.0; 4],
+            tint: [grade.tint[0], grade.tint[1], grade.tint[2], 1.0],
+            lift: [grade.lift[0], grade.lift[1], grade.lift[2], 0.0],
+            params: [grade.desaturate, grade.vignette, 0.0, 0.0],
+        };
+        let mut u = 0;
+        for i in 1..=LEVELS {
+            let target = &self.levels[i].1;
+            self.pass(device, queue, encoder, &self.down, (i - 1, u), target, data);
+            u += 1;
+        }
+        for i in (1..LEVELS).rev() {
+            let target = &self.levels[i].1;
+            self.pass(device, queue, encoder, &self.up, (i + 1, u), target, data);
+            u += 1;
+        }
+        self.pass(device, queue, encoder, &self.finish, (1, u), target, data);
+    }
+}

crates/horizon-client/src/post.wgsl

@@ -0,0 +1,51 @@
+// Menu backdrop: dual-Kawase blur (down and up passes) and a cold colour grade.
+struct Post {
+    // Half a source texel (u, v), unused, unused.
+    texel: vec4<f32>,
+    // Multiplier and lift of the grade.
+    tint: vec4<f32>,
+    lift: vec4<f32>,
+    // Desaturation, vignette, unused, unused.
+    params: vec4<f32>,
+}
+@group(0) @binding(0) var src: texture_2d<f32>;
+@group(0) @binding(1) var samp: sampler;
+@group(0) @binding(2) var<uniform> post: Post;
+struct Out {
+    @builtin(position) clip: vec4<f32>,
+    @location(0) uv: vec2<f32>,
+}
+@vertex fn vs_main(@builtin(vertex_index) i: u32) -> Out {
+    let p = vec2<f32>(f32((i << 1u) & 2u), f32(i & 2u));
+    var out: Out;
+    out.clip = vec4(p * 2.0 - 1.0, 0.0, 1.0);
+    out.uv = vec2(p.x, 1.0 - p.y);
+    return out;
+}
+fn s(uv: vec2<f32>) -> vec3<f32> {
+    return textureSampleLevel(src, samp, uv, 0.0).rgb;
+}
+@fragment fn fs_down(in: Out) -> @location(0) vec4<f32> {
+    let h = post.texel.xy;
+    let c = s(in.uv) * 4.0 + s(in.uv - h) + s(in.uv + h) + s(in.uv + vec2(h.x, -h.y)) + s(in.uv - vec2(h.x, -h.y));
+    return vec4(c / 8.0, 1.0);
+}
+fn up(uv: vec2<f32>) -> vec3<f32> {
+    let h = post.texel.xy;
+    var c = s(uv + vec2(-h.x * 2.0, 0.0)) + s(uv + vec2(h.x * 2.0, 0.0));
+    c += s(uv + vec2(0.0, -h.y * 2.0)) + s(uv + vec2(0.0, h.y * 2.0));
+    c += (s(uv + vec2(-h.x, h.y)) + s(uv + vec2(h.x, h.y)) + s(uv + vec2(-h.x, -h.y)) + s(uv + vec2(h.x, -h.y))) * 2.0;
+    return c / 12.0;
+}
+@fragment fn fs_up(in: Out) -> @location(0) vec4<f32> {
+    return vec4(up(in.uv), 1.0);
+}
+@fragment fn fs_final(in: Out) -> @location(0) vec4<f32> {
+    var c = up(in.uv);
+    let l = dot(c, vec3(0.2126, 0.7152, 0.0722));
+    c = mix(c, vec3(l), post.params.x);
+    c = c * post.tint.rgb + post.lift.rgb;
+    let d = length((in.uv - 0.5) * vec2(1.25, 1.0));
+    c *= 1.0 - post.params.y * smoothstep(0.35, 0.95, d);
+    return vec4(clamp(c, vec3(0.0), vec3(1.0)), 1.0);
+}

crates/horizon-client/src/title.rs

@@ -50,6 +50,12 @@ pub struct Title {
     pub mode: Mode,
     pub saves: PathBuf,
     pub started: std::time::Instant,
+    /// The mode last drawn and when it appeared (Horizon's screen fades).
+    shown: std::cell::Cell<(std::mem::Discriminant<Mode>, std::time::Instant)>,
+    /// The launcher-style opening (Horizon style, first title of the session).
+    pub opening: std::cell::Cell<Option<crate::front::Opening>>,
+    /// The saves listed for Home, re-read every couple of seconds.
+    recent: std::cell::RefCell<Option<(std::time::Instant, Vec<WorldEntry>)>>,
 }
 struct Button {
     x: f32,
@@ -96,10 +102,78 @@ pub fn list_worlds(saves: &Path) -> Vec<WorldEntry> {
 }
 impl Title {
     pub fn new(saves: PathBuf) -> Self {
+        let mode = Mode::Main;
+        let now = std::time::Instant::now();
         Self {
-            mode: Mode::Main,
+            shown: std::cell::Cell::new((std::mem::discriminant(&mode), now)),
+            mode,
             saves,
-            started: std::time::Instant::now(),
+            started: now,
+            opening: std::cell::Cell::new(None),
+            recent: std::cell::RefCell::new(None),
+        }
+    }
+    /// The worlds, newest first, cached for two seconds (drawn every frame).
+    pub fn recent_worlds(&self) -> Vec<WorldEntry> {
+        let mut recent = self.recent.borrow_mut();
+        match &*recent {
+            Some((at, worlds)) if at.elapsed().as_secs() < 2 => worlds.clone(),
+            _ => {
+                let worlds = list_worlds(&self.saves);
+                *recent = Some((std::time::Instant::now(), worlds.clone()));
+                worlds
+            }
+        }
+    }
+    /// When the current mode first appeared.
+    pub fn entered(&self) -> std::time::Instant {
+        let now = std::mem::discriminant(&self.mode);
+        let (mode, at) = self.shown.get();
+        if mode == now {
+            return at;
+        }
+        let at = std::time::Instant::now();
+        self.shown.set((now, at));
+        at
+    }
+    /// Create New World: the folder name and options (FileUtil.findAvailableName).
+    pub fn create_action(&self) -> Action {
+        let Mode::Create {
+            name,
+            seed,
+            creative,
+            ..
+        } = &self.mode
+        else {
+            return Action::None;
+        };
+        let base: String = name
+            .chars()
+            .map(|c| {
+                if c.is_alphanumeric() || c == ' ' || c == '-' || c == '_' {
+                    c
+                } else {
+                    '_'
+                }
+            })
+            .collect();
+        let base = if base.trim().is_empty() {
+            "World".to_owned()
+        } else {
+            base.trim().to_owned()
+        };
+        // FileUtil.findAvailableName: append (n) until unused.
+        let mut folder = base.clone();
+        let mut n = 1;
+        while self.saves.join(&folder).exists() {
+            folder = format!("{base} ({n})");
+            n += 1;
+        }
+        Action::Create {
+            folder,
+            name: name.clone(),
+            seed: parse_seed(seed),
+            creative: *creative,
         }
     }
     fn buttons(&self, w: f32, h: f32) -> Vec<Button> {
@@ -446,44 +520,7 @@ impl Title {
                 *creative = !*creative;
                 Action::None
             }
-            (
-                Mode::Create {
-                    name,
-                    seed,
-                    creative,
-                    ..
-                },
-                Some(21),
-            ) => {
-                let base: String = name
-                    .chars()
-                    .map(|c| {
-                        if c.is_alphanumeric() || c == ' ' || c == '-' || c == '_' {
-                            c
-                        } else {
-                            '_'
-                        }
-                    })
-                    .collect();
-                let base = if base.trim().is_empty() {
-                    "World".to_owned()
-                } else {
-                    base.trim().to_owned()
-                };
-                // FileUtil.findAvailableName: append (n) until unused.
-                let mut folder = base.clone();
-                let mut n = 1;
-                while self.saves.join(&folder).exists() {
-                    folder = format!("{base} ({n})");
-                    n += 1;
-                }
-                Action::Create {
-                    folder,
-                    name: name.clone(),
-                    seed: parse_seed(seed),
-                    creative: *creative,
-                }
-            }
+            (Mode::Create { .. }, Some(21)) => self.create_action(),
             (Mode::Create { .. }, Some(22)) => {
                 self.mode = Mode::Select {
                     worlds: list_worlds(&self.saves),
@@ -510,6 +547,7 @@ impl Title {
         if let Mode::Create {
             name, seed, focus, ..
         } = &mut self.mode
+            && *focus < 2
         {
             let field = if *focus == 0 { name } else { seed };
             for c in text.chars().filter(|c| !c.is_control()) {
@@ -526,6 +564,7 @@ impl Title {
         if let Mode::Create {
             name, seed, focus, ..
         } = &mut self.mode
+            && *focus < 2
         {
             let field = if *focus == 0 { name } else { seed };
             field.pop();
@@ -554,6 +593,10 @@ impl Title {
         };
     }
 }
+/// `yyyy/MM/dd HH:mm` (UTC) for a modification time in Unix seconds.
+pub fn date_label(secs: u64) -> String {
+    date_string(secs)
+}
 fn date_string(secs: u64) -> String {
     // Civil date from Unix time (days-from-civil inverse), UTC.
     let days = (secs / 86400) as i64;

crates/horizon-theme/Cargo.toml

@@ -0,0 +1,8 @@
+[package]
+name = "horizon-theme"
+version = "0.1.0"
+edition = "2021"
+license = "MIT"
+description = "Horizon's design tokens and fonts, shared by the launcher and the game's menus"
+
+[dependencies]

crates/horizon-theme/src/lib.rs

@@ -0,0 +1,120 @@
+//! Horizon's design tokens, shared by the launcher (`launcher/src/theme.rs`)
+//! and the game's menus (`horizon-client`'s `ui_theme`), so the two read as
+//! one product: change a value here and both follow.
+//!
+//! One neutral palette in two appearances and one accent. Spacing follows
+//! 4/8/12/16/24/32. Type: Geist for the interface, Instrument Serif for
+//! titles, Geist Mono for consoles and commands, all bundled here under the
+//! SIL Open Font License (`fonts/OFL-*.txt`). Five sizes: 12, 13, 15, 28 and 56.
+//! Colours are `0xRRGGBB`; sizes are in logical pixels.
+use std::time::Duration;
+
+pub const FONT: &str = "Geist";
+pub const DISPLAY: &str = "Instrument Serif";
+pub const MONO: &str = "Geist Mono";
+
+/// The bundled font files.
+pub mod fonts {
+    pub const GEIST_REGULAR: &[u8] = include_bytes!("../fonts/Geist-Regular.ttf");
+    pub const GEIST_MEDIUM: &[u8] = include_bytes!("../fonts/Geist-Medium.ttf");
+    pub const GEIST_SEMIBOLD: &[u8] = include_bytes!("../fonts/Geist-SemiBold.ttf");
+    pub const GEIST_MONO: &[u8] = include_bytes!("../fonts/GeistMono-Regular.ttf");
+    pub const INSTRUMENT_SERIF: &[u8] = include_bytes!("../fonts/InstrumentSerif-Regular.ttf");
+}
+
+pub const SMALL: f32 = 12.;
+pub const BODY: f32 = 13.;
+pub const LARGE: f32 = 15.;
+pub const TITLE: f32 = 28.;
+pub const HERO: f32 = 56.;
+/// The opening's wordmark.
+pub const WORDMARK: f32 = 96.;
+
+/// The spacing scale.
+pub const SPACE: [f32; 6] = [4., 8., 12., 16., 24., 32.];
+
+/// Corner radii: buttons, fields, nav items and rows; segments inside a
+/// segmented control; the segmented control's frame; menus and cards.
+pub const RADIUS: f32 = 6.;
+pub const RADIUS_SEGMENT: f32 = 5.;
+pub const RADIUS_GROUP: f32 = 7.;
+pub const RADIUS_CARD: f32 = 8.;
+/// Dividers and borders are one pixel.
+pub const HAIRLINE: f32 = 1.;
+
+/// Control heights: buttons and nav items, segments, the large Play button.
+pub const CONTROL: f32 = 30.;
+pub const SEGMENT: f32 = 26.;
+pub const CONTROL_LARGE: f32 = 40.;
+/// A pressed primary button's opacity (secondary and ghost: `PRESSED_SOFT`).
+pub const PRESSED: f32 = 0.82;
+pub const PRESSED_SOFT: f32 = 0.8;
+/// Disabled controls' opacity.
+pub const DISABLED: f32 = 0.4;
+/// The hover layer of a primary button: white at this opacity.
+pub const PRIMARY_HOVER: f32 = 0.10;
+/// Sidebar width and the label column of settings rows.
+pub const SIDEBAR: f32 = 200.;
+pub const ROW_LABEL: f32 = 150.;
+
+/// Motion: short and eased out, never bouncy.
+pub const QUICK: Duration = Duration::from_millis(160);
+pub const MOVE: Duration = Duration::from_millis(240);
+/// The opening: the wordmark holds, then the interface appears.
+pub const OPENING_HOLD: Duration = Duration::from_millis(1400);
+pub const OPENING_MAX: Duration = Duration::from_millis(2500);
+pub const OPENING_REVEAL: Duration = Duration::from_millis(800);
+
+/// GPUI's `ease_out_quint`, used for hovers, the sliding selection and page changes.
+pub fn ease_out_quint(t: f32) -> f32 {
+    1. - (1. - t.clamp(0., 1.)).powi(5)
+}
+pub fn ease_out_cubic(t: f32) -> f32 {
+    1. - (1. - t.clamp(0., 1.)).powi(3)
+}
+
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub struct Palette {
+    pub bg: u32,
+    pub sidebar: u32,
+    pub raised: u32,
+    pub hover: u32,
+    pub border: u32,
+    pub text: u32,
+    pub muted: u32,
+    pub faint: u32,
+    pub accent: u32,
+    pub on_accent: u32,
+    pub danger: u32,
+    pub dark: bool,
+}
+
+pub const DARK: Palette = Palette {
+    bg: 0x111113,
+    sidebar: 0x0c0c0d,
+    raised: 0x1a1a1d,
+    hover: 0x202024,
+    border: 0x26262a,
+    text: 0xe8e8ea,
+    muted: 0x9a9aa1,
+    faint: 0x626269,
+    accent: 0x7c5cc4,
+    on_accent: 0xffffff,
+    danger: 0xd9705f,
+    dark: true,
+};
+
+pub const LIGHT: Palette = Palette {
+    bg: 0xfcfcfb,
+    sidebar: 0xf4f4f2,
+    raised: 0xf2f2f0,
+    hover: 0xebebe8,
+    border: 0xe3e3df,
+    text: 0x19191b,
+    muted: 0x63636a,
+    faint: 0x9a9a9f,
+    accent: 0x6a4bb3,
+    on_accent: 0xffffff,
+    danger: 0xb84a3a,
+    dark: false,
+};

docs/README.md

@@ -7,6 +7,7 @@ To play, use [the launcher](../launcher/README.md). These pages are for develope
 - [Build from source](../README.md#build-from-source): your own copy of the game, resource preparation, `cargo run`.
 - [Native client](native-client.md): options, controls, the dedicated server, `horizon-ctl` scripting, packaging, architecture.
 - [Launcher](../launcher/README.md): installs, updates and starts builds; its CLI and MCP server; releasing it.
+- Menus: the title, world list, create world, multiplayer, options and pause screens share the launcher's design tokens and fonts (`crates/horizon-theme`), drawn by `ui_theme` over a live frozen backdrop (`game/backdrop.rs`, blurred and graded by `post.rs`). Options → Interface → Menu style switches to vanilla's screens (Classic, kept in `horizon.txt`; `HORIZON_MENU_STYLE=horizon|classic` overrides it, and scripted runs default to Classic). [Title](media/menu-title.png) ([webm](media/menu-title.webm)), [worlds](media/menu-worlds.png), [options](media/menu-options.png), [pause](media/menu-pause.png).
 
 ## Parity
 

launcher/Cargo.lock

@@ -2571,6 +2571,7 @@ dependencies = [
  "dirs 5.0.1",
  "flate2",
  "gpui",
+ "horizon-theme",
  "image",
  "pulldown-cmark",
  "self-replace",
@@ -2581,6 +2582,10 @@ dependencies = [
  "zip",
 ]
 
+[[package]]
+name = "horizon-theme"
+version = "0.1.0"
+
 [[package]]
 name = "http"
 version = "1.5.0"

launcher/Cargo.toml

@@ -20,6 +20,7 @@ dirs = "5"
 self-replace = "1"
 image = { version = "0.25", default-features = false, features = ["jpeg"] }
 clap = { version = "4", features = ["derive"] }
+horizon-theme = { path = "../crates/horizon-theme" }
 
 [profile.release]
 strip = true

launcher/README.md

@@ -87,7 +87,7 @@ workflow builds all three platforms on every push to the `launcher` branch.
 
     cargo test --lib    # tag separation, version order, update selection, notes as text
 
-Geist, Geist Mono and Instrument Serif (SIL Open Font License, `assets/fonts/OFL-*.txt`) are
+Geist, Geist Mono and Instrument Serif (SIL Open Font License, `crates/horizon-theme/fonts/OFL-*.txt`, shared with the game's menus) are
 bundled so the type is the same on every platform.
 
 Background image (`assets/background.jpg`): backgrounds.supply (free preview), licence to confirm before release.

launcher/src/main.rs

@@ -53,9 +53,9 @@ enum SelfUpdate {
 
 /// The opening: the wordmark over the image holds at least `OPENING_HOLD` (until the release
 /// list is in, at most `OPENING_MAX`), then the launcher appears over `OPENING_REVEAL`.
-const OPENING_HOLD: Duration = Duration::from_millis(1400);
-const OPENING_MAX: Duration = Duration::from_millis(2500);
-const OPENING_REVEAL: Duration = Duration::from_millis(800);
+const OPENING_HOLD: Duration = horizon_theme::OPENING_HOLD;
+const OPENING_MAX: Duration = horizon_theme::OPENING_MAX;
+const OPENING_REVEAL: Duration = horizon_theme::OPENING_REVEAL;
 
 /// The phase of the opening at one moment: how far the reveal has gone, 0 to 1.
 struct Opening {
@@ -78,7 +78,7 @@ fn background_image() -> Arc<RenderImage> {
 }
 
 fn ease_out_cubic(x: f32) -> f32 {
-    1. - (1. - x.clamp(0., 1.)).powi(3)
+    horizon_theme::ease_out_cubic(x)
 }
 
 /// How often the launcher looks for new releases while it is open.
@@ -560,7 +560,7 @@ fn button(id: impl Into<SharedString>, label: impl Into<SharedString>, kind: Kin
     let id: SharedString = id.into();
     let t = *t;
     let hover = match kind {
-        Kind::Primary => gpui::white().opacity(0.10),
+        Kind::Primary => gpui::white().opacity(theme::PRIMARY_HOVER),
         _ => t.hover,
     };
     let base = div()
@@ -570,19 +570,19 @@ fn button(id: impl Into<SharedString>, label: impl Into<SharedString>, kind: Kin
         .flex_none()
         .items_center()
         .justify_center()
-        .h(px(30.))
+        .h(px(theme::CONTROL))
         .px(px(12.))
-        .rounded(px(6.))
+        .rounded(px(theme::RADIUS))
         .text_size(px(theme::BODY))
         .font_weight(FontWeight::MEDIUM)
         .cursor_pointer()
-        .child(hover_layer(&id, hover, 6.))
+        .child(hover_layer(&id, hover, theme::RADIUS))
         .child(div().relative().child(label.into()));
     let base = track_hover(base, id);
     match kind {
-        Kind::Primary => base.bg(t.accent).text_color(t.on_accent).active(|s| s.opacity(0.82)),
-        Kind::Secondary => base.border_1().border_color(t.border).bg(t.raised).text_color(t.text).active(|s| s.opacity(0.8)),
-        Kind::Ghost => base.text_color(t.muted).hover(move |s| s.text_color(t.text)).active(|s| s.opacity(0.8)),
+        Kind::Primary => base.bg(t.accent).text_color(t.on_accent).active(|s| s.opacity(theme::PRESSED)),
+        Kind::Secondary => base.border_1().border_color(t.border).bg(t.raised).text_color(t.text).active(|s| s.opacity(theme::PRESSED_SOFT)),
+        Kind::Ghost => base.text_color(t.muted).hover(move |s| s.text_color(t.text)).active(|s| s.opacity(theme::PRESSED_SOFT)),
     }
 }
 
@@ -607,7 +607,7 @@ fn switch(id: &'static str, on: bool, t: &Theme) -> Stateful<Div> {
 }
 
 fn disabled(b: Stateful<Div>) -> Stateful<Div> {
-    b.opacity(0.4).cursor_default()
+    b.opacity(theme::DISABLED).cursor_default()
 }
 
 fn page_header(title: &str, description: &str, t: &Theme) -> Div {
@@ -637,7 +637,7 @@ fn row(label: &str, value: impl IntoElement, action: Option<Stateful<Div>>, t: &
         .items_center()
         .gap(px(16.))
         .py(px(12.))
-        .child(div().w(px(150.)).flex_none().text_size(px(13.)).text_color(t.muted).child(label.to_string()))
+        .child(div().w(px(theme::ROW_LABEL)).flex_none().text_size(px(13.)).text_color(t.muted).child(label.to_string()))
         .child(div().flex_1().min_w_0().text_size(px(13.)).text_color(t.text).child(value))
         .children(action)
 }
@@ -687,7 +687,7 @@ fn megabytes(bytes: u64) -> String {
 impl Launcher {
     fn sidebar(&self, cx: &mut Context<Self>) -> Div {
         let t = self.theme;
-        const STEP: f32 = 32.;
+        const STEP: f32 = theme::CONTROL + 2.;
         let mut nav = div().relative().flex().flex_col().gap(px(2.));
         // The selection is one pill that slides to the chosen item.
         let (from, to) = (self.previous_page.index() as f32 * STEP, self.page.index() as f32 * STEP);
@@ -696,8 +696,8 @@ impl Launcher {
                 .absolute()
                 .left_0()
                 .w_full()
-                .h(px(30.))
-                .rounded(px(6.))
+                .h(px(theme::CONTROL))
+                .rounded(px(theme::RADIUS))
                 .bg(t.raised)
                 .border_1()
                 .border_color(t.border)
@@ -715,12 +715,12 @@ impl Launcher {
                 .relative()
                 .flex()
                 .items_center()
-                .h(px(30.))
+                .h(px(theme::CONTROL))
                 .px(px(10.))
-                .rounded(px(6.))
+                .rounded(px(theme::RADIUS))
                 .text_size(px(theme::BODY))
                 .cursor_pointer()
-                .when(!active, |d| d.child(hover_layer(&id, t.hover.opacity(0.7), 6.)))
+                .when(!active, |d| d.child(hover_layer(&id, t.hover.opacity(0.7), theme::RADIUS)))
                 .child(
                     div()
                         .relative()
@@ -756,7 +756,7 @@ impl Launcher {
             .flex()
             .flex_col()
             .flex_none()
-            .w(px(200.))
+            .w(px(theme::SIDEBAR))
             .h_full()
             .bg(t.sidebar.opacity(0.8))
             .border_r_1()
@@ -785,9 +785,9 @@ impl Launcher {
                 .id(label)
                 .flex()
                 .items_center()
-                .h(px(26.))
+                .h(px(theme::SEGMENT))
                 .px(px(14.))
-                .rounded(px(5.))
+                .rounded(px(theme::RADIUS_SEGMENT))
                 .text_size(px(13.))
                 .cursor_pointer()
                 .when(active, |d| {
@@ -804,7 +804,7 @@ impl Launcher {
             .flex()
             .p(px(2.))
             .gap(px(2.))
-            .rounded(px(7.))
+            .rounded(px(theme::RADIUS_GROUP))
             .bg(t.raised)
             .border_1()
             .border_color(t.border)
@@ -1769,11 +1769,11 @@ fn main() {
     Application::new().run(|cx: &mut App| {
         cx.text_system()
             .add_fonts(vec![
-                Cow::Borrowed(include_bytes!("../assets/fonts/Geist-Regular.ttf").as_slice()),
-                Cow::Borrowed(include_bytes!("../assets/fonts/Geist-Medium.ttf").as_slice()),
-                Cow::Borrowed(include_bytes!("../assets/fonts/Geist-SemiBold.ttf").as_slice()),
-                Cow::Borrowed(include_bytes!("../assets/fonts/GeistMono-Regular.ttf").as_slice()),
-                Cow::Borrowed(include_bytes!("../assets/fonts/InstrumentSerif-Regular.ttf").as_slice()),
+                Cow::Borrowed(horizon_theme::fonts::GEIST_REGULAR),
+                Cow::Borrowed(horizon_theme::fonts::GEIST_MEDIUM),
+                Cow::Borrowed(horizon_theme::fonts::GEIST_SEMIBOLD),
+                Cow::Borrowed(horizon_theme::fonts::GEIST_MONO),
+                Cow::Borrowed(horizon_theme::fonts::INSTRUMENT_SERIF),
             ])
             .expect("bundled fonts");
         let bounds = Bounds::centered(None, size(px(1040.), px(700.)), cx);

launcher/src/theme.rs

@@ -1,22 +1,29 @@
-//! One neutral palette in two appearances and one accent. Spacing follows 4/8/12/16/24/32.
-//! Type: Geist for the interface, Instrument Serif for titles, Geist Mono for consoles and
-//! commands, all bundled (SIL Open Font License). Five sizes: 12, 13, 15, 28 and 56.
+//! The launcher's view of Horizon's design tokens (`crates/horizon-theme`), which the game's
+//! menus share: one neutral palette in two appearances and one accent, spacing 4/8/12/16/24/32,
+//! Geist / Instrument Serif / Geist Mono (bundled, SIL Open Font License), five sizes.
 use gpui::{rgb, Hsla, WindowAppearance};
+use horizon_theme as tokens;
 use std::time::Duration;
 
-pub const FONT: &str = "Geist";
-pub const DISPLAY: &str = "Instrument Serif";
-pub const MONO: &str = "Geist Mono";
+pub const FONT: &str = tokens::FONT;
+pub const DISPLAY: &str = tokens::DISPLAY;
+pub const MONO: &str = tokens::MONO;
 
-pub const SMALL: f32 = 12.;
-pub const BODY: f32 = 13.;
-pub const LARGE: f32 = 15.;
-pub const TITLE: f32 = 28.;
-pub const HERO: f32 = 56.;
+pub const SMALL: f32 = tokens::SMALL;
+pub const BODY: f32 = tokens::BODY;
+pub const LARGE: f32 = tokens::LARGE;
+pub const TITLE: f32 = tokens::TITLE;
+pub const HERO: f32 = tokens::HERO;
+
+/// Shapes and controls, shared with the game's menus.
+pub use tokens::{
+    CONTROL, CONTROL_LARGE, DISABLED, PRESSED, PRESSED_SOFT, PRIMARY_HOVER, RADIUS, RADIUS_CARD, RADIUS_GROUP,
+    RADIUS_SEGMENT, ROW_LABEL, SEGMENT, SIDEBAR,
+};
 
 /// Motion: short and eased out, never bouncy.
-pub const QUICK: Duration = Duration::from_millis(160);
-pub const MOVE: Duration = Duration::from_millis(240);
+pub const QUICK: Duration = tokens::QUICK;
+pub const MOVE: Duration = tokens::MOVE;
 
 #[derive(Clone, Copy)]
 pub struct Theme {
@@ -47,36 +54,27 @@ impl Theme {
     }
 
     pub fn dark() -> Self {
-        Self {
-            bg: c(0x111113),
-            sidebar: c(0x0c0c0d),
-            raised: c(0x1a1a1d),
-            hover: c(0x202024),
-            border: c(0x26262a),
-            text: c(0xe8e8ea),
-            muted: c(0x9a9aa1),
-            faint: c(0x626269),
-            accent: c(0x7c5cc4),
-            on_accent: c(0xffffff),
-            danger: c(0xd9705f),
-            dark: true,
-        }
+        Self::from(tokens::DARK)
     }
 
     pub fn light() -> Self {
+        Self::from(tokens::LIGHT)
+    }
+
+    fn from(p: tokens::Palette) -> Self {
         Self {
-            bg: c(0xfcfcfb),
-            sidebar: c(0xf4f4f2),
-            raised: c(0xf2f2f0),
-            hover: c(0xebebe8),
-            border: c(0xe3e3df),
-            text: c(0x19191b),
-            muted: c(0x63636a),
-            faint: c(0x9a9a9f),
-            accent: c(0x6a4bb3),
-            on_accent: c(0xffffff),
-            danger: c(0xb84a3a),
-            dark: false,
+            bg: c(p.bg),
+            sidebar: c(p.sidebar),
+            raised: c(p.raised),
+            hover: c(p.hover),
+            border: c(p.border),
+            text: c(p.text),
+            muted: c(p.muted),
+            faint: c(p.faint),
+            accent: c(p.accent),
+            on_accent: c(p.on_accent),
+            danger: c(p.danger),
+            dark: p.dark,
         }
     }
 }