Feat/UI scale

CHANGELOG.md

@@ -7,8 +7,28 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Changed
+
+- **The UI fits itself to the screen it is on.** Every screen is laid out in
+  points against a 640×480 design, and one zoom factor carries the lot — fonts,
+  rows, gaps — so a desktop window and a 752×560 Flip panel show the same layout
+  at the size each has room for, rather than the design at 1:1 pixels and text
+  that shrinks with the panel. A panel only a little past the design keeps a
+  whole zoom: fractional zoom lands glyphs between pixels, which reads as uneven
+  type where there is no subpixel positioning, so the spare pixels become margin
+  instead. A phone held upright is the same screen turned, so the fit measures
+  long edge to long edge and the lists get a narrower measure, not smaller rows.
+- **`RETSEND_SCALE` now pins the base** the setting is read over, instead of
+  being the whole answer. Android no longer passes the display density — the fit
+  lands on the same physical size at any density.
+
 ### Added
 
+- **A "UI scale" setting**, 60% to 160% of what the screen itself asks for,
+  stepped with ◂ ▸ on its row (L1/R1 still switch tabs, and the hints name both
+  arrows so a screen with no pad can reach them). Persisted as
+  `[display] scale`, applied live.
+
 - **A send can be repeated from the History tab**, with A on its row. The log
   now keeps the source paths of a send and the address it went to; the resend
   dials the peer under that alias as the radar has it *now*, so a device that

Cargo.toml

@@ -52,10 +52,12 @@ ureq = { version = "3", default-features = false, features = ["rustls"] }
 # Patch floor, not a pin: bare "0.23" also admits 0.23.13..=0.23.17, which panic
 # in Acceptor::accept (RUSTSEC-2024-0399, fixed in 0.23.18).
 rustls = { version = "0.23.42", default-features = false, features = ["ring", "std"] }
-rcgen = "0.14"
+# Default features are off only to drop rcgen's `pem`: we read its DER output,
+# and that feature pins pem 3, duplicating the crate against our own.
+rcgen = { version = "0.14", default-features = false, features = ["ring"] }
 # Only to hand ureq the stored identity: its client-auth types parse PEM, and
 # the DER constructor's `KeyKind` is not exported.
-pem = "3"
+pem = "4"
 sha2 = "0.11"
 # Only for SO_REUSEADDR/SO_REUSEPORT before binding UDP 53317 — std can't set
 # them pre-bind, and without them we can't coexist with the official LocalSend

README.md

@@ -16,7 +16,7 @@
 client for retro handhelds: send and receive files with your phone
 or PC over Wi-Fi, no cable or SSH. Compatible with the official LocalSend apps.
 
-It targets [PortMaster-compatible](https://portmaster.games/supported-devices.html) Linux handhelds and the Miyoo Mini Plus and Flip running OnionOS or Allium, all of which are gamepad-only systems without a compositor. It also runs on regular desktop Linux and on Android handhelds and phones too.
+It targets [PortMaster-compatible](https://portmaster.games/supported-devices.html) Linux handhelds and the Miyoo Mini Plus and Flip running [OnionOS](https://github.com/OnionUI/Onion), [spruceOS](https://github.com/spruceUI/spruceOS) or [Allium](https://github.com/goweiwen/Allium), all of which are gamepad-only systems without a compositor. It also runs on regular desktop Linux and on Android.
 
 <p align="center">
   <img src="resources/retsend-devices.jpg" alt="Three devices on a couch: a handheld showing the radar of nearby devices, a clamshell handheld waiting to receive, and a phone running the official LocalSend app" width="480">
@@ -128,7 +128,7 @@ hint along the bottom to press the button it names.
 
 | Pad          | Keyboard   | Action                                        |
 |--------------|------------|-----------------------------------------------|
-| D-pad / stick| Arrows     | Navigate · left/right switch tabs             |
+| D-pad / stick| Arrows     | Navigate · left/right switch tabs, or step a settings value |
 | A            | Enter      | Send to device · select file · accept · repeat a send · type |
 | B            | Esc        | Back · decline · cancel · leave the keyboard  |
 | X            | X / Bksp   | Add a device by IP · pick where an incoming transfer lands · delete a history row · erase a character · take every file in the folder |
@@ -147,10 +147,13 @@ Settings screen edits everything in it except:
 - `[transfer] browser_roots` — extra mount points for the file browser
 - `[transfer] history_limit` — max transfers kept in the History tab (default 200)
 - `[transfer] pinned_paths`, `last_send_dir` — written by Y and by sending
+- `[display] scale` — UI size over what the screen itself asks for (0.6–1.6,
+  the "UI scale" setting; every screen is drawn for 640×480 and fitted from there)
 
 Environment variables override paths and control logging at launch:
 `RETSEND_DATA_DIR`, `RETSEND_CONFIG`, `RETSEND_SAVE_DIR`, `RETSEND_BROWSER_ROOTS`
-(`:`-separated), `RETSEND_ALIAS`, `RETSEND_SCALE`, `RETSEND_GLES=0|1`,
+(`:`-separated), `RETSEND_ALIAS`, `RETSEND_SCALE` (pins the base the `[display]
+scale` setting is read over, replacing the fit), `RETSEND_GLES=0|1`,
 `RETSEND_SOFTWARE=1`, `RETSEND_BLIT=1`, `RETSEND_KEYMAP=miyoo|desktop`,
 `RETSEND_LOG_LEVEL`, `RETSEND_LOG_FILE`, `RETSEND_PANIC_FILE`.
 

android/README.md

@@ -65,7 +65,8 @@ Logs go to logcat: `adb logcat -s retsend`.
   PortMaster and OnionOS launchers set, before SDL starts: `RETSEND_DATA_DIR`
   (internal `getFilesDir()`: config, TLS identity, history), `RETSEND_SAVE_DIR`,
   `RETSEND_BROWSER_ROOTS` (the storage volumes it can reach), `RETSEND_ALIAS`
-  (`Build.MODEL`), `RETSEND_SCALE` (display density) and `RETSEND_PANIC_FILE`.
+  (`Build.MODEL`) and `RETSEND_PANIC_FILE`. Not the scale: fitting the 640×480
+  design to the panel already lands on the same physical size at any density.
 - **Permissions** — `RetsendLauncherActivity` is the launcher entry and asks for
   all-files access *before* starting SDL, because the paths above are read once
   at startup and the save folder is persisted on first run.

android/app/src/main/java/com/retsend/RetsendActivity.java

@@ -42,9 +42,8 @@ protected void onCreate(Bundle savedInstanceState) {
         setEnv("RETSEND_BROWSER_ROOTS", browserRoots());
         // Only seeds the alias; the Settings screen owns it from then on.
         setEnv("RETSEND_ALIAS", Build.MODEL);
-        // Phone screens are dense enough that the UI would be unreadable at 1:1
-        // pixels. ~1.0 (mdpi) .. ~3.5 (xxxhdpi), applied to egui's zoom factor.
-        setEnv("RETSEND_SCALE", String.valueOf(getResources().getDisplayMetrics().density));
+        // Not RETSEND_SCALE: fitting the 640x480 design to the panel already
+        // lands on the same physical size whatever the density is.
 
         acquireMulticastLock();
 

src/app/mod.rs

@@ -393,8 +393,13 @@ impl App {
 
     /// Nav on a tab: left/right step between tabs the same way L1/R1 do, and
     /// up/down move the active tab's cursor (Receive has nothing to move).
+    /// The exception is a settings row carrying a value — there left/right walk
+    /// the value, and L1/R1 remain the way off the tab.
     fn tab_nav(&mut self, dir: Direction) {
         match dir {
+            Direction::Left | Direction::Right if self.on_stepper_row() => {
+                self.step_scale(if dir == Direction::Left { -1 } else { 1 });
+            }
             Direction::Left => self.switch_tab(-1),
             Direction::Right => self.switch_tab(1),
             Direction::Up | Direction::Down => match self.ui.tabs.active() {
@@ -483,6 +488,19 @@ impl App {
             .or_else(|| (!entry.peer_base.is_empty()).then(|| entry.peer_base.clone()))
     }
 
+    /// Is the cursor on a settings row whose value left/right walk?
+    fn on_stepper_row(&self) -> bool {
+        self.ui.tabs.active() == Tab::Settings && self.ui.settings.row().is_stepper()
+    }
+
+    /// ◂ ▸ on the scale row: nudge the factor over the panel's own fit. The
+    /// zoom follows on the next frame; the config is written on leaving the tab,
+    /// like every other setting here.
+    fn step_scale(&mut self, dir: i32) {
+        let scale = &mut self.config.display.scale;
+        *scale = crate::config::display::SCALE.step(*scale, dir);
+    }
+
     /// A on a settings row: open its editor or toggle it.
     fn edit_setting(&mut self) {
         match self.ui.settings.row() {
@@ -510,6 +528,8 @@ impl App {
                 self.ui.routes.open(auto);
             }
             SettingsRow::About => self.ui.about.open(),
+            // Walked with ◂ ▸; A on it would have to pick a direction.
+            SettingsRow::Scale => {}
             SettingsRow::Port => {
                 self.ui
                     .osk

src/config/display.rs

@@ -1,5 +1,15 @@
+use super::Range;
 use serde::{Deserialize, Serialize};
 
+/// How far the scale may be pushed either side of the fit. Relative, not
+/// absolute: the app already sizes itself to the panel, and a factor that suits
+/// a handheld would be wrong on a desktop.
+pub const SCALE: Range = Range {
+    min: 0.6,
+    max: 1.6,
+    step: 0.05,
+};
+
 /// Window/display settings (`[display]` in the config).
 #[derive(Clone, Serialize, Deserialize)]
 #[serde(default)]
@@ -9,6 +19,9 @@ pub struct DisplayConfig {
     /// Request an OpenGL ES context (required on Mali handhelds) instead of
     /// desktop GL. Can be overridden at startup via `RETSEND_GLES=0`.
     pub use_gles: bool,
+    /// Over the scale the panel's own size asks for, so one setting means the
+    /// same thing on every device.
+    pub scale: f32,
 }
 
 impl Default for DisplayConfig {
@@ -17,6 +30,7 @@ impl Default for DisplayConfig {
             width: 640,
             height: 480,
             use_gles: true,
+            scale: 1.0,
         }
     }
 }

src/config/mod.rs

@@ -9,7 +9,7 @@
 use serde::{Deserialize, Serialize};
 
 mod device;
-mod display;
+pub mod display;
 mod input;
 mod network;
 mod paths;
@@ -23,6 +23,23 @@ pub use network::NetworkConfig;
 pub use paths::{data_dir, device_scale, env_browser_roots};
 pub use transfer::TransferConfig;
 
+/// A settings value the UI walks in steps rather than types.
+pub struct Range {
+    pub min: f32,
+    pub max: f32,
+    pub step: f32,
+}
+
+impl Range {
+    /// Step `value` by `dir` steps and clamp it. Snapped back onto the grid:
+    /// adding a step over and over drifts, and the drift is what the config
+    /// file ends up carrying.
+    pub fn step(&self, value: f32, dir: i32) -> f32 {
+        let stepped = value + dir as f32 * self.step;
+        ((stepped / self.step).round() * self.step).clamp(self.min, self.max)
+    }
+}
+
 #[derive(Clone, Default, Serialize, Deserialize)]
 #[serde(default)]
 pub struct AppConfig {
@@ -77,6 +94,12 @@ impl AppConfig {
     fn sanitize(&mut self) {
         fix("display.width", &mut self.display.width, 320, 7680);
         fix("display.height", &mut self.display.height, 240, 4320);
+        fix_f32(
+            "display.scale",
+            &mut self.display.scale,
+            display::SCALE.min,
+            display::SCALE.max,
+        );
         // Ports below 1024 need root; 0 means "ephemeral" which would break
         // re-announce consistency.
         fix("network.port", &mut self.network.port, 1024, u16::MAX);

src/config/paths.rs

@@ -1,15 +1,14 @@
 //! Path/directory and environment resolution shared across the crate.
 
-/// UI scale factor. The handheld launcher can set `RETSEND_SCALE` for tiny or
-/// high-DPI screens; desktop leaves it unset and stays at 1.0. Applied to
-/// egui's zoom factor. Clamped to a sane range.
-pub fn device_scale() -> f32 {
+/// UI scale override from `RETSEND_SCALE`, clamped. `None` — the usual case —
+/// leaves the panel to decide; a launcher that knows better says so here, and
+/// the `display.scale` setting is still read over it.
+pub fn device_scale() -> Option<f32> {
     std::env::var("RETSEND_SCALE")
         .ok()
         .and_then(|v| v.parse::<f32>().ok())
         .filter(|s| s.is_finite() && *s > 0.0)
         .map(|s| s.clamp(0.5, 6.0))
-        .unwrap_or(1.0)
 }
 
 /// The per-user data directory (with a trailing separator) for writable files —

src/overlay/settings.rs

@@ -12,12 +12,21 @@ pub enum SettingsRow {
     AutoRoutes,
     Routes,
     Port,
+    Scale,
     About,
 }
 
+impl SettingsRow {
+    /// Rows whose value ◂ ▸ walk instead of switching tabs.
+    pub fn is_stepper(self) -> bool {
+        self == SettingsRow::Scale
+    }
+}
+
 /// Top-to-bottom order on screen; `crate::ui::settings` labels them in the same
-/// order, one cursor indexes both. Port is late — it is set once, if ever.
-const ROWS: [SettingsRow; 9] = [
+/// order, one cursor indexes both. Port and the scale are late — both are set
+/// once, if ever.
+const ROWS: [SettingsRow; 10] = [
     SettingsRow::Alias,
     SettingsRow::SaveDir,
     SettingsRow::QuickSave,
@@ -26,6 +35,7 @@ const ROWS: [SettingsRow; 9] = [
     SettingsRow::AutoRoutes,
     SettingsRow::Routes,
     SettingsRow::Port,
+    SettingsRow::Scale,
     SettingsRow::About,
 ];