feat: add desktop teleprompter

apps/desktop/src-tauri/src/general_settings.rs

@@ -110,6 +110,7 @@ const DEFAULT_EXCLUDED_WINDOW_TITLES: &[&str] = &[
     "Cap Capture Area",
     "Cap Mode Selection",
     "Cap Recordings Overlay",
+    "Cap Teleprompter",
 ];
 
 pub fn default_excluded_windows() -> Vec<WindowExclusion> {

apps/desktop/src-tauri/src/lib.rs

@@ -4911,6 +4911,8 @@ pub async fn run(recording_logging_handle: LoggingHandle, logs_dir: PathBuf) {
             clip_thumbnails::get_clip_thumbnail,
             windows::position_traffic_lights,
             windows::set_theme,
+            windows::set_teleprompter_window_level,
+            windows::set_teleprompter_window_opacity,
             windows::apply_macos_liquid_glass_background,
             global_message_dialog,
             show_window,

apps/desktop/src-tauri/src/platform/macos/mod.rs

@@ -26,6 +26,21 @@ pub fn set_window_level(window: tauri::Window, level: objc2_app_kit::NSWindowLev
     });
 }
 
+pub fn set_window_opacity(window: tauri::Window, opacity: f64) {
+    let opacity = opacity.clamp(0.45, 1.0);
+    let c_window = window.clone();
+    _ = window.run_on_main_thread(move || unsafe {
+        use cocoa::base::id;
+        use objc::{msg_send, sel, sel_impl};
+
+        let Ok(ns_win) = c_window.ns_window() else {
+            return;
+        };
+        let ns_win = ns_win as id;
+        let _: () = msg_send![ns_win, setAlphaValue: opacity];
+    });
+}
+
 pub fn apply_squircle_corners(window: &tauri::WebviewWindow, radius: f64) {
     use cocoa::base::{id, nil};
     use cocoa::foundation::NSString;

apps/desktop/src-tauri/src/recording.rs

@@ -57,6 +57,8 @@ use crate::camera::{CameraPreviewManager, CameraPreviewShape};
 use crate::general_settings;
 use crate::permissions;
 use crate::web_api::AuthedApiError;
+#[cfg(target_os = "macos")]
+use crate::window_exclusion::WindowExclusion;
 use crate::{
     App, CameraWindowOperationLock, CurrentRecordingChanged, EditorRecordingAdded,
     FinalizingRecordings, MutableState, NewStudioRecordingAdded, RecordingStarted, RecordingState,
@@ -1866,6 +1868,16 @@ pub async fn start_recording(
                     window_exclusions
                 };
 
+                let teleprompter_exclusion = WindowExclusion {
+                    bundle_identifier: None,
+                    owner_name: None,
+                    window_title: Some(CapWindowId::Teleprompter.title()),
+                };
+                let mut window_exclusions = window_exclusions;
+                if !window_exclusions.contains(&teleprompter_exclusion) {
+                    window_exclusions.push(teleprompter_exclusion);
+                }
+
                 let mut excluded_window_ids =
                     crate::window_exclusion::resolve_window_ids(&window_exclusions);
                 crate::window_exclusion::append_matching_webview_window_ids(

apps/desktop/src-tauri/src/windows.rs

@@ -45,6 +45,12 @@ use cap_recording::{feeds, sources::screen_capture::ScreenCaptureTarget};
 #[cfg(target_os = "macos")]
 const DEFAULT_TRAFFIC_LIGHTS_INSET: LogicalPosition<f64> = LogicalPosition::new(12.0, 12.0);
 
+#[cfg(target_os = "macos")]
+const MAIN_PANEL_LEVEL: i32 = 100;
+
+#[cfg(target_os = "macos")]
+const TELEPROMPTER_PANEL_LEVEL: objc2_app_kit::NSWindowLevel = MAIN_PANEL_LEVEL as isize + 1;
+
 const DEFAULT_FALLBACK_DISPLAY_WIDTH: f64 = 1920.0;
 const DEFAULT_FALLBACK_DISPLAY_HEIGHT: f64 = 1080.0;
 
@@ -937,6 +943,7 @@ pub enum CapWindowId {
     Debug,
     ScreenshotEditor { id: u32 },
     Onboarding,
+    Teleprompter,
 }
 
 impl FromStr for CapWindowId {
@@ -955,6 +962,7 @@ impl FromStr for CapWindowId {
             "mode-select" => Self::ModeSelect,
             "debug" => Self::Debug,
             "onboarding" => Self::Onboarding,
+            "teleprompter" => Self::Teleprompter,
             s if s.starts_with("editor-") => Self::Editor {
                 id: s
                     .replace("editor-", "")
@@ -1005,6 +1013,7 @@ impl std::fmt::Display for CapWindowId {
             Self::Debug => write!(f, "debug"),
             Self::ScreenshotEditor { id } => write!(f, "screenshot-editor-{id}"),
             Self::Onboarding => write!(f, "onboarding"),
+            Self::Teleprompter => write!(f, "teleprompter"),
         }
     }
 }
@@ -1027,6 +1036,7 @@ impl CapWindowId {
             Self::Camera => "Cap Camera".to_string(),
             Self::RecordingsOverlay => "Cap Recordings Overlay".to_string(),
             Self::TargetSelectOverlay { .. } => "Cap Target Select".to_string(),
+            Self::Teleprompter => "Cap Teleprompter".to_string(),
             _ => "Cap".to_string(),
         }
     }
@@ -1087,6 +1097,7 @@ impl CapWindowId {
             | Self::RecordingControls
             | Self::TargetSelectOverlay { .. } => None,
             Self::Settings => Some(Some(LogicalPosition::new(22.0, 22.0))),
+            Self::Teleprompter => Some(Some(LogicalPosition::new(14.0, 14.0))),
             _ => Some(None),
         }
     }
@@ -1620,8 +1631,6 @@ impl ShowCapWindow {
                             use tauri_nspanel::panel_delegate;
                             use crate::panel_manager::try_to_panel;
 
-                            const MAIN_PANEL_LEVEL: i32 = 100;
-
                             let delegate = panel_delegate!(MainPanelDelegate {
                                 window_did_become_key,
                                 window_did_resign_key
@@ -3233,6 +3242,38 @@ pub fn position_traffic_lights(_window: tauri::Window, _controls_inset: Option<(
     );
 }
 
+#[tauri::command]
+#[specta::specta]
+#[instrument(skip(_window))]
+pub fn set_teleprompter_window_level(_window: tauri::Window, _always_on_top: bool) {
+    #[cfg(target_os = "macos")]
+    if _window.label() == CapWindowId::Teleprompter.to_string() {
+        let level = if _always_on_top {
+            TELEPROMPTER_PANEL_LEVEL
+        } else {
+            objc2_app_kit::NSNormalWindowLevel
+        };
+        crate::platform::set_window_level(_window, level);
+    }
+
+    #[cfg(not(target_os = "macos"))]
+    if _window.label() == CapWindowId::Teleprompter.to_string()
+        && let Err(error) = _window.set_always_on_top(_always_on_top)
+    {
+        warn!(?error, "Failed to update teleprompter window level");
+    }
+}
+
+#[tauri::command]
+#[specta::specta]
+#[instrument(skip(_window))]
+pub fn set_teleprompter_window_opacity(_window: tauri::Window, _opacity: f64) {
+    #[cfg(target_os = "macos")]
+    if _window.label() == CapWindowId::Teleprompter.to_string() {
+        crate::platform::set_window_opacity(_window, _opacity);
+    }
+}
+
 #[cfg(target_os = "macos")]
 fn position_traffic_lights_impl(
     window: &tauri::Window,
@@ -3305,7 +3346,11 @@ fn content_protection_enabled(app: &AppHandle<Wry>) -> bool {
         .unwrap_or(false)
 }
 
-fn window_matches_exclusion_list(app: &AppHandle<Wry>, window_title: &str) -> bool {
+fn window_capture_excluded(app: &AppHandle<Wry>, window_title: &str) -> bool {
+    if window_title == CapWindowId::Teleprompter.title() {
+        return true;
+    }
+
     let matches = |list: &[WindowExclusion]| {
         list.iter()
             .any(|entry| entry.matches(None, None, Some(window_title)))
@@ -3321,7 +3366,7 @@ fn window_matches_exclusion_list(app: &AppHandle<Wry>, window_title: &str) -> bo
 fn should_protect_window(app: &AppHandle<Wry>, window_title: &str) -> bool {
     content_protection_enabled(app)
         && !capture_exclusion_hides_ui()
-        && window_matches_exclusion_list(app, window_title)
+        && window_capture_excluded(app, window_title)
 }
 
 pub fn apply_content_protection(app: &AppHandle<Wry>, enabled: bool) {
@@ -3343,7 +3388,7 @@ pub fn apply_content_protection(app: &AppHandle<Wry>, enabled: bool) {
         }
 
         let title = id.title();
-        let should_protect = enabled && window_matches_exclusion_list(app, &title);
+        let should_protect = enabled && window_capture_excluded(app, &title);
         let _ = window.set_content_protected(should_protect);
 
         #[cfg(target_os = "windows")]

apps/desktop/src/app.tsx

@@ -95,6 +95,7 @@ const TargetSelectOverlayPage = lazy(
 const WindowCaptureOccluderPage = lazy(
 	() => import("./routes/window-capture-occluder"),
 );
+const TeleprompterPage = lazy(() => import("./routes/teleprompter"));
 
 const queryClient = new QueryClient({
 	defaultOptions: {
@@ -248,6 +249,11 @@ function Inner() {
 						path="/window-capture-occluder"
 						component={WindowCaptureOccluderPage}
 					/>
+					<Route
+						path="/teleprompter"
+						info={{ AUTO_SHOW_WINDOW: false }}
+						component={TeleprompterPage}
+					/>
 				</Router>
 			</CapErrorBoundary>
 		</>

apps/desktop/src/routes/(window-chrome)/new-main/index.tsx

@@ -79,6 +79,7 @@ import {
 	type UpdateCheckResult,
 	type UploadProgress,
 } from "~/utils/tauri";
+import { openTeleprompter } from "~/utils/teleprompter";
 import IconCapLogoFull from "~icons/cap/logo-full";
 import IconCapLogoFullDark from "~icons/cap/logo-full-dark";
 import IconLucideAppWindowMac from "~icons/lucide/app-window-mac";
@@ -87,6 +88,7 @@ import IconLucideBug from "~icons/lucide/bug";
 import IconLucideCircleHelp from "~icons/lucide/circle-help";
 import IconLucideImage from "~icons/lucide/image";
 import IconLucideImport from "~icons/lucide/import";
+import IconLucideScanText from "~icons/lucide/scan-text";
 import IconLucideSearch from "~icons/lucide/search";
 import IconLucideSettings from "~icons/lucide/settings";
 import IconLucideSquarePlay from "~icons/lucide/square-play";
@@ -2779,6 +2781,16 @@ function Page() {
 								<IconLucideSquarePlay class="transition-colors text-gray-11 size-4 hover:text-gray-12" />
 							</button>
 						</Tooltip>
+						<Tooltip content={<span>Teleprompter</span>}>
+							<button
+								type="button"
+								onClick={() => void openTeleprompter()}
+								class="flex justify-center items-center size-5 focus:outline-hidden"
+								aria-label="Open teleprompter"
+							>
+								<IconLucideScanText class="transition-colors text-gray-11 size-4 hover:text-gray-12" />
+							</button>
+						</Tooltip>
 						<ChangelogButton />
 						{import.meta.env.DEV && (
 							<button

apps/desktop/src/routes/teleprompter-utils.test.ts

@@ -0,0 +1,33 @@
+import { describe, expect, it } from "vitest";
+import {
+	advancePlaybackPosition,
+	calculatePlaybackSpeed,
+	clamp,
+	countWords,
+} from "./teleprompter-utils";
+
+describe("teleprompter utilities", () => {
+	it("counts words in pasted scripts", () => {
+		expect(countWords("  One   two\nthree ")).toBe(3);
+		expect(countWords(" ")).toBe(0);
+	});
+
+	it("clamps a setting to its supported range", () => {
+		expect(clamp(5, 10, 20)).toBe(10);
+		expect(clamp(25, 10, 20)).toBe(20);
+	});
+
+	it("calculates a positive scroll speed from reading duration", () => {
+		expect(calculatePlaybackSpeed(600, 300, 150)).toBe(5);
+		expect(calculatePlaybackSpeed(-10, 300, 150)).toBe(0);
+	});
+
+	it("retains sub-pixel movement across animation frames", () => {
+		let position = 0;
+		for (let frame = 0; frame < 60; frame += 1) {
+			position = advancePlaybackPosition(position, 100, 10, 1 / 60);
+		}
+
+		expect(position).toBeCloseTo(10);
+	});
+});

apps/desktop/src/routes/teleprompter-utils.ts

@@ -0,0 +1,30 @@
+export function countWords(text: string) {
+	return text.trim() ? text.trim().split(/\s+/u).length : 0;
+}
+
+export function clamp(value: number, minimum: number, maximum: number) {
+	return Math.min(Math.max(value, minimum), maximum);
+}
+
+export function calculatePlaybackSpeed(
+	maximumScroll: number,
+	wordCount: number,
+	wordsPerMinute: number,
+) {
+	const durationSeconds =
+		(Math.max(1, wordCount) / Math.max(1, wordsPerMinute)) * 60;
+	return Math.max(0, maximumScroll) / Math.max(1, durationSeconds);
+}
+
+export function advancePlaybackPosition(
+	position: number,
+	maximumScroll: number,
+	pixelsPerSecond: number,
+	elapsedSeconds: number,
+) {
+	return Math.min(
+		Math.max(0, maximumScroll),
+		Math.max(0, position) +
+			Math.max(0, pixelsPerSecond) * Math.max(0, elapsedSeconds),
+	);
+}