ios

libs/scrap/src/ios/README.md

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+# iOS Screen Capture Implementation
+
+This implementation provides screen capture functionality for iOS using ReplayKit framework through Rust FFI.
+
+## Architecture
+
+### Components
+
+1. **Native Layer** (`native/ScreenCapture.m`)
+   - Implements ReplayKit screen recording for in-app capture
+   - Handles message port communication for system-wide capture
+   - Converts pixel formats (BGRA to RGBA)
+   - Provides C interface for Rust FFI
+
+2. **FFI Layer** (`ffi.rs`)
+   - Rust bindings to native C functions
+   - Frame buffer management
+   - Callback mechanism for frame updates
+
+3. **Rust Interface** (`mod.rs`)
+   - Implements `TraitCapturer` for compatibility with RustDesk
+   - Frame management and duplicate detection
+   - Display information handling
+
+4. **Broadcast Extension** (`flutter/ios/BroadcastExtension/`)
+   - Separate app extension for system-wide screen capture
+   - Uses message ports to send frames to main app
+   - Required for capturing content outside the app
+
+## Features
+
+### In-App Capture
+- Uses `RPScreenRecorder` API
+- Captures only RustDesk app content
+- No additional permissions required beyond initial prompt
+
+### System-Wide Capture
+- Uses Broadcast Upload Extension
+- Can capture entire screen including other apps
+- Requires user to explicitly start from Control Center
+- Communicates via CFMessagePort
+
+## Usage
+
+```rust
+// Initialize and start capture
+let display = Display::primary()?;
+let mut capturer = Capturer::new(display)?;
+
+// Get frames
+match capturer.frame(Duration::from_millis(33)) {
+    Ok(frame) => {
+        // Process frame
+    }
+    Err(e) if e.kind() == io::ErrorKind::WouldBlock => {
+        // No new frame available
+    }
+    Err(e) => {
+        // Handle error
+    }
+}
+
+// For system-wide capture
+ffi::show_broadcast_picker();
+```
+
+## Setup Requirements
+
+1. **Xcode Configuration**
+   - Add Broadcast Upload Extension target
+   - Configure app groups (if using shared container)
+   - Set up proper code signing
+
+2. **Info.plist**
+   - Add microphone usage description (for audio capture)
+   - Configure broadcast extension settings
+
+3. **Build Settings**
+   - Link ReplayKit framework
+   - Enable Objective-C ARC
+   - Set minimum iOS version to 11.0 (12.0 for broadcast picker)
+
+## Limitations
+
+- Screen recording requires iOS 11.0+
+- System-wide capture requires iOS 12.0+
+- User must grant permission for screen recording
+- Performance depends on device capabilities
+- Broadcast extension has memory limits (~50MB)
+
+## Security Considerations
+
+- Screen recording is a sensitive permission
+- iOS shows recording indicator when active
+- Broadcast extension runs in separate process
+- Message port communication is local only