Screensharing #10
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Add xdg-desktop-portal-screencomposer component implementing the org.freedesktop.impl.portal.ScreenCast D-Bus interface. Features: - ScreenCast portal backend for PipeWire screen sharing - Monitor (output) capture support - Cursor modes: Hidden, Embedded, Metadata - Session and stream lifecycle management The portal acts as a bridge between the standard XDG Desktop Portal interface and ScreenComposer's internal D-Bus API, enabling applications like Chromium, Firefox, and OBS to share screens. Not yet implemented: - Window capture - Restore tokens (session persistence) - Permission dialogs (currently auto-grants)
Phase 1 of screenshare implementation - wiring up the compositor side: - Add ScreencastSession and ActiveStream structs for session state - Add screenshare_sessions HashMap to ScreenComposer state - Implement command handlers in handle_screenshare_command(): - CreateSession: creates session in compositor state - StartRecording: creates PipeWireStream + ScreencastSessionTap, registers tap - StopRecording: unregisters tap, removes stream - DestroySession: cleans up all streams in session - Wire frame capture into render loops: - winit: RGBA capture inside render closure after render_output() - udev: RGBA capture via capture_rgba_frame() after render_frame() - Call notify_rgba_with_damage() with captured frames and damage regions The PipeWire stream is still a skeleton - frames flow through the pipeline but are not yet sent to actual PipeWire. Next step is real PipeWire integration. 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
Add zbus 4 and pipewire 0.9 dependencies for the screenshare D-Bus service and PipeWire stream implementation. Also clean up compiler warnings with #[allow] attributes for fields/functions that will be used in the PipeWire implementation. 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
The original design doc has been superseded by screenshare-plan.md which contains the updated implementation plan with handover notes. 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
Replace the placeholder PipeWire implementation with a working one: - Create dedicated PipeWire thread with MainLoopBox, ContextBox - Stream connects as video source with proper properties - Video format negotiation (BGRA/RGBA/BGRx/RGBx) - SHM buffer handling with automatic allocation (ALLOC_BUFFERS) - Thread-safe synchronization via atomics and mpsc channels - FD export for portal clients via loop_fd() - Proper cleanup on stop/drop The stream receives RGBA frames from the compositor's render loop via ScreencastSessionTap and queues them to PipeWire buffers. 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
- Add docs/screenshare.md with full architecture, D-Bus API reference, and component descriptions for the screen sharing implementation - Update docs/xdg-desktop-portal.md with reference to screenshare.md and current feature status - Update docs/project-structure.md to include screenshare module - Update AGENTS.md/CLAUDE.md to reflect completed implementation 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
Minimal example demonstrating DRIVER mode with ALLOC_BUFFERS: - Self-allocated memfd buffers - Timer-based frame triggering - Animated test pattern output 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
- Add PendingFrame enum to handle both RGBA and DMA-BUF frame types - Update PipeWireThreadState with dmabuf_map for zero-copy path - Update frame reception to accept both RGBA (winit) and DMA-BUF (udev) Winit SHM screenshare still working, DMA-BUF implementation in progress
Introduces infrastructure to support both SHM (CPU copy) and DMA-BUF (zero-copy) frame paths in PipeWire stream: - Added PendingFrame enum: Rgba (SHM) | DmaBuf (zero-copy) - Updated both process callbacks to match on PendingFrame type - Frame reception wraps FrameData into PendingFrame before storage - Added dmabuf_map field to track DMA-BUF FD mappings RGBA/SHM path fully functional on winit backend. DMA-BUF path stubbed with TODOs for future implementation on udev backend.
Updated the file header and description for clarity.
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Pull request overview
This PR implements comprehensive screensharing functionality for ScreenComposer via PipeWire and xdg-desktop-portal integration. The implementation adds a D-Bus service on the compositor side, a separate portal backend component, and frame capture infrastructure integrated into the render loops.
Key Changes:
- Complete PipeWire-based screensharing pipeline with D-Bus API
- Frame tap manager for capturing rendered frames with damage tracking
- XDG Desktop Portal backend component for standard portal API compatibility
- Integration into winit and udev render loops
Reviewed changes
Copilot reviewed 36 out of 37 changed files in this pull request and generated no comments.
Show a summary per file
| File | Description |
|---|---|
src/screenshare/mod.rs |
Session state management and compositor command handlers |
src/screenshare/frame_tap.rs |
Frame tap infrastructure with damage tracking support |
src/screenshare/pipewire_stream.rs |
PipeWire stream management with SHM buffer handling |
src/screenshare/dbus_service.rs |
D-Bus service implementation for compositor API |
src/screenshare/session_tap.rs |
Per-session frame filtering and distribution |
src/state/mod.rs |
Added frame tap manager and screenshare session tracking |
src/winit.rs |
RGBA frame capture integration in render loop |
src/udev.rs |
RGBA frame capture integration in render loop |
src/lib.rs |
Module export for screenshare |
components/xdg-desktop-portal-sc/ |
Complete portal backend implementation |
sample-clients/pipewire-video-source/ |
Example PipeWire video source |
docs/screenshare.md |
Comprehensive architecture documentation |
docs/xdg-desktop-portal.md |
Portal integration documentation |
Cargo.toml |
Dependency additions (zbus, pipewire, memfd, memmap2) |
Due to the comprehensive nature of this PR and reaching iteration limits, I've focused on identifying the most critical issues. The implementation is well-structured overall with good separation of concerns between the compositor-side screensharing, D-Bus service, and portal backend.
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Removed quick test and debugging sections from README.md
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