Fortress Rollback Godot

A GDScript-only port of fortress-rollback — a fortified, deterministic, GGPO-inspired rollback networking library — targeting Godot 4.x.

[!WARNING] This project is in an early development phase. Local sync-test sessions and an external-input rollback core are implemented. Fixed-membership byte sessions include bounded input exchange and rollback. Optional SignalFish binary relay and direct WebRTC byte delivery are implemented. Browser release validation remains planned.

AI-Assisted Development Notice

This repository is developed with heavy AI-assistance and carries a generic agentic harness (inspired by unity-helpers):

• Every agent front-end (Claude Code, Codex, Copilot, OpenCode, Cursor, Gemini CLI, Windsurf, Cline, …) reads a thin pointer file that delegates to a single canonical context document.
• The canonical context and all skills live under .llm/.
• Skills follow the open Agent Skills SKILL.md standard, with generated discovery stubs under .claude/skills/ and .agents/skills/.
• Every file in the harness is capped at 300 lines (hard limit), enforced by tests, git hooks, and CI.

See .llm/context.md for the full operating manual. GitHub operations use authenticated MCP first and authenticated gh CLI for capability gaps.

Quick Start

Run the offline example with Godot 4.3 or newer:

godot --path . res://examples/offline/offline.tscn

Move the two players with WASD and the arrow keys. The example uses the shipped driver and complete integer snapshots while sync-test repeatedly rewinds gameplay.

Run the packet-loss example with two independent byte sessions:

godot --path . res://examples/peer/peer.tscn

Move players with WASD and the arrow keys. Toggle packet loss, reordering or a partition to observe prediction stalls and recovery. Delivery runs in process.

Try the delayed spectator example to watch a corrected host stream while the host keeps playing. Press P to pause and catch up the viewer. Delivery runs in process; live spectator networking remains planned.

For matches that continue after peer loss, enable the graceful coordinated drop policy. The guide separates supported behavior from the remaining physical-departure and upstream-parity gates. Hot join and session reactivation remain unavailable; see supported features.

For an addon-only install, build and verify a candidate archive.

The supported features page states the supported Godot