Iron Curtain — Design Documentation

Replay Analysis, Sharing & Tools

Parent page: Replays

Post-Game Summary Screen

Accessible from:

• Post-Game → [Summary] (after a live match)
• Replay Viewer → [Summary] button (during or after replay playback)
• Replay Browser → right-click → [View Summary]

The summary screen does not require replaying the match — it reads from the analysis event stream embedded in the .icrep file.

┌──────────────────────────────────────────────────────────────────┐
│  MATCH SUMMARY — Coastal Fortress                     [← Back]   │
│                                                                  │
│  P1: You (Allied) — VICTORY     P2: PlayerX (Soviet) — DEFEAT   │
│  Duration: 12:34   Balance: IC Default   Speed: Normal           │
│                                                                  │
│  [Overview] [Economy] [Military] [Build Order] [Heatmaps]        │
│  ─────────────────────────────────────────────────────────────── │
│                                                                  │
│  OVERVIEW                                                        │
│  ┌────────────────────────────────────────────────────────────┐ │
│  │  Army Value Graph (over time)                              │ │
│  │  ┌─────────────────────────────────────────────────────┐  │ │
│  │  │     ╱\   P1                    ╱\                   │  │ │
│  │  │    ╱  \  ──── P2          ╱\  ╱  \                  │  │ │
│  │  │   ╱    ╲╱   ╲           ╱  ╲╱    ╲                 │  │ │
│  │  │  ╱           ╲     ╱───╱         ╲                 │  │ │
│  │  │ ╱             ╲───╱               ╲___             │  │ │
│  │  └─────────────────────────────────────────────────────┘  │ │
│  │  (click graph to jump to that moment in replay)           │ │
│  └────────────────────────────────────────────────────────────┘ │
│                                                                  │
│  SCORE SUMMARY                                                   │
│  ┌──────────────┬──────────┬──────────┐                         │
│  │              │ You      │ PlayerX  │                         │
│  ├──────────────┼──────────┼──────────┤                         │
│  │ Units Killed │ 47       │ 23       │                         │
│  │ Units Lost   │ 31       │ 52       │                         │
│  │ Structures   │ 3 / 1    │ 1 / 5    │  (destroyed / lost)    │
│  │ Income Total │ $14,200  │ $11,800  │                         │
│  │ APM (avg)    │ 86       │ 62       │                         │
│  └──────────────┴──────────┴──────────┘                         │
│                                                                  │
│  [Watch Replay]  [Share]  [Export Summary]                        │
└──────────────────────────────────────────────────────────────────┘

Tabs:

• Overview: Army value graph, score summary, key moments timeline
• Economy: Income graph, unspent resources graph, harvester count graph, total earned/spent
• Military: Per-unit-type kill/death/efficiency table, army composition pie charts at key moments
• Build Order: Side-by-side production timelines per player (adapted from SC2 Game Summary)
• Heatmaps: Unit death, combat, camera attention, economy heatmaps on minimap view

All graphs are clickable — click a point to open the Replay Viewer at that timestamp.

Replay Sharing

Match ID System (Dota 2 Pattern)

Relay-hosted matches generate a unique Match ID (short alphanumeric hash, e.g., IC-7K3M9X). Any player can enter this ID in the replay browser to download the replay.

• Copy Match ID: Available in post-game screen, replay browser detail panel, and profile match history
• [Enter Match ID…] in replay browser: text field → download from relay → add to local library
• URL format: ic://replay/IC-7K3M9X — opens IC directly to the replay (OS URL scheme handler)
• Availability: Relay-hosted replays persist for a configurable period (default: 90 days, server-operator configurable via D072). After expiry, only locally-saved copies remain.
• Privacy: Match IDs for ranked games are public by default. Custom/private games generate IDs only if the host enables sharing.

File-Based Sharing

• .icrep files are portable and self-describing
• Embedded resources mode (see formats/save-replay-formats.md § “Embedded Resources”): Self-contained replays that include the map and rule snapshots, so the recipient does not need matching content installed
• File association: .icrep registered with the OS; double-click opens IC’s replay viewer
• Drag-and-drop: Drop an .icrep file onto the IC window to open it

Workshop Integration

• Community replays can be published to the Workshop as curated collections (e.g., “Best Games of Season 3”, “Teaching Replays: Soviet Openings”)
• Workshop replay packs include metadata for browsing without downloading every replay file
• Creators can attach commentary notes to published replays

P2P Distribution

For popular replays (tournament finals, community highlights), p2p-distribute forms a swarm — the relay seeds initially, and subsequent downloaders become peers. This scales replay distribution without relay storage costs growing linearly with demand.

• Match ID replays: Relay is the initial seed; swarm forms on demand at user-requested priority
• Workshop replay packs: Standard Workshop P2P distribution (D049) at user-requested priority; dependency resolution ensures the viewer has matching mods/maps
• Piece alignment: .icrep per-256-tick LZ4 chunks align with P2P piece boundaries where practical, enabling streaming playback (start watching before full download)

See D049 § Replay Sharing for the full P2P distribution design.

Video / Clip Export

IC ships with built-in .webm video export — ahead of every RTS surveyed except LoL’s basic clip system.

Quick Clip

During replay playback:

1. Press Ctrl+Shift+R or click [Clip] to start recording
2. The transport bar shows a red recording indicator and elapsed clip time
3. Press Ctrl+Shift+R again to stop
4. Clip saved to Replays/Clips/ as .webm (VP9 video + Opus audio)
5. Toast notification: Clip saved (12s) — [Open Folder] [Copy to Clipboard]

Full Replay Export

From replay browser or viewer menu: [Export Video…]

┌─────────────────────────────────────────────────────────────────┐
│  EXPORT REPLAY VIDEO                                             │
│                                                                 │
│  Range: [Full Replay ▾]  or  Start: [00:00] End: [12:34]        │
│                                                                 │
│  Resolution: [1920×1080 ▾]   Framerate: [60 fps ▾]              │
│  Quality:    [High ▾]        Format: [.webm (VP9) ▾]            │
│                                                                 │
│  Camera:  [Current camera settings ▾]                            │
│           (Free Camera / Player 1 / Player 2 / Directed)         │
│                                                                 │
│  Include:  ☑ Observer overlays   ☑ Transport bar (off for clean) │
│            ☑ Voice audio         ☑ Game audio                    │
│                                                                 │
│  Estimated size: ~180 MB   Estimated time: ~3 min                │
│                                                                 │
│  [Export]  [Cancel]                                               │
└─────────────────────────────────────────────────────────────────┘

Render pipeline: The export runs the replay at accelerated speed off-screen, capturing frames to the encoder. This allows higher-quality output than screen capture and works headless.

Cinematic Camera Tools

For content creators and community filmmakers. Accessible via replay viewer menu → [Cinematic Mode] or Ctrl+Shift+C.

Camera Path Editor

Define a camera path with keyframes:

• Place keyframes at positions along the timeline (Ctrl+K to add keyframe at current camera position and tick)
• Each keyframe stores: camera position, zoom, rotation (for 3D render mode), playback speed at that point
• Camera interpolates smoothly between keyframes (Catmull-Rom spline)
• Preview the path before recording
• Export the camera path as a reusable .iccam file

Lens Controls (3D Render Mode, D048)

When using 3D render mode:

Cinematic Toggles

Moddable Observer UI

The observer overlay system is data-driven and moddable (SC2 custom observer UI pattern). Community creators can publish custom observer layouts via the Workshop.

• Observer panel layouts are defined in YAML (position, size, data bindings, conditional visibility)
• The game provides a standardized data API that observer panels read from (player stats, army composition, economy, production, APM)
• Built-in layouts: Default, Compact, Caster Broadcast
• Workshop layouts installable and selectable from replay viewer settings
• Layout switching is instant (no reload required)

This enables community-created broadcast overlays (equivalent to SC2’s WCS Observer and AhliObs) without engine modifications.

Live Spectator Mode

Live spectating shares the same viewer infrastructure as replay playback, with these differences:

Mid-Game Spectator Join

Unlike OpenRA (which cannot do this), IC’s relay architecture supports spectators joining a match in progress:

1. Spectator requests join via relay
2. Relay sends current state snapshot + recent order backlog
3. Client re-simulates from snapshot to catch up
4. Spectator enters live stream with <5 second catch-up delay

Spectator Slots

• Visible in lobby with spectator count / max slots
• Separate from player slots
• Lobby host configures: max spectators, fog-of-war policy, broadcast delay
• Tournament mode: spectator slots may require organizer approval

Foreign Replay Playback (D056)

Imported replays (OpenRA .orarep, Remastered Collection) play through the same viewer with additional UX:

Divergence Confidence Indicator

A small badge in the transport bar shows the current divergence confidence level:

The badge is clickable to show a detail panel with divergence metrics and explanation.

Limitations Banner

Foreign replays show a subtle top banner on first load:

This replay was imported from {OpenRA / Remastered}. Playback uses translated
orders and may differ from the original. [Learn More] [Dismiss]

Replay Anonymization

ic replay anonymize <file> (CLI) or Replay Browser → right-click → [Anonymize…]:

• Replace player names with generic labels (Player 1, Player 2, etc.)
• Strip voice tracks
• Strip chat messages
• Preserve all gameplay data (orders, events, state hashes)
• Useful for educational content sharing, tournament review, and privacy

Replay Settings

Accessible via [Settings] gear icon in the transport bar:

Platform Adaptations

Cross-References