SlighRes

A lightweight, native macOS menu-bar app for switching display resolutions on Apple Silicon Macs.

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Features

• Menu-bar only — no Dock icon, always one click away.
• All displays — built-in and external monitors listed automatically.
• Smart labels — model name + serial for disambiguation of identical monitors.
• One-click switch — pick a resolution and it applies immediately.
• 10-second safety revert — if you can’t see or dismiss the confirmation dialog, the previous resolution is restored automatically.
• Hot-plug aware — displays added or removed update the menu in real time.
• HiDPI badge — Retina modes clearly marked.

Requirements

Requirement	Value
macOS	14.0 (Sonoma) or later
Architecture	Apple Silicon (arm64)
Xcode	15.0+

Build & Run

Option A — Xcode

1. Open SlighRes.xcodeproj in Xcode 15+.
2. Select the SlighRes scheme and My Mac destination.
3. Product → Run (⌘R).
4. The app appears as a display icon (🖥) in the menu bar.

Option B — Command-line

xcodebuild -project SlighRes.xcodeproj \
           -scheme SlighRes \
           -configuration Release \
           -arch arm64 \
           build

The built .app bundle lands in the derived-data build directory.

Option C — Swift Package Manager (alternative)

If you prefer SPM over the Xcode project, create a Package.swift at the repo root:

// swift-tools-version:5.9
import PackageDescription

let package = Package(
    name: "SlighRes",
    platforms: [.macOS(.v14)],
    targets: [
        .executableTarget(
            name: "SlighRes",
            path: "SlighRes/Sources",
            resources: [
                .process("../Resources/Assets.xcassets")
            ]
        )
    ]
)

Then swift build.

Project Structure

SlighRes/
├── Sources/
│   ├── App/
│   │   └── SlighResApp.swift        # @main entry, MenuBarExtra + Settings
│   ├── Models/
│   │   ├── DisplayInfo.swift        # Per-display model
│   │   └── DisplayMode.swift        # Per-resolution model
│   ├── Services/
│   │   ├── DisplayService.swift     # CoreGraphics wrapper
│   │   └── RevertSafetyManager.swift # 10-sec countdown + revert
│   ├── ViewModels/
│   │   └── DisplayViewModel.swift   # @Observable state
│   └── Views/
│       ├── MenuBarView.swift        # Main dropdown UI
│       └── SettingsView.swift       # Preferences window
├── Resources/
│   └── Assets.xcassets/             # App icon, accent colour
├── Info.plist
└── SlighRes.entitlements

How It Works

1. On launch the app enumerates active displays via CGGetActiveDisplayList.
2. For each display it reads modes with CGDisplayCopyAllDisplayModes and filters to usable, deduplicated modes.
3. The menu shows each display as a section; clicking a mode calls CGConfigureDisplayWithDisplayMode.
4. After a switch, RevertSafetyManager shows an NSAlert with a 10-second countdown. If the user doesn’t click Keep, the previous mode is restored.
5. A CGDisplayReconfigurationCallback fires whenever displays are connected, disconnected, or reconfigured — the menu refreshes automatically.

Signing & Notarization

See docs/SIGNING.md for details. TL;DR:

• For personal use, ad-hoc signing is fine:

  codesign --force --deep --sign - SlighRes.app

• For sharing, sign with a Developer ID certificate and notarize with notarytool.

License

Personal use. No warranty.