I know it may be a small group but should anyone (else) be interested in a CLI Tool that can be used to change the preset on a MacBook with a Retina display, a Studio Display, and/or a Pro Display XDR, the following file does the trick (far easier and faster than stepping through Control Center or System Settings)!
It works very well!
import Foundation
import ObjectiveC
// Define the function type for the CoreDisplay transaction lookups
typealias TransactionFunc = @convention(c) () -> Void
class ReferenceDisplay {
let id: CGDirectDisplayID
init(id: CGDirectDisplayID) { self.id = id }
func set(preset: MPDisplayPreset) {
// 1. Load CoreDisplay to manage hardware transactions
let cdHandle = dlopen("/System/Library/Frameworks/CoreDisplay.framework/CoreDisplay", RTLD_NOW)
let beginTx = dlsym(cdHandle, "CoreDisplay_Display_BeginTransaction").map { unsafeBitCast($0, to: TransactionFunc.self) }
let endTx = dlsym(cdHandle, "CoreDisplay_Display_EndTransaction").map { unsafeBitCast($0, to: TransactionFunc.self) }
print("🔗 Opening Hardware Transaction...")
beginTx?()
if let manager = MPDisplayMgr(),
let mpDisplay = (manager as AnyObject).display(withID: Int32(self.id)) {
let obj = mpDisplay as AnyObject
// The "Winning" selector we found via introspection
let hwSelector = NSSelectorFromString("setActivePreset:")
if obj.responds(to: hwSelector) {
print("📡 Triggering hardware switch via setActivePreset:...")
_ = obj.perform(hwSelector, with: preset)
} else {
print("⚠️ setActivePreset: not found, falling back to setPreset:")
_ = obj.perform(NSSelectorFromString("setPreset:"), with: preset)
}
// Sync the Manager state so System Settings stays in step
let mgrObj = manager as AnyObject
let mgrSel = NSSelectorFromString("setPreset:forDisplay:")
if mgrObj.responds(to: mgrSel) {
_ = mgrObj.perform(mgrSel, with: preset, with: mpDisplay)
}
}
endTx?()
print("✅ Hardware Transaction Committed.")
if let h = cdHandle { dlclose(h) }
}
}
// --- Execution Logic ---
let displayID = CGMainDisplayID()
let display = ReferenceDisplay(id: displayID)
guard let manager = MPDisplayMgr(),
let mpDisplay = (manager as AnyObject).display(withID: Int32(displayID)) else {
print("❌ Error: Could not initialize Display Manager.")
exit(1)
}
// Get available presets
let presetsSelector = NSSelectorFromString("presets")
let unmanagedPresets = (mpDisplay as AnyObject).perform(presetsSelector)
guard let allPresets = unmanagedPresets?.takeUnretainedValue() as? [MPDisplayPreset] else {
print("❌ Error: Could not load presets.")
exit(1)
}
if CommandLine.arguments.count < 2 {
print("✅ Main Display ID: \(displayID)")
print("Usage: ./ReferencePreset \"Preset Name\"")
print("Available Presets:")
allPresets.forEach { p in
if let name = p.presetName { print(" - \"\(name)\"") }
}
exit(0)
}
let targetName = CommandLine.arguments[1]
if let targetPreset = allPresets.first(where: { $0.presetName == targetName }) {
print("🚀 Target Preset: \(targetName)")
display.set(preset: targetPreset)
// Final notification broadcast to update the macOS Control Center and UI
let note = NSNotification.Name("com.apple.ControlCenter.DisplayChanged")
DistributedNotificationCenter.default().postNotificationName(note, object: nil, userInfo: nil, deliverImmediately: true)
} else {
print("❌ Preset '\(targetName)' not found.")
}
