Add Tern hardware brightness and Night Vision controls

.github/workflows/verify.yml

@@ -0,0 +1,33 @@
+name: Verify
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+  workflow_dispatch:
+
+permissions:
+  contents: read
+
+concurrency:
+  group: verify-${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  build-and-test:
+    runs-on: macos-26
+    timeout-minutes: 20
+    steps:
+      - uses: actions/checkout@11d5960a326750d5838078e36cf38b85af677262 # v4
+      - name: Use newest installed Xcode
+        run: sudo xcode-select -s "$(ls -d /Applications/Xcode*.app | sort -V | tail -1)" && swift --version
+      - name: Install XcodeGen
+        run: brew list xcodegen >/dev/null 2>&1 || brew install xcodegen
+      - name: Build DDC helper from source
+        run: ./scripts/build-ddc.sh
+      - name: Verify live DDC scheduling without hardware
+        run: ./tools/test-tern-ddc.sh
+      - name: Generate Xcode project
+        run: xcodegen generate
+      - name: Build and run tests
+        run: xcodebuild -project XDR.xcodeproj -scheme XDR -destination 'platform=macOS' -derivedDataPath build CODE_SIGNING_ALLOWED=NO test

.gitignore

@@ -2,3 +2,12 @@ build/
 .DS_Store
 xcuserdata/
 *.xcuserstate
+
+# Generated DDC helper and local package caches
+XDR/Resources/m1ddc
+Vendor/m1ddc/.objects/
+Vendor/m1ddc/m1ddc
+Vendor/m1ddc/library/
+.build/
+DerivedData/
+.swiftpm/

README.md

@@ -1,26 +1,39 @@
 # XDR
 
-Mac menu-bar brightness for HDR and Pro Display XDR. Goes brighter than the system slider. Drag it, the screen follows, color gamut stays put.
+A native Mac menu-bar app for display brightness, MacBook XDR boost and Night Vision.
 
-## What It Does
+## Controls
 
-XDR gives you real-time brightness control for high-dynamic-range displays. Click the menu bar icon, adjust the slider, and your display brightness changes immediately while keeping the color gamut intact. No fiddling through system settings. No overshooting.
+- Built-in XDR displays retain their native brightness and boost controls.
+- The identified Tern 16-inch 4K IPS monitor uses a hardware brightness slider over USB-C DDC. It does not use gamma dimming or simulate XDR boost.
+- Other unsupported external displays retain the software-dimming route.
+- Night Vision provides a red viewing mode. Boost and Night Vision change appearance; neither is a colour-calibration tool.
 
-Real example: You're editing photos in Final Cut Pro on a ProDisplay XDR in a bright room. Your edit suite is getting washed out. You tap the menu bar, bump the brightness up 20%, colors stay perfect, you're back to work in two seconds.
+The Tern slider updates its saved reconnect preset after the monitor confirms the value. The optional local reconnect helper is independent of this app; configuring it is not required to use the slider. Its saved preset is stored in `~/Library/Application Support/Tern Controls/defaults.json`.
 
-## Why This Matters
+## Build
 
-macOS gives you global brightness control, but HDR displays need something smarter. They use display gamma tables to adjust intensity while preserving the wide color gamut that makes them worth owning. XDR handles this directly, so you get precise control without losing the color accuracy that HDR is for.
+Requires macOS 14 or later, Xcode and XcodeGen. Tern hardware control currently targets Apple Silicon Macs and the explicitly identified monitor.
 
-The slider is live. No confirmation dialogs. No lag. Adjust and see.
+```sh
+./scripts/build-ddc.sh
+xcodegen generate
+xcodebuild -project XDR.xcodeproj -scheme XDR -configuration Release \
+  -derivedDataPath build CODE_SIGN_IDENTITY=- CODE_SIGN_STYLE=Manual build
+```
 
-## How It Works
+The DDC helper is built from the MIT-licensed source in `Vendor/m1ddc`; its executable is generated, not committed. KeyboardShortcuts and LaunchAtLogin are resolved through Swift Package Manager.
 
-- **SwiftUI menu bar** for the UI
-- **macOS display gamma tables** for the actual brightness adjustment
-- **Real-time response** as you drag
-- **Persistent settings** that survive a restart
+## Verify
 
-## Get Started
+The fast DDC scheduler regression uses a fake monitor process, so it can run without a physical display.
 
-Launch it, click the menu bar icon, adjust the slider. Your brightness setting is saved automatically.
+```sh
+./tools/test-tern-ddc.sh
+./scripts/build-ddc.sh
+xcodegen generate
+xcodebuild -project XDR.xcodeproj -scheme XDR -destination 'platform=macOS' \
+  -derivedDataPath build CODE_SIGNING_ALLOWED=NO test
+```
+
+Automated tests do not establish physical brightness, speaker playback, colour accuracy or persistence after a monitor loses power. Hardware changes should be checked against monitor readback and the actual display.

Tests/NightVisionMathTests.swift

@@ -0,0 +1,146 @@
+import XCTest
+@testable import XDR
+
+final class NightVisionMathTests: XCTestCase {
+
+    // MARK: - Channel ceilings (gamma LUT model)
+
+    func testCeilings_endpoints() {
+        // Zero intensity is identity: every channel at full ceiling.
+        XCTAssertEqual(NightVisionCurve.redMax(forIntensity: 0), 1.0, accuracy: 0.0001)
+        XCTAssertEqual(NightVisionCurve.greenMax(forIntensity: 0), 1.0, accuracy: 0.0001)
+        XCTAssertEqual(NightVisionCurve.blueMax(forIntensity: 0), 1.0, accuracy: 0.0001)
+        // Full intensity hits the floors.
+        XCTAssertEqual(NightVisionCurve.redMax(forIntensity: 1), NightVisionCurve.minRed, accuracy: 0.0001)
+        XCTAssertEqual(NightVisionCurve.greenMax(forIntensity: 1), NightVisionCurve.minGreen, accuracy: 0.0001)
+        XCTAssertEqual(NightVisionCurve.blueMax(forIntensity: 1), NightVisionCurve.minBlue, accuracy: 0.0001)
+    }
+
+    func testGreenAndBlue_monotonicallyDecrease() {
+        var lastG = 2.0, lastB = 2.0
+        for t in stride(from: 0.0, through: 1.0, by: 0.05) {
+            let g = NightVisionCurve.greenMax(forIntensity: t)
+            let b = NightVisionCurve.blueMax(forIntensity: t)
+            XCTAssertLessThanOrEqual(g, lastG + 0.0001, "green must not increase as intensity rises")
+            XCTAssertLessThanOrEqual(b, lastB + 0.0001, "blue must not increase as intensity rises")
+            lastG = g; lastB = b
+        }
+    }
+
+    func testBlueSuppressedHarderThanGreen() {
+        // Blue is the worst offender for dark adaptation, so it is always the
+        // most suppressed channel.
+        for t in stride(from: 0.1, through: 1.0, by: 0.1) {
+            XCTAssertLessThan(NightVisionCurve.blueMax(forIntensity: t),
+                              NightVisionCurve.greenMax(forIntensity: t) + 0.0001,
+                              "blue ceiling should be <= green at intensity \(t)")
+        }
+    }
+
+    func testRed_staysDominant() {
+        // Red is the surviving channel: once the shift is meaningfully engaged its
+        // ceiling sits well above green/blue. (The low end is intentionally gentle —
+        // a "warm Night Shift" — so dominance is asserted from mid-intensity up.)
+        for t in stride(from: 0.6, through: 1.0, by: 0.1) {
+            XCTAssertGreaterThan(NightVisionCurve.redMax(forIntensity: t),
+                                 NightVisionCurve.greenMax(forIntensity: t) + 0.2)
+            XCTAssertGreaterThan(NightVisionCurve.redMax(forIntensity: t),
+                                 NightVisionCurve.blueMax(forIntensity: t) + 0.2)
+        }
+    }
+
+    func testRed_onlyDimsAtTop() {
+        // The lower two thirds keep full red brightness; only the deep end dims.
+        XCTAssertEqual(NightVisionCurve.redMax(forIntensity: 0.3), 1.0, accuracy: 0.0001)
+        XCTAssertEqual(NightVisionCurve.redMax(forIntensity: 0.7), 1.0, accuracy: 0.0001)
+        XCTAssertLessThan(NightVisionCurve.redMax(forIntensity: 1.0), 1.0)
+        XCTAssertGreaterThanOrEqual(NightVisionCurve.redMax(forIntensity: 1.0), 0.75) // never too dark
+    }
+
+    func testReadabilityFloors_atFullIntensity() {
+        // The contract that prevents an illegible result: at maximum, green and
+        // blue keep a trace so edges stay distinguishable, red stays bright.
+        XCTAssertGreaterThanOrEqual(NightVisionCurve.greenMax(forIntensity: 1.0), 0.09)
+        XCTAssertGreaterThanOrEqual(NightVisionCurve.blueMax(forIntensity: 1.0), 0.025)
+        XCTAssertGreaterThanOrEqual(NightVisionCurve.redMax(forIntensity: 1.0), 0.78)
+    }
+
+    func testWarmZone_isGentle() {
+        // At 35% (the first-enable default) the shift is mild: green and blue
+        // ceilings stay high so the screen reads like a warm Night Shift.
+        XCTAssertGreaterThan(NightVisionCurve.greenMax(forIntensity: 0.35), 0.70)
+        XCTAssertGreaterThan(NightVisionCurve.blueMax(forIntensity: 0.35), 0.55)
+        XCTAssertEqual(NightVisionCurve.redMax(forIntensity: 0.35), 1.0, accuracy: 0.0001)
+    }
+
+    func testInputsAreClamped() {
+        XCTAssertEqual(NightVisionCurve.greenMax(forIntensity: -1), 1.0, accuracy: 0.0001)
+        XCTAssertEqual(NightVisionCurve.greenMax(forIntensity: 2), NightVisionCurve.minGreen, accuracy: 0.0001)
+        XCTAssertEqual(NightVisionCurve.blueMax(forIntensity: 2), NightVisionCurve.minBlue, accuracy: 0.0001)
+        XCTAssertEqual(NightVisionCurve.redMax(forIntensity: 2), NightVisionCurve.minRed, accuracy: 0.0001)
+    }
+
+    // MARK: - Overlay fallback values
+
+    func testWashAlpha_endpointsAndMonotonic() {
+        XCTAssertEqual(NightVisionCurve.washAlpha(forIntensity: 0), 0, accuracy: 0.0001)
+        XCTAssertGreaterThan(NightVisionCurve.washAlpha(forIntensity: 1), 0.4)
+        var last = -1.0
+        for t in stride(from: 0.0, through: 1.0, by: 0.05) {
+            let v = NightVisionCurve.washAlpha(forIntensity: t)
+            XCTAssertGreaterThanOrEqual(v, last)
+            last = v
+        }
+    }
+
+    func testDimAlpha_belowThreshold_isZero() {
+        XCTAssertEqual(NightVisionCurve.dimAlpha(forIntensity: 0.0), 0, accuracy: 0.0001)
+        XCTAssertEqual(NightVisionCurve.dimAlpha(forIntensity: 0.6), 0, accuracy: 0.0001)
+    }
+
+    func testDimAlpha_atFull_isModest() {
+        let d = NightVisionCurve.dimAlpha(forIntensity: 1.0)
+        XCTAssertGreaterThan(d, 0)
+        XCTAssertLessThanOrEqual(d, 0.35) // dims, never blacks out
+    }
+
+    // MARK: - Engage ramp
+
+    func testRampProgress_endpointsAndEased() {
+        XCTAssertEqual(NightVisionCurve.rampProgress(0), 0, accuracy: 0.0001)
+        XCTAssertEqual(NightVisionCurve.rampProgress(1), 1, accuracy: 0.0001)
+        XCTAssertLessThan(NightVisionCurve.rampProgress(0.1), 0.1)
+        XCTAssertGreaterThan(NightVisionCurve.rampProgress(0.9), 0.9)
+        var last = -1.0
+        for t in stride(from: 0.0, through: 1.0, by: 0.05) {
+            let v = NightVisionCurve.rampProgress(t)
+            XCTAssertGreaterThanOrEqual(v, last)
+            last = v
+        }
+    }
+
+    // MARK: - Safe restore rule
+
+    func testSafeRestore_disabledStaysDisabled() {
+        let r = NightVision.safeRestore(enabled: false, intensity: 0.5)
+        XCTAssertFalse(r.enabled)
+        XCTAssertEqual(r.intensity, 0.5, accuracy: 0.0001)
+    }
+
+    func testSafeRestore_withinCeiling_staysEnabled() {
+        XCTAssertTrue(NightVision.safeRestore(enabled: true, intensity: 0.5).enabled)
+        XCTAssertTrue(NightVision.safeRestore(enabled: true, intensity: NightVision.safeRestoreCeiling).enabled)
+    }
+
+    func testSafeRestore_extremeRestoresOffButKeepsIntensity() {
+        let r = NightVision.safeRestore(enabled: true, intensity: 0.9)
+        XCTAssertFalse(r.enabled)
+        XCTAssertEqual(r.intensity, 0.9, accuracy: 0.0001)
+        XCTAssertFalse(NightVision.safeRestore(enabled: true, intensity: 1.0).enabled)
+    }
+
+    func testFirstEnableDefault_isWarmZone() {
+        XCTAssertEqual(NightVision.firstEnableIntensity, 0.35, accuracy: 0.0001)
+        XCTAssertEqual(NightVisionCurve.redMax(forIntensity: NightVision.firstEnableIntensity), 1.0, accuracy: 0.0001)
+    }
+}

Vendor/m1ddc/LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2021 waydabber
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

Vendor/m1ddc/Makefile

@@ -0,0 +1,128 @@
+# -- VARIABLES
+
+# Project name
+NAME =		m1ddc
+LIB = 		lib$(NAME)
+
+# Compiler
+CC =		clang
+CFLAGS =	-Wall -Werror -Wextra -fmodules
+SDKROOT ?= $(shell xcrun --sdk macosx --show-sdk-path)
+CPPFLAGS =	-I $(INC_DIR) -isysroot "$(SDKROOT)"
+DEPFLAGS =	-MMD
+
+# Libraries
+LDLIBS =	-framework CoreDisplay -isysroot "$(SDKROOT)"
+
+# Commands
+RM =		rm -f
+RMDIR =		rm -rf
+MKDIR =		mkdir -p
+MAKE =		make -C
+AR =		ar -rcs
+
+# Paths
+INC_DIR =	headers
+SRC_DIR =	sources
+LIB_DIR =	library
+BIN_DIR =	/usr/local/bin
+
+# Sources & Objects - Binary
+SOURCES =	i2c \
+			ioregistry \
+			m1ddc \
+
+OBJ_DIR =	.objects
+OBJECTS = 	$(patsubst %,$(OBJ_DIR)/%,$(SOURCES:=.o))
+
+# Sources & Objects - Library
+LIB_SRCS = 	$(filter-out m1ddc, $(SOURCES))
+LIB_OBJS = 	$(patsubst %,$(OBJ_DIR)/%,$(LIB_SRCS:=.o))
+LIB_HDRS = 	$(patsubst %,$(INC_DIR)/%,$(LIB_SRCS:=.h))
+
+# -- IMPLICIT RULES / LINKING
+
+$(OBJ_DIR)/%.o: $(SRC_DIR)/%.m Makefile
+	@$(CC) -c $< -o $@ $(CPPFLAGS) $(CFLAGS) $(DEPFLAGS)
+
+$(OBJ_DIR):
+	@$(MKDIR) $(OBJ_DIR)
+
+$(LIB_DIR):
+	@$(MKDIR) $(LIB_DIR)
+
+$(NAME): $(OBJ_DIR) $(OBJECTS)
+	@$(CC) $(LDLIBS) $(OBJECTS) -o $@
+	@printf "Created binary \"$(NAME)\"\n"
+
+$(LIB).a: $(LIB_DIR) $(OBJ_DIR) $(LIB_OBJS)
+	@$(AR) $(LIB_DIR)/$@ $(LIB_OBJS)
+	@printf "Created library \"$(LIB_DIR)/$@\"\n"
+
+# For each header file, we do the following, using regular expressions:
+# - Ignore the #ifndef _FILE/# define _FILE/#endif directives that begin/end the file
+# - Extract the #import directives
+# - Extract all the remaining # directives
+# - Extract the rest: types and functions declarations.
+# All the extracted lines are then appendend to the final header file.
+$(LIB).h: $(LIB_DIR) $(LIB_HDRS)
+	@imports=""; \
+	directives=""; \
+	declarations=""; \
+	for file in $(LIB_HDRS); do \
+		declarations="$$declarations\n\n/*\n * -- $$(basename $$file .h | tr '[:lower:]' '[:upper:]')\n*/\n"; \
+		fileguard=$$(echo "_$$(basename $$file .h | tr '[:lower:]' '[:upper:]')_H"); \
+		if [ "$$(head -n 1 $$file)" = "#ifndef $$fileguard" ]; then \
+			filecontent=$$(sed -e '1,2d' -e '$$d' $$file); \
+		else \
+			filecontent=$$(cat $$file); \
+		fi; \
+		imports="$$imports\n$$(echo "$$filecontent" | grep -E "^#\s*import" | sort | uniq)"; \
+		directives="$$directives\n$$(echo "$$filecontent" | grep -E "^#" | grep -vE "^#\s*import" | grep -vE "^#\s*include\s*\".*.h\"$$" )"; \
+		declarations="$$declarations\n$$(echo "$$filecontent" | grep -vE "^#" )"; \
+	done; \
+	guard=$$(echo "_$(LIB)_H" | tr '[:lower:]' '[:upper:]'); \
+	printf "#ifndef $$guard\n# define $$guard\n\n" > $(LIB_DIR)/$@; \
+	printf "$$directives\n\n" >> $(LIB_DIR)/$@; \
+	printf "$$imports\n\n" >> $(LIB_DIR)/$@; \
+	printf "$$declarations\n\n" >> $(LIB_DIR)/$@; \
+	printf "#endif" >> $(LIB_DIR)/$@; \
+	sed -i '' -e '/^$$/N;/^\n$$/D' $(LIB_DIR)/$@; \
+
+	@printf "Created header \"$(LIB_DIR)/$@\"\n"
+
+# -- RULES
+
+.DEFAULT_GOAL := binary
+
+all: binary lib
+
+binary: $(NAME)
+
+lib: $(LIB).a $(LIB).h
+
+clean:
+	@if [ -e $(OBJ_DIR) ]; then \
+		$(RMDIR) $(OBJ_DIR); \
+		printf "Objects deleted\n"; \
+	fi;
+
+fclean: clean
+	@if [ -e $(NAME) ]; then \
+		$(RM) $(NAME); \
+		printf "Binary deleted\n"; \
+	fi;
+	@if [ -e $(LIB_DIR) ]; then \
+		$(RMDIR) $(LIB_DIR); \
+		printf "Library deleted\n"; \
+	fi;
+
+re: fclean all
+
+install:
+	/bin/mkdir -p $(BIN_DIR)
+	sudo /usr/bin/install -s -m 0755 $(NAME) $(BIN_DIR)
+
+.PHONY: all lib clean fclean re install
+
+-include $(OBJECTS:.o=.d)