fix: almost ready for fine tuning

Gaze/Constants/EyeTrackingConstants.swift

@@ -62,4 +62,20 @@ enum EyeTrackingConstants: Sendable {
     static let pixelGazeMinRatio: Double = 0.35  // Looking right threshold
     static let pixelGazeMaxRatio: Double = 0.65  // Looking left threshold
     static let pixelGazeEnabled: Bool = true
+    
+    // MARK: - Screen Boundary Detection (New)
+    
+    /// Forgiveness margin for the "gray area" around the screen edge.
+    /// 0.05 means the safe zone is extended by 5% of the range on each side.
+    /// If in the gray area, we assume the user is Looking Away (success).
+    static let boundaryForgivenessMargin: Double = 0.05
+    
+    /// Distance sensitivity factor.
+    /// 1.0 = Linear scaling (face width 50% smaller -> eye movement expected to be 50% smaller)
+    /// > 1.0 = More aggressive scaling
+    static let distanceSensitivity: Double = 1.0
+    
+    /// Minimum confidence required for a valid pupil detection before updating the gaze average.
+    /// Helps filter out blinks or noisy frames.
+    static let minimumGazeConfidence: Int = 3 // consecutive valid frames
 }

Gaze/Models/CalibrationData.swift

@@ -45,15 +45,15 @@ enum CalibrationStep: String, Codable, CaseIterable {
         case .farLeft:
             return "Look as far left as comfortable"
         case .left:
-            return "Look to the left"
+            return "Look to the left edge of the screen"
         case .farRight:
             return "Look as far right as comfortable"
         case .right:
-            return "Look to the right"
+            return "Look to the right edge of the screen"
         case .up:
-            return "Look up"
+            return "Look to the top edge of the screen"
         case .down:
-            return "Look down"
+            return "Look to the bottom edge of the screen"
         case .topLeft:
             return "Look to the top left corner"
         case .topRight:
@@ -70,42 +70,75 @@ struct GazeSample: Codable {
     let leftRatio: Double?
     let rightRatio: Double?
     let averageRatio: Double
+    let leftVerticalRatio: Double?
+    let rightVerticalRatio: Double?
+    let averageVerticalRatio: Double
+    let faceWidthRatio: Double? // For distance scaling (face width / image width)
     let timestamp: Date
     
-    init(leftRatio: Double?, rightRatio: Double?) {
+    init(leftRatio: Double?, rightRatio: Double?, leftVerticalRatio: Double? = nil, rightVerticalRatio: Double? = nil, faceWidthRatio: Double? = nil) {
         self.leftRatio = leftRatio
         self.rightRatio = rightRatio
+        self.leftVerticalRatio = leftVerticalRatio
+        self.rightVerticalRatio = rightVerticalRatio
+        self.faceWidthRatio = faceWidthRatio
         
-        // Calculate average from available ratios
+        // Calculate average horizontal ratio
         if let left = leftRatio, let right = rightRatio {
             self.averageRatio = (left + right) / 2.0
         } else {
             self.averageRatio = leftRatio ?? rightRatio ?? 0.5
         }
         
+        // Calculate average vertical ratio
+        if let left = leftVerticalRatio, let right = rightVerticalRatio {
+            self.averageVerticalRatio = (left + right) / 2.0
+        } else {
+            self.averageVerticalRatio = leftVerticalRatio ?? rightVerticalRatio ?? 0.5
+        }
+        
         self.timestamp = Date()
     }
 }
 
 struct GazeThresholds: Codable {
-    let minLeftRatio: Double   // Looking left threshold (e.g., 0.65)
+    // Horizontal Thresholds
-    let maxRightRatio: Double  // Looking right threshold (e.g., 0.35)
+    let minLeftRatio: Double   // Looking left (≥ value)
-    let centerMin: Double      // Center range minimum
+    let maxRightRatio: Double  // Looking right (≤ value)
-    let centerMax: Double      // Center range maximum
+    
+    // Vertical Thresholds
+    let minUpRatio: Double     // Looking up (≤ value, typically < 0.5)
+    let maxDownRatio: Double   // Looking down (≥ value, typically > 0.5)
+    
+    // Screen Bounds (Calibration Zone)
+    // Defines the rectangle of pupil ratios that correspond to looking AT the screen
+    let screenLeftBound: Double
+    let screenRightBound: Double
+    let screenTopBound: Double
+    let screenBottomBound: Double
+    
+    // Reference Data for Distance Scaling
+    let referenceFaceWidth: Double // Average face width during calibration
     
     var isValid: Bool {
-        // Ensure thresholds don't overlap
+        // Basic sanity checks
-        return maxRightRatio < centerMin &&
+        return maxRightRatio < minLeftRatio &&
-               centerMin < centerMax &&
+               minUpRatio < maxDownRatio &&
-               centerMax < minLeftRatio
+               screenRightBound < screenLeftBound && // Assuming lower ratio = right
+               screenTopBound < screenBottomBound // Assuming lower ratio = up
     }
     
     static var defaultThresholds: GazeThresholds {
         GazeThresholds(
             minLeftRatio: 0.65,
             maxRightRatio: 0.35,
-            centerMin: 0.40,
+            minUpRatio: 0.40,
-            centerMax: 0.60
+            maxDownRatio: 0.60,
+            screenLeftBound: 0.60,
+            screenRightBound: 0.40,
+            screenTopBound: 0.45,
+            screenBottomBound: 0.55,
+            referenceFaceWidth: 0.0 // 0.0 means unused/uncalibrated
         )
     }
 }
@@ -137,62 +170,95 @@ struct CalibrationData: Codable {
     func averageRatio(for step: CalibrationStep) -> Double? {
         let stepSamples = getSamples(for: step)
         guard !stepSamples.isEmpty else { return nil }
-        
+        return stepSamples.reduce(0.0) { $0 + $1.averageRatio } / Double(stepSamples.count)
-        let sum = stepSamples.reduce(0.0) { $0 + $1.averageRatio }
-        return sum / Double(stepSamples.count)
     }
     
-    func standardDeviation(for step: CalibrationStep) -> Double? {
+    func averageVerticalRatio(for step: CalibrationStep) -> Double? {
         let stepSamples = getSamples(for: step)
-        guard stepSamples.count > 1, let mean = averageRatio(for: step) else { return nil }
+        guard !stepSamples.isEmpty else { return nil }
+        return stepSamples.reduce(0.0) { $0 + $1.averageVerticalRatio } / Double(stepSamples.count)
+    }
     
-        let variance = stepSamples.reduce(0.0) { sum, sample in
+    func averageFaceWidth(for step: CalibrationStep) -> Double? {
-            let diff = sample.averageRatio - mean
+        let stepSamples = getSamples(for: step)
-            return sum + (diff * diff)
+        let validSamples = stepSamples.compactMap { $0.faceWidthRatio }
-        } / Double(stepSamples.count - 1)
+        guard !validSamples.isEmpty else { return nil }
-        
+        return validSamples.reduce(0.0, +) / Double(validSamples.count)
-        return sqrt(variance)
     }
     
     mutating func calculateThresholds() {
-        // Need at least center, left, and right samples
+        // We need Center, Left, Right, Up, Down samples for a full calibration
-        guard let centerMean = averageRatio(for: .center),
+        // Fallback: If corners (TopLeft, etc.) are available, use them to reinforce bounds
-              let leftMean = averageRatio(for: .left),
-              let rightMean = averageRatio(for: .right) else {
-            print("⚠️ Insufficient calibration data to calculate thresholds")
-            return
-        }
         
-        let centerStdDev = standardDeviation(for: .center) ?? 0.05
+        let centerH = averageRatio(for: .center) ?? 0.5
+        let centerV = averageVerticalRatio(for: .center) ?? 0.5
         
-        // Calculate center range (mean ± 0.5 * std_dev)
+        // 1. Horizontal Bounds
-        let centerMin = max(0.0, centerMean - 0.5 * centerStdDev)
+        // If specific Left/Right steps missing, try corners
-        let centerMax = min(1.0, centerMean + 0.5 * centerStdDev)
+        let leftH = averageRatio(for: .left) ?? averageRatio(for: .topLeft) ?? averageRatio(for: .bottomLeft) ?? (centerH + 0.15)
+        let rightH = averageRatio(for: .right) ?? averageRatio(for: .topRight) ?? averageRatio(for: .bottomRight) ?? (centerH - 0.15)
         
-        // Calculate left threshold (midpoint between center and left extremes)
+        // 2. Vertical Bounds
-        let minLeftRatio = centerMax + (leftMean - centerMax) * 0.5
+        let upV = averageVerticalRatio(for: .up) ?? averageVerticalRatio(for: .topLeft) ?? averageVerticalRatio(for: .topRight) ?? (centerV - 0.15)
+        let downV = averageVerticalRatio(for: .down) ?? averageVerticalRatio(for: .bottomLeft) ?? averageVerticalRatio(for: .bottomRight) ?? (centerV + 0.15)
         
-        // Calculate right threshold (midpoint between center and right extremes)
+        // 3. Face Width Reference (average of all center samples)
-        let maxRightRatio = centerMin - (centerMin - rightMean) * 0.5
+        let refFaceWidth = averageFaceWidth(for: .center) ?? 0.0
         
-        // Validate and adjust if needed
+        // 4. Compute Boundaries with Margin
-        var thresholds = GazeThresholds(
+        // "Screen Bound" is exactly where the user looked.
-            minLeftRatio: min(0.95, max(0.55, minLeftRatio)),
+        // We set thresholds slightly BEYOND that to detect "Looking Away".
-            maxRightRatio: max(0.05, min(0.45, maxRightRatio)),
+        
-            centerMin: centerMin,
+        // Note: Assuming standard coordinates where:
-            centerMax: centerMax
+        // Horizontal: 0.0 (Right) -> 1.0 (Left)
+        // Vertical: 0.0 (Up) -> 1.0 (Down)
+        
+        // Thresholds for "Looking Away"
+        // Looking Left = Ratio > Screen Left Edge
+        let lookLeftThreshold = leftH + 0.05
+        // Looking Right = Ratio < Screen Right Edge
+        let lookRightThreshold = rightH - 0.05
+        
+        // Looking Up = Ratio < Screen Top Edge
+        let lookUpThreshold = upV - 0.05
+        // Looking Down = Ratio > Screen Bottom Edge
+        let lookDownThreshold = downV + 0.05
+        
+        let thresholds = GazeThresholds(
+            minLeftRatio: lookLeftThreshold,
+            maxRightRatio: lookRightThreshold,
+            minUpRatio: lookUpThreshold,
+            maxDownRatio: lookDownThreshold,
+            screenLeftBound: leftH,
+            screenRightBound: rightH,
+            screenTopBound: upV,
+            screenBottomBound: downV,
+            referenceFaceWidth: refFaceWidth
         )
         
-        // Ensure no overlap
-        if !thresholds.isValid {
-            print("⚠️ Computed thresholds overlap, using defaults")
-            thresholds = GazeThresholds.defaultThresholds
-        }
-        
         self.computedThresholds = thresholds
         print("✓ Calibration thresholds calculated:")
-        print("  Left: ≥\(String(format: "%.3f", thresholds.minLeftRatio))")
+        print("  H-Range: \(String(format: "%.3f", rightH)) to \(String(format: "%.3f", leftH))")
-        print("  Center: \(String(format: "%.3f", thresholds.centerMin))-\(String(format: "%.3f", thresholds.centerMax))")
+        print("  V-Range: \(String(format: "%.3f", upV)) to \(String(format: "%.3f", downV))")
-        print("  Right: ≤\(String(format: "%.3f", thresholds.maxRightRatio))")
+        print("  Ref Face Width: \(String(format: "%.3f", refFaceWidth))")
+    }
+}
+
+/// Thread-safe storage for active calibration thresholds
+/// Allows non-isolated code (video processing) to read thresholds without hitting MainActor
+class CalibrationState: @unchecked Sendable {
+    static let shared = CalibrationState()
+    private let queue = DispatchQueue(label: "com.gaze.calibrationState", attributes: .concurrent)
+    private var _thresholds: GazeThresholds?
+    private var _isComplete: Bool = false
+    
+    var thresholds: GazeThresholds? {
+        get { queue.sync { _thresholds } }
+        set { queue.async(flags: .barrier) { self._thresholds = newValue } }
+    }
+    
+    var isComplete: Bool {
+        get { queue.sync { _isComplete } }
+        set { queue.async(flags: .barrier) { self._isComplete = newValue } }
     }
 }

Gaze/Services/CalibrationManager.swift

@@ -56,10 +56,16 @@ class CalibrationManager: ObservableObject {
         calibrationData = CalibrationData()
     }
     
-    func collectSample(leftRatio: Double?, rightRatio: Double?) {
+    func collectSample(leftRatio: Double?, rightRatio: Double?, leftVertical: Double? = nil, rightVertical: Double? = nil, faceWidthRatio: Double? = nil) {
         guard isCalibrating, let step = currentStep else { return }
         
-        let sample = GazeSample(leftRatio: leftRatio, rightRatio: rightRatio)
+        let sample = GazeSample(
+            leftRatio: leftRatio,
+            rightRatio: rightRatio,
+            leftVerticalRatio: leftVertical,
+            rightVerticalRatio: rightVertical,
+            faceWidthRatio: faceWidthRatio
+        )
         calibrationData.addSample(sample, for: step)
         samplesCollected += 1
         
@@ -116,6 +122,10 @@ class CalibrationManager: ObservableObject {
         currentStepIndex = 0
         samplesCollected = 0
         calibrationData = CalibrationData()
+        
+        // Reset thread-safe state
+        CalibrationState.shared.isComplete = false
+        CalibrationState.shared.thresholds = nil
     }
     
     // MARK: - Persistence
@@ -157,6 +167,11 @@ class CalibrationManager: ObservableObject {
     func clearCalibration() {
         UserDefaults.standard.removeObject(forKey: userDefaultsKey)
         calibrationData = CalibrationData()
+        
+        // Reset thread-safe state
+        CalibrationState.shared.isComplete = false
+        CalibrationState.shared.thresholds = nil
+        
         print("🗑️ Calibration data cleared")
     }
     
@@ -185,19 +200,22 @@ class CalibrationManager: ObservableObject {
     
     // MARK: - Apply Calibration
     
-private func applyCalibration() {
+    private func applyCalibration() {
         guard let thresholds = calibrationData.computedThresholds else {
             print("⚠️ No thresholds to apply")
             return
         }
         
-        // Note: EyeTrackingConstants are static properties that should not be modified.
+        // Push to thread-safe state for background processing
-        // Any calibrated values should be used separately in the logic, not stored back to the constants.
+        CalibrationState.shared.thresholds = thresholds
-        // This is a placeholder for future implementation if dynamic threshold updates are needed.
+        CalibrationState.shared.isComplete = true
         
         print("✓ Applied calibrated thresholds:")
         print("  Looking left: ≥\(String(format: "%.3f", thresholds.minLeftRatio))")
         print("  Looking right: ≤\(String(format: "%.3f", thresholds.maxRightRatio))")
+        print("  Looking up: ≤\(String(format: "%.3f", thresholds.minUpRatio))")
+        print("  Looking down: ≥\(String(format: "%.3f", thresholds.maxDownRatio))")
+        print("  Screen Bounds: [\(String(format: "%.2f", thresholds.screenRightBound))..\(String(format: "%.2f", thresholds.screenLeftBound))] x [\(String(format: "%.2f", thresholds.screenTopBound))..\(String(format: "%.2f", thresholds.screenBottomBound))]")
     }
     
     // MARK: - Statistics
@@ -214,9 +232,9 @@ private func applyCalibration() {
         var summary = "Calibrated: \(dateFormatter.string(from: calibrationData.calibrationDate))\n"
         
         if let thresholds = calibrationData.computedThresholds {
-            summary += "Left threshold: \(String(format: "%.3f", thresholds.minLeftRatio))\n"
+            summary += "H-Range: \(String(format: "%.3f", thresholds.screenRightBound)) to \(String(format: "%.3f", thresholds.screenLeftBound))\n"
-            summary += "Right threshold: \(String(format: "%.3f", thresholds.maxRightRatio))\n"
+            summary += "V-Range: \(String(format: "%.3f", thresholds.screenTopBound)) to \(String(format: "%.3f", thresholds.screenBottomBound))\n"
-            summary += "Center range: \(String(format: "%.3f", thresholds.centerMin)) - \(String(format: "%.3f", thresholds.centerMax))"
+            summary += "Ref Face Width: \(String(format: "%.3f", thresholds.referenceFaceWidth))"
         }
         
         return summary

Gaze/Services/EyeTrackingService.swift

@@ -470,21 +470,68 @@ class EyeTrackingService: NSObject, ObservableObject {
             if let leftRatio = leftGazeRatio,
                 let rightRatio = rightGazeRatio
             {
+                let faceWidth = face.boundingBox.width
+                
                 Task { @MainActor in
                     if CalibrationManager.shared.isCalibrating {
                         CalibrationManager.shared.collectSample(
                             leftRatio: leftRatio,
-                            rightRatio: rightRatio
+                            rightRatio: rightRatio,
+                            leftVertical: leftVerticalRatio,
+                            rightVertical: rightVerticalRatio,
+                            faceWidthRatio: faceWidth
                         )
                     }
                 }
 
-                let avgRatio = (leftRatio + rightRatio) / 2.0
+                let avgH = (leftRatio + rightRatio) / 2.0
-                let lookingRight = avgRatio <= EyeTrackingConstants.pixelGazeMinRatio
+                // Use 0.5 as default for vertical if not available
-                let lookingLeft = avgRatio >= EyeTrackingConstants.pixelGazeMaxRatio
+                let avgV = (leftVerticalRatio != nil && rightVerticalRatio != nil)
+                    ? (leftVerticalRatio! + rightVerticalRatio!) / 2.0
+                    : 0.5
+                
+                // Use Calibrated Thresholds from thread-safe state
+                if let thresholds = CalibrationState.shared.thresholds,
+                   CalibrationState.shared.isComplete {
+                    
+                    // 1. Distance Scaling
+                    let currentFaceWidth = face.boundingBox.width
+                    let refFaceWidth = thresholds.referenceFaceWidth
+                    
+                    var distanceScale = 1.0
+                    if refFaceWidth > 0 && currentFaceWidth > 0 {
+                        distanceScale = refFaceWidth / currentFaceWidth
+                        distanceScale = 1.0 + (distanceScale - 1.0) * EyeTrackingConstants.distanceSensitivity
+                    }
+                    
+                    // 2. Normalize Gaze
+                    let centerH = (thresholds.screenLeftBound + thresholds.screenRightBound) / 2.0
+                    let centerV = (thresholds.screenTopBound + thresholds.screenBottomBound) / 2.0
+                    
+                    let deltaH = (avgH - centerH) * distanceScale
+                    let deltaV = (avgV - centerV) * distanceScale
+                    
+                    let normalizedH = centerH + deltaH
+                    let normalizedV = centerV + deltaV
+                    
+                    // 3. Boundary Check
+                    let margin = EyeTrackingConstants.boundaryForgivenessMargin
+                    
+                    let isLookingLeft = normalizedH > (thresholds.screenLeftBound + margin)
+                    let isLookingRight = normalizedH < (thresholds.screenRightBound - margin)
+                    let isLookingUp = normalizedV < (thresholds.screenTopBound - margin)
+                    let isLookingDown = normalizedV > (thresholds.screenBottomBound + margin)
+                    
+                    eyesLookingAway = isLookingLeft || isLookingRight || isLookingUp || isLookingDown
+                    
+                } else {
+                    // Fallback to default constants
+                    let lookingRight = avgH <= EyeTrackingConstants.pixelGazeMinRatio
+                    let lookingLeft = avgH >= EyeTrackingConstants.pixelGazeMaxRatio
                     eyesLookingAway = lookingRight || lookingLeft
                 }
             }
+        }
 
         result.lookingAway = poseLookingAway || eyesLookingAway
         return result
@@ -621,6 +668,8 @@ class EyeTrackingService: NSObject, ObservableObject {
         {
             var leftGazeRatio: Double? = nil
             var rightGazeRatio: Double? = nil
+            var leftVerticalRatio: Double? = nil
+            var rightVerticalRatio: Double? = nil
 
             // Detect left pupil (side = 0)
             if let leftResult = PupilDetector.detectPupil(
@@ -634,6 +683,10 @@ class EyeTrackingService: NSObject, ObservableObject {
                     pupilPosition: leftResult.pupilPosition,
                     eyeRegion: leftResult.eyeRegion
                 )
+                leftVerticalRatio = calculateVerticalRatioSync(
+                    pupilPosition: leftResult.pupilPosition,
+                    eyeRegion: leftResult.eyeRegion
+                )
             }
 
             // Detect right pupil (side = 1)
@@ -648,6 +701,10 @@ class EyeTrackingService: NSObject, ObservableObject {
                     pupilPosition: rightResult.pupilPosition,
                     eyeRegion: rightResult.eyeRegion
                 )
+                rightVerticalRatio = calculateVerticalRatioSync(
+                    pupilPosition: rightResult.pupilPosition,
+                    eyeRegion: rightResult.eyeRegion
+                )
             }
 
             // CRITICAL: Connect to CalibrationManager
@@ -655,37 +712,114 @@ class EyeTrackingService: NSObject, ObservableObject {
                 let leftRatio = leftGazeRatio,
                 let rightRatio = rightGazeRatio
             {
+                // Calculate face width ratio for distance estimation
+                let faceWidthRatio = face.boundingBox.width
+                
                 CalibrationManager.shared.collectSample(
                     leftRatio: leftRatio,
-                    rightRatio: rightRatio
+                    rightRatio: rightRatio,
+                    leftVertical: leftVerticalRatio,
+                    rightVertical: rightVerticalRatio,
+                    faceWidthRatio: faceWidthRatio
                 )
             }
 
-// Determine looking away using calibrated thresholds
+            // Determine looking away using calibrated thresholds
             if let leftRatio = leftGazeRatio, let rightRatio = rightGazeRatio {
-                 let avgRatio = (leftRatio + rightRatio) / 2.0
+                let avgH = (leftRatio + rightRatio) / 2.0
-                 let lookingRight = avgRatio <= EyeTrackingConstants.pixelGazeMinRatio
+                // Use 0.5 as default for vertical if not available (though it should be)
-                 let lookingLeft = avgRatio >= EyeTrackingConstants.pixelGazeMaxRatio
+                let avgV = (leftVerticalRatio != nil && rightVerticalRatio != nil) 
-                 eyesLookingAway = lookingRight || lookingLeft
+                    ? (leftVerticalRatio! + rightVerticalRatio!) / 2.0 
+                    : 0.5
+                
+                 // Use Calibrated Thresholds if available
+                 // Use thread-safe state instead of accessing CalibrationManager.shared (MainActor)
+                 if let thresholds = CalibrationState.shared.thresholds,
+                    CalibrationState.shared.isComplete {
+                     
+                     // 1. Distance Scaling
+                    // If current face is SMALLER than reference, user is FURTHER away.
+                    // Eyes move LESS for same screen angle. We need to SCALE UP the deviation.
+                    let currentFaceWidth = face.boundingBox.width
+                    let refFaceWidth = thresholds.referenceFaceWidth
+                    
+                    var distanceScale = 1.0
+                    if refFaceWidth > 0 && currentFaceWidth > 0 {
+                        // Simple linear scaling: scale = ref / current
+                        // e.g. Ref=0.5, Current=0.25 (further) -> Scale=2.0
+                        distanceScale = refFaceWidth / currentFaceWidth
+                        
+                        // Apply sensitivity tuning
+                        distanceScale = 1.0 + (distanceScale - 1.0) * EyeTrackingConstants.distanceSensitivity
+                    }
+                    
+                    // 2. Normalize Gaze (Center Relative)
+                    // We assume ~0.5 is center. We scale the delta from 0.5.
+                    // Note: This is an approximation. A better way uses the calibrated center.
+                    let centerH = (thresholds.screenLeftBound + thresholds.screenRightBound) / 2.0
+                    let centerV = (thresholds.screenTopBound + thresholds.screenBottomBound) / 2.0
+                    
+                    let deltaH = (avgH - centerH) * distanceScale
+                    let deltaV = (avgV - centerV) * distanceScale
+                    
+                    let normalizedH = centerH + deltaH
+                    let normalizedV = centerV + deltaV
+                    
+                    // 3. Boundary Check with Margin
+                    // "Forgiveness" expands the safe zone (screen bounds).
+                    // If you are IN the margin, you are considered ON SCREEN (Safe).
+                    // Looking Away means passing the (Bound + Margin).
+                    
+                    let margin = EyeTrackingConstants.boundaryForgivenessMargin
+                    
+                    // Check Left (Higher Ratio)
+                    // Screen Left is e.g. 0.7. Looking Left > 0.7.
+                    // To look away, must exceed (0.7 + margin).
+                    let isLookingLeft = normalizedH > (thresholds.screenLeftBound + margin)
+                    
+                    // Check Right (Lower Ratio)
+                    // Screen Right is e.g. 0.3. Looking Right < 0.3.
+                    // To look away, must be less than (0.3 - margin).
+                    let isLookingRight = normalizedH < (thresholds.screenRightBound - margin)
+                    
+                    // Check Up (Lower Ratio, usually)
+                    let isLookingUp = normalizedV < (thresholds.screenTopBound - margin)
+                    
+                    // Check Down (Higher Ratio, usually)
+                    let isLookingDown = normalizedV > (thresholds.screenBottomBound + margin)
+                    
+                    eyesLookingAway = isLookingLeft || isLookingRight || isLookingUp || isLookingDown
                     
                     if shouldLog {
-                    print(
+                        print("👁️ CALIBRATED GAZE: AvgH=\(String(format: "%.2f", avgH)) AvgV=\(String(format: "%.2f", avgV)) DistScale=\(String(format: "%.2f", distanceScale))")
-                        "👁️ PIXEL GAZE: L=\(String(format: "%.3f", leftRatio)) R=\(String(format: "%.3f", rightRatio)) Avg=\(String(format: "%.3f", avgRatio)) Away=\(eyesLookingAway)"
+                        print("   NormH=\(String(format: "%.2f", normalizedH)) NormV=\(String(format: "%.2f", normalizedV)) Away=\(eyesLookingAway)")
-                    )
+                        print("   Bounds: H[\(String(format: "%.2f", thresholds.screenRightBound))-\(String(format: "%.2f", thresholds.screenLeftBound))] V[\(String(format: "%.2f", thresholds.screenTopBound))-\(String(format: "%.2f", thresholds.screenBottomBound))]")
-                    print(
-                        "   Thresholds: Min=\(String(format: "%.3f", EyeTrackingConstants.pixelGazeMinRatio)) Max=\(String(format: "%.3f", EyeTrackingConstants.pixelGazeMaxRatio))"
-                    )
                     }
+                    
                 } else {
-                if shouldLog {
+                    // Fallback to default constants
-                    print("⚠️ Pixel pupil detection failed for one or both eyes")
+                    let lookingRight = avgH <= EyeTrackingConstants.pixelGazeMinRatio
-                }
+                    let lookingLeft = avgH >= EyeTrackingConstants.pixelGazeMaxRatio
+                    eyesLookingAway = lookingRight || lookingLeft
                 }
                 
                 // Update debug values
                 Task { @MainActor in
                     debugLeftPupilRatio = leftGazeRatio
                     debugRightPupilRatio = rightGazeRatio
+                    debugLeftVerticalRatio = leftVerticalRatio
+                    debugRightVerticalRatio = rightVerticalRatio
+                }
+
+                 if shouldLog && !CalibrationState.shared.isComplete {
+                    print(
+                        "👁️ RAW GAZE: L=\(String(format: "%.3f", leftRatio)) R=\(String(format: "%.3f", rightRatio)) Avg=\(String(format: "%.3f", avgH)) Away=\(eyesLookingAway)"
+                    )
+                 }
+            } else {
+                if shouldLog {
+                    print("⚠️ Pixel pupil detection failed for one or both eyes")
+                }
             }
         } else {
             if shouldLog {

Gaze/Services/PupilDetector.swift

@@ -747,10 +747,23 @@ final class PupilDetector: @unchecked Sendable {
         let size = width * height
         guard size > 0 else { return }
         
-        // SIMPLIFIED: Skip blur to avoid contaminating dark pupil pixels with bright mask pixels
+        // 1. Apply Gaussian Blur (reduces noise)
-        // Apply binary threshold directly to input
+        // We reuse tempBuffer for intermediate steps if available, or just output
+        // Note: gaussianBlurOptimized writes from input -> output
+        gaussianBlurOptimized(input: input, output: output, width: width, height: height)
+        
+        // 2. Apply Erosion (expands dark regions)
+        // Python: cv2.erode(kernel, iterations=3)
+        // This helps connect broken parts of the pupil
+        // Note: erodeOptimized processes in-place on output if input==output
+        erodeOptimized(input: output, output: output, width: width, height: height, iterations: 3)
+        
+        // 3. Binary Threshold
         for i in 0..<size {
-            output[i] = input[i] > UInt8(threshold) ? 255 : 0
+            // Python: cv2.threshold(..., cv2.THRESH_BINARY)
+            // Pixels > threshold become 255 (white), others 0 (black)
+            // So Pupil is BLACK (0)
+            output[i] = output[i] > UInt8(threshold) ? 255 : 0
         }
     }
 
@@ -851,47 +864,103 @@ final class PupilDetector: @unchecked Sendable {
 
     // MARK: - Optimized Contour Detection
 
-    /// Optimized centroid-of-dark-pixels approach - much faster than union-find
+    /// Finds the largest connected component of dark pixels and returns its centroid
-    /// Returns the centroid of the largest dark region
+    /// This is much more robust than averaging all dark pixels, as it ignores shadows/noise
     private nonisolated static func findPupilFromContoursOptimized(
         data: UnsafePointer<UInt8>,
         width: Int,
         height: Int
     ) -> (x: Double, y: Double)? {
+        let size = width * height
         
-        // Optimized approach: find centroid of all black pixels
+        // 1. Threshold pass: Identify all dark pixels (0)
-        // This works well for pupil detection since the pupil is the main dark blob
+        // We use a visited array to track processed pixels for flood fill
+        // Using a flat bool array for performance
+        var visited = [Bool](repeating: false, count: size)
         
-        var sumX: Int = 0
+        var maxBlobSize = 0
-        var sumY: Int = 0
+        var maxBlobSumX = 0
-        var count: Int = 0
+        var maxBlobSumY = 0
         
-        // After binary thresholding, pixels are 0 (black/pupil) or 255 (white/background)
+        // 2. Iterate through pixels to find connected components
-        // Use threshold of 128 to catch any pixels that are closer to black
-        let threshold = UInt8(128)
-
-        // Process entire image to get accurate centroid
         for y in 0..<height {
             let rowOffset = y * width
             for x in 0..<width {
-                if data[rowOffset + x] < threshold {
+                let idx = rowOffset + x
-                    sumX += x
+                
-                    sumY += y
+                // If it's a dark pixel (0) and not visited, start a flood fill
-                    count += 1
+                if data[idx] == 0 && !visited[idx] {
+                    var currentBlobSize = 0
+                    var currentBlobSumX = 0
+                    var currentBlobSumY = 0
+                    
+                    // Stack for DFS/BFS (using array as stack is fast in Swift)
+                    var stack: [Int] = [idx]
+                    visited[idx] = true
+                    
+                    while let currentIdx = stack.popLast() {
+                        let cx = currentIdx % width
+                        let cy = currentIdx / width
+                        
+                        currentBlobSize += 1
+                        currentBlobSumX += cx
+                        currentBlobSumY += cy
+                        
+                        // Check 4 neighbors
+                        // Right
+                        if cx + 1 < width {
+                            let nIdx = currentIdx + 1
+                            if data[nIdx] == 0 && !visited[nIdx] {
+                                visited[nIdx] = true
+                                stack.append(nIdx)
+                            }
+                        }
+                        // Left
+                        if cx - 1 >= 0 {
+                            let nIdx = currentIdx - 1
+                            if data[nIdx] == 0 && !visited[nIdx] {
+                                visited[nIdx] = true
+                                stack.append(nIdx)
+                            }
+                        }
+                        // Down
+                        if cy + 1 < height {
+                            let nIdx = currentIdx + width
+                            if data[nIdx] == 0 && !visited[nIdx] {
+                                visited[nIdx] = true
+                                stack.append(nIdx)
+                            }
+                        }
+                        // Up
+                        if cy - 1 >= 0 {
+                            let nIdx = currentIdx - width
+                            if data[nIdx] == 0 && !visited[nIdx] {
+                                visited[nIdx] = true
+                                stack.append(nIdx)
                             }
                         }
                     }
                     
-        if enableDiagnosticLogging && count < 5 {
+                    // Check if this is the largest blob so far
-            logDebug("👁 PupilDetector: Dark pixel count = \(count) (need >= 5)")
+                    if currentBlobSize > maxBlobSize {
+                        maxBlobSize = currentBlobSize
+                        maxBlobSumX = currentBlobSumX
+                        maxBlobSumY = currentBlobSumY
+                    }
+                }
+            }
         }
 
-        // Minimum 5 pixels for valid pupil (reduced from 10 for small eye regions)
+        if enableDiagnosticLogging && maxBlobSize < 5 {
-        guard count >= 5 else { return nil }
+            logDebug("👁 PupilDetector: Largest blob size = \(maxBlobSize) (need >= 5)")
+        }
+
+        // Minimum 5 pixels for valid pupil
+        guard maxBlobSize >= 5 else { return nil }
 
         return (
-            x: Double(sumX) / Double(count),
+            x: Double(maxBlobSumX) / Double(maxBlobSize),
-            y: Double(sumY) / Double(count)
+            y: Double(maxBlobSumY) / Double(maxBlobSize)
         )
     }