Add skeleton spritekit

[asabri97]

🛠️ PR Summary

_{Made with ❤️ by Ultralytics Actions}

🌟 Summary

Adds a new real-time, articulated “X-ray” skeleton visualization for pose results using SpriteKit, plus external display and model-loading reliability improvements. 🦴✨

📊 Key Changes

• New skeleton rendering system
  • Introduces SkeletonUtilities (geometry, effects, texture loading) and SkeletonMask protocol.
  • Adds ArticulatedSkeletonMask to assemble body parts (head, torso, arms, legs, feet) from assets and pose keypoints.
  • Visual effects: vignette, tint-based X-ray look, pulsing alpha animation.
  • Converts normalized keypoints to SpriteKit coordinates and scales/rotates parts per bone angles.
• PoseEstimator updates
  • New properties: useRealisticSkeleton (toggle), skeletonConfThreshold, skeletonType.
  • New methods to render skeleton overlays on CIImage/UIImage and live view.
• YOLOView integration
  • Adds a transparent SKView overlay (skeletonView) for real-time skeleton scenes in Pose task.
  • Proper setup/teardown across mode switches and layout updates.
• ViewController improvements
  • Automatically enables articulated skeleton mode for Pose models.
  • Main-thread safety and cleaner model-loading flow; improved external display coordination.
• External display robustness
  • Adds hasExternalDisplay supporting iOS 16+ APIs with graceful fallback.
  • Safer logs and notification handling during model switches.
• Assets added
  • Body part images for head, torso, pelvis, arms, forearms, hands, thighs, shins, feet (left/right).
• Misc
  • Build version bumped (534 → 574).
  • Minor cleanups (removed unused var, tidied logs, small Plot cleanup).

🎯 Purpose & Impact

• More engaging pose viz: Users get a visually rich, articulated “X-ray” skeleton that aligns to detected joints in real time. 🕺
• Clarity and confidence control: Bones are shown based on keypoint confidence, reducing jitter/noise.
• Better UX: Smooth SpriteKit overlay with subtle effects improves the app’s visual polish.
• Developer flexibility: Simple toggle via PoseEstimator.useRealisticSkeleton and adjustable skeletonConfThreshold.
• Stability with external displays: More reliable detection of screens and consistent model update behavior.
• Backward compatible: Default behavior falls back to standard pose drawing unless skeleton mode is enabled, minimizing risk for existing flows.

[UltralyticsAssistant]

👋 Hello @asabri97, thank you for submitting a ultralytics/yolo-ios-app 🚀 PR! This is an automated message; an engineer will review and assist shortly. To ensure a seamless integration of your work, please review the following checklist:

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[UltralyticsAssistant]

🔍 PR Review

_{Made with ❤️ by Ultralytics Actions}

The SpriteKit overlay looks great, but right now those two call sites rebuild the entire mask — and reload every texture — on each frame/inference. Reusing a single ArticulatedSkeletonMask (or its textures) will prevent the skeleton overlay from becoming the dominant performance cost.

💬 Posted 2 inline comments

📋 Skipped 15 files (lock files, minified, images, etc.)

[UltralyticsAssistant]

⚠️ HIGH: ArticulatedSkeletonMask() is recreated for every frame. Each initializer reloads all 15 textures from disk, so this path will be hit dozens of times per second and will quickly become the hottest point in the render loop. Please cache a single mask (or at least its textures) and reuse it instead of instantiating a new one here.

[UltralyticsAssistant]

⚠️ HIGH: ArticulatedSkeletonMask() is constructed on every inference pass (also in createRealisticSkeletonImage). The initializer reloads every texture from the asset catalog, so running pose on live video will thrash the main thread and I/O. Please cache one mask instance (or share its textures) on the estimator and reuse it across calls.

[codecov]

Codecov Report

❌ Patch coverage is 0% with 472 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
Sources/YOLO/ArticulatedSkeletonMask.swift	0.00%	283 Missing ⚠️
Sources/YOLO/PoseEstimator.swift	0.00%	83 Missing ⚠️
Sources/YOLO/0SkeletonUtilities.swift	0.00%	67 Missing ⚠️
Sources/YOLO/YOLOView.swift	0.00%	39 Missing ⚠️

📢 Thoughts on this report? Let us know!