Apply Motion

After extracting animation from a video, the next crucial step is applying this motion to your 3D model in the Scene. This process, known as retargeting, maps the extracted animation data onto your model's skeleton. Plask offers advanced features to ensure your animations look natural and professional.

Applying Motion: Step-by-Step

Method: Drag and Drop

1. 1. Locate your extracted animation in the Asset panel.
2. 2. Click and drag the animation onto the desired bone in your 3D model.
3. 3. Plask will automatically attempt to map the animation based on bone names and hierarchy.

Troubleshooting: Renaming Bones

If the automatic mapping doesn't produce the desired results, you may need to rename some bones in your model to match Plask's naming convention.

1. 1. In the Outliner, right-click on the bone you want to rename.
2. 2. Select 'Rename' from the context menu.
3. 3. Enter the new name, matching one of the standard bone names used by Plask (listed in the "Bone Structure" section below).

Advanced Feature: Stable AI and Foot End Effector Matching

Understanding End Effectors and Foot Sliding

In animation, an end effector is the part of a limb that interacts with the environment. For a human-like character, feet are crucial end effectors. A common issue in 3D animation is "foot sliding," where feet appear to slide across the ground instead of planting firmly, breaking the realism of the animation.

How Stable AI Improves Foot Placement

Plask's Stable AI introduces precise foot end effector position matching, significantly enhancing the quality of your animations:

1. 1. Accurate Foot Tracking: The AI precisely tracks foot positions in the source video.
2. 2. Intelligent Mapping: When applying motion, it ensures foot positions in your 3D model match the tracked data.
3. 3. Ground Contact Detection: The system identifies when a foot should be in contact with the ground.
4. 4. Position Locking: During ground contact phases, the foot position is locked, preventing sliding.

Benefits for All Users

• For Beginners: Achieve more natural-looking animations without manual fixes.
• For Professionals: Save time on manual corrections, focusing more on creative aspects.

Using Stable AI for Better Foot Placement

1. 1. When extracting motion from your video, select the Stable option.
2. 2. Ensure your source video has clear visibility of the feet.
3. 3. After applying the animation, play it back to observe improved foot-ground interaction.
4. 4. Minor manual adjustments can still be made if needed.

Technical Deep Dive: Mapping Rules and Bone Structure

Animation Data Structure

• Plask's motion capture system is based on a standard T-pose model.
• The system recognizes up to 52 distinct bones for a comprehensive skeletal structure.

Retargeting Process

• The retargeting system maps animation data based on bone names and hierarchical structure.
• This process allows for flexibility in model structure while maintaining accurate motion transfer.

Standard Bone Naming Convention

Plask uses a 52-bone system for comprehensive animation mapping. Here's the full list of recognized bone names:

1. 1. hips
2. 2. spine
3. 3. leftUpLeg
4. 4. rightUpLeg
5. 5. spine1
6. 6. leftLeg
7. 7. rightLeg
8. 8. spine2
9. 9. leftFoot
10. 10. rightFoot
11. 11. neck
12. 12. leftToeBase
13. 13. rightToeBase
14. 14. head
15. 15. leftShoulder
16. 16. rightShoulder
17. 17. leftArm
18. 18. rightArm
19. 19. leftForeArm
20. 20. rightForeArm
21. 21. leftHand
22. 22. rightHand
23. 23. leftHandIndex1
24. 24. rightHandIndex1
25. 25. leftHandIndex2
26. 26. rightHandIndex2
27. 27. leftHandIndex3
28. 28. rightHandIndex3
29. 29. leftHandMiddle1
30. 30. rightHandMiddle1
31. 31. leftHandMiddle2
32. 32. rightHandMiddle2
33. 33. leftHandMiddle3
34. 34. rightHandMiddle3
35. 35. leftHandRing1
36. 36. rightHandRing1
37. 37. leftHandRing2
38. 38. rightHandRing2
39. 39. leftHandRing3
40. 40. rightHandRing3
41. 41. leftHandPinky1
42. 42. rightHandPinky1
43. 43. leftHandPinky2
44. 44. rightHandPinky2
45. 45. leftHandPinky3
46. 46. rightHandPinky3
47. 47. leftHandThumb1
48. 48. rightHandThumb1
49. 49. leftHandThumb2
50. 50. rightHandThumb2
51. 51. leftHandThumb3
52. 52. rightHandThumb3

Advanced Features: Auto Transformation

During the application process, Plask performs two key automatic transformations:

1. Rotation Transform

• Adjusts bone rotations to match the source animation, regardless of initial orientation.

2. Position Scaling

• Scales position changes proportionally, adapting animations to models with different proportions.

These auto-transformations work behind the scenes to provide a seamless retargeting experience.

Best Practices and Tips

1. 1. Start with a T-pose model for optimal results.
2. 2. Use clear, well-lit video footage with the entire body visible for best motion capture.
3. 3. For walking or running animations, capture footage on a flat, consistent surface.
4. 4. When renaming bones, focus on the main skeletal structure first (hips, spine, limbs).
5. 5. Double-check your bone hierarchy in the Outliner if you encounter mapping issues.
6. 6. Remember, while V2 AI significantly improves foot placement, other parts of the body may still require manual adjustments for perfect results.

Conclusion

Understanding the intricacies of motion application in Plask, especially the advanced V2 AI foot placement feature, empowers you to create more accurate and expressive animations. By leveraging these tools and following best practices, you can efficiently transfer complex motions to your 3D models, bringing your characters to life with enhanced realism and reduced need for manual corrections.