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* leg (yellow) keeps its length also
 
* leg (yellow) keeps its length also
 
* distance between the target and the origin of the upper leg can be easily computed in world space.
 
* distance between the target and the origin of the upper leg can be easily computed in world space.
 +
 +
Rendering the position of the knee is crucial to compute the rotation to apply on the upper leg. Once correct, the rotation of the leg will be simple to render, as it is the rotation from the current direction to the [knee - target] direction.
  
 
== References ==
 
== References ==

Revision as of 13:55, 19 April 2018

Notes about computation of inverse kinematics[1]

Solving-ik-001.png

At this moment, the research is focusing on solving a 2 bones system, the leg in this case, but it would be applicable on the arms or any other part of a skeleton having at least 2 parents.

The main issue seems to be the computation of the knee position. All distances are easily computed:

  • upper leg (red) keeps its length
  • leg (yellow) keeps its length also
  • distance between the target and the origin of the upper leg can be easily computed in world space.

Rendering the position of the knee is crucial to compute the rotation to apply on the upper leg. Once correct, the rotation of the leg will be simple to render, as it is the rotation from the current direction to the [knee - target] direction.

References

  1. Inverse kinematics sur wikipedia

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