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### #Actualcr88192

Posted 15 May 2013 - 01:35 PM

FWIW: one trick I had used before for interpolating matrices directly was to identify a common rotation axis, and then rotate all of the vectors in the matrix (as points) along this axis.

typically this axis was found/approximated by finding which unit axis changed the least during the movement, interpolating this axis (by treating it as an arc along the plane formed by its 2 positions and the origin), and then using this interpolated axis to rotate the matrix by (trying to rotate the source-matrix into the destination matrix).

(there may be better ways to calculate this axis though).

the math gets hairy, and there may be a better and more accurate ways to do this, but in my uses it seemed to work ok (much better than linearly interpolating them at least...).

(I can imaging a few ugly hacks though to possibly boost accuracy, but decided against elaborating on them).

### #2cr88192

Posted 15 May 2013 - 01:35 PM

FWIW: one trick I had used before for interpolating matrices directly was to identify a common rotation axis, and then rotate all of the vectors in the matrix (as points) along this axis.

typically this axis was found/approximated by finding which unit axis changed the least during the movement, interpolating this axis (by treating it as an arc along the plane formed by its 2 positions and the origin), and then using this interpolated axis to rotate the matrix by (trying to rotate the source-matrix into the destination matrix).

(there may be better ways to calculate this axis though).

the math gets hairy, and there may be a better and more accurate ways to do this, but in my uses it seemed to work ok (much better than linearly interpolating them at least...).

(I can imaging a few ugly hacks though to possibly boost accuracy, but decided against elaborating on them).

### #1cr88192

Posted 15 May 2013 - 01:12 PM

FWIW: one trick I had used before for interpolating matrices directly was to identify a common rotation axis, and then rotate all of the vectors in the matrix (as points) along this axis.

typically this axis was found/approximated by finding which unit axis changed the least during the movement, interpolating this axis (by treating it as an arc along the plane formed by its 2 positions and the origin), and then using this interpolated axis to rotate the matrix by (trying to rotate the source-matrix into the destination matrix).

the math gets hairy, and there may be a better and more accurate ways to do this, but in my uses it seemed to work ok (much better than linearly interpolating them at least...).

(I can imaging a few ugly hacks though to possibly boost accuracy, but decided against elaborating on them).

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