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Thu 6 Oct, 2005 07:54 pm
I thought this problem would be easy...but it's turning out to be very difficult for me simply because I cannot seem to draw an accurate diagram for which to apply soh cah toa!
The problem:
Natural language: I have a vector with a known starting and ending position. I have another point in 3d space, and I know that the distance from this point to the starting point of the vector is the same as the length of the vector. Thus, the vector could be rotated so that it's endpoint lies at this other point without changing the length of the vector.
I need to find the X,Y,Z euler rotation values that will cause this vector to be rotated in the specified way. The center of rotation is the center of mass of the vector.
Then it sounds live the vector is going to be rotated around its center of mass. Assuming that the center of mass is in the middle of the vector, the distance between the vector endpoint and that point in space is half the length of the vector. If not, the vector endpoint is no more than halfway to that point in space.
But then I'm only a marginally intelligent monkey and I'm probably wrong.
Rap
I don't think you could do that if the starting point is length d from a vector of length d and you're rotating the vector about its "centre of mass" (define this term - is it the midpoint of the vector - cause if it is you can't do what you want.
Imagine a line 10cm in length 10cm from a point - facing directly away from it - unless you rotate it by its starting point - or some pint in space not on the vector you're not going to get what you desire.
You guys are right, I meant to say that the rotation point is the beginning point of the vector.
edit -- ive found a more efficient solution
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