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Don't Disturb
02-14-2002, 06:55 AM
Given two sets of 4 non-coplanar points, how do I find the matrix to project from one set to the other?
Thanks.

Coconut
02-14-2002, 07:34 AM
Originally posted by Don't Disturb:
Given two sets of 4 non-coplanar points, how do I find the matrix to project from one set to the other?
Thanks.

Suppose you have (x1, y1, z1),..(x4, y4, z4)
and (x'1, y'1, z'1),..(x'4, y'4, z'4).
Create 2 matrices:

M =
x1 x2 x3 x4
y1 y2 y3 y4
z1 z2 z3 z4
1 1 1 1

M' =
x'1 x'2 x'3 x'4
y'1 y'2 y'3 y'4
z'1 z'2 z'3 z'4
1 1 1 1

The transformation T you may be looking for would be:

T * M = M'
T = M' * M^-1

Don't Disturb
02-14-2002, 08:05 AM
Thankyou very much.