[eigen] More efficient way to transform 3D coordinates to 2D.
• To: eigen@xxxxxxxxxxxxxxxxxxx
• Subject: [eigen] More efficient way to transform 3D coordinates to 2D.
• From: Billy Araujo <billyaraujo@xxxxxxxxx>
• Date: Fri, 11 May 2012 15:38:39 +0100
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```I was thinking of implementing 3D to 2D transformation in the following way:

If I have 3 vertices, calculate v1, v2 vectors. Calculate cross
product of v1, v2 to get vz.
Then calculate vy using v1 and vz. vx = v1.

Then build a matrix with [vx, vy, vz] and multiply each vertex to get
local coordinates. The idea is to get 0 in z-coordinate.

Is there a better a better way to do this? Since I don't know anything