[vtkusers] projections and transformations

[Giancarlo Amati]

Good morning Guys,

this is my question:

I have a dataset, and a projection matrix resulting from a calibration process. now:

the projection matrix P = 3x4 matrix. While transformation in VTK are 4x4 matrices.
So, I transformed my P in a 4x4 by inserting a NULL row inbetween the 2nd and the 3rd row. this makes  the Z null.

Now If I put this final P into a vtkTransform object and apply to my polydata, are the coordinates in the politdata divided automatically by that famous homogeneous coordinate factor W?

let's say that PD is my PolyData and I want to visualized the 2D by multiply P * PD where of course I get coordinate like (Xi,Yi, 0, Wi). But now I would like Xi/Wi which is a homogeneous normalization.... is it that automatic or I have to make it expiciltly?

Very kind regards.
Giancarlo 
 		 	   		  
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