Normal Vector from Matrix

[markraz]

Hi If I have matrix that looks like this picture




is the normal vector the diagonal?

 

[Dr.Peterson]

Normal to what?

Is there any context to your question, such as what the matrix represents?

 

[markraz]

Normal to what?

Is there any context to your question, such as what the matrix represents?

Thanks, The matrix is a perspective projection matrix.

10.2. Perspective Projection Model — Machine Vision Study Guide

I'm wondering if that diagonal represents the normal to the "view plane" (the yellow grid)

Thanks

 

[Mr. Bland]

Is there any context to your question, such as what the matrix represents?

It's the standard perspective projection matrix for converting view coordinates into device coordinates in 3D imaging. It is multiplied by a four-element vector representing the view coordinates (X, Y, Z, W) and produces a four-element vector in homogeneous device coordinates.

I'm wondering if that diagonal represents the normal to the "view plane" (the yellow grid)

The formula was designed in such a way that the X and Y coordinates (after performing the perspective divide) indicate the relative position in the viewport (before scaling to the viewport dimensions). All positions for Z are parallel and do not affect the position of the point in the viewport.