Question: Why do we set last row of affine camera matrix to [0 0 0 1]?

patrikhuber / eos

A lightweight 3D Morphable Face Model library in modern C++

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Question: Why do we set last row of affine camera matrix to [0 0 0 1]? #314

Closed ShrivastavaKartik closed 4 years ago

ShrivastavaKartik commented 4 years ago

Hi, I've a small doubt in the last part of fitting::get_3x4_affine_camera_matrix(RenderingParameters params, int width, int height). What's the reason behind ignoring the data in last row of full_projection_3x4 by setting it to [0 0 0 1]? Doesn't it contains the rotation along x, y with scale along z-axis? Edit: Maybe this question is more of what happens after viewport transformation, so any info regarding that would be much appreciated.

ShrivastavaKartik commented 4 years ago

I got that, just reviewed a transformation lesson.