Re: [fxtf-drafts] [geometry] What is the w (perspective) value for?

Calling `w` "the perspective" is very confusing, though. As far as I can see, `w` is just a regular coordinate in ℝ<sup>4</sup> and DOMPoints are just four-component vectors (I could store RGBA values in them, if I wanted).  And they should be labelled as such - something like:

> The x, y, z and w coordinates represent an arbitrary point in a four-dimensional space. By convention, they are treated as a homogeneous representation of points in ℙℝ<sup>3</sup> with the Euclidean space embedded at w=1, and the x, y and z coordinates giving the normal three-dimensional position.

AKA It's awfully convenient to do 3D maths in 4D with the fourth coordinate set to 1.

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Received on Friday, 1 June 2018 14:10:22 UTC