Re: [csswg-drafts] [css-transforms] Inconsistencies in 2D and 3D matrix decomposition (#3713)

I've been working through this trying to fix inconsistencies in Gecko but I'm having trouble understanding how this produces consistent results for 2D/3D for input such as `matrix(1, 0, 0, -1, 0, 0)`.

As far as I can tell, the 3D decomposition would yield a quaternion of `0, 1, 0, 0` and debugging Gecko and Chrome I see they both give that.

However, using the algorithm above we have:
> decomp3d.quaternion = [0, 0, sin(decomp2d.angle/2), cos(decomp2d.angle/2)]

Which is clearly never going to give `0, 1, 0, 0`.

Instead, applying the above logic in Gecko I get `0, 0, 0, 1`.

@kevers-google Is there something I'm missing here?

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Received on Friday, 24 May 2019 04:35:44 UTC