pub fn recompose(theta: f32, phi: f32, sx: f32, sy: f32) -> (f32, f32, f32, f32)Expand description
The inverse of decompose — R(θ)·diag(sx, sy)·R(φ), multiplied out.
The one place the SVD becomes a matrix again, and the only arithmetic on
the path from a preset’s levers to the GPU. Everything upstream of it works
on (θ, φ, sx, sy), where safety is a comparison.