Adding parameters to function definition avoids allocations

[jipolanco]

@user664303

struct Transform{T<:Number}
    rot::SMatrix{3, 3, T}
    trans::SVector{3, T}
end

The problem is that SMatrix{3, 3, T} is not concrete, since it is missing its fourth parameter L which is the total length of the array. Replace it with SMatrix{3, 3, T, 9} and the issue should be gone.