Consider different Multidimensional Arrays Implementations

[Skylion007]

So after looking through the optimizations of this library, we are more or less at a local minimum when it comes to our naive representation of multidimensional arrays. They are currently untyped and simply use the classic Array of Array implementation. We should consider ways of storing our arrays in alternative ways and possibly typing them to get better performance. There is a case to be made that we might want to implement something similar to NDArray, but doing so it contingent on issue #35 . LU decomposition still takes up a rather large portion of the run time.

Currently here are three areas of optimization to focus on:

1. track() inside of CLMR tracker
2. getPupilFeatures()
3. LUDecomposition() and the entire ridge methods

Optimizing these areas will be important if we want to make it practical to run on mobile.

Some reading on the topic: https://0fps.net/2013/05/22/implementing-multidimensional-arrays-in-javascript/ https://github.com/mikolalysenko/ndarray-experiments

[sneha-belkhale]

Hey , I was thinking about helping out on this issue ( I really like this project and was planning to use it for a little web experience ) .

It looks like the functions you mentioned are outside the WebGazer repo? It looks like you are using LUDecomposition from the numeric.js library, and tracking is from the clmtracker repo?

[jeffhuang]

That's correct @sneha-belkhale . Those can be optimized separately, or specifically for WebGazer. Would love to see what you come up with.

[jeffhuang]

note that we're not using clmtrackr anymore so the first area is not as impactful

[Skylion007]

Something in WASM like Eigen-JS may be a good candidate for CPU implementations: https://github.com/BertrandBev/eigen-js