17:T4fd,Converting that integer to a Year, Month and Day is a fundamental calculation made in almost all programming languages and standard libraries. It runs every time a date is displayed, whether it's in a user interface, log, API etc.

While it is rarely a bottleneck, it is a very frequently run algorithm, and thus has attracted a lot of attention over the years.

In 2021, Cassio Neri and Lorenz Schneider developed the Neri-Schneider algorithm, which was a major breakthrough in this niche area.

Lately, I have been studying this function deeply, and found what I believe may be the last remaining substantial improvements achievable on current hardware. The gains come mainly from counting dates backwards, and from reducing the number of multiplications from 7 to 4.

Adoption will depend on whether library maintainers consider the performance benefit to outweigh the readability. If this is rejected on readability grounds, then in those cases my algorithm outlined in Article 1 (linked in the blog post navigation) is likely to be simpler and faster than what almost all existing libraries are currently doing.

I found this a very interesting challenge to work on, and I believe some of the techniques outlined may be applicable to other areas of optimisation.18:T533,Description:

I've developed a display calibration system that makes premium HUD (Head-Up Display) technology affordable by replacing expensive waveguide optics with calibrated LCD films.

The Breakthrough:

0.015px RMS accuracy using phone cameras

9-second calibration process

Eliminates $50,000+ professional calibration equipment

Makes $5 LCD films perform like $200 waveguide optics

How It Works: Traditional HUDs require complex waveguide optics costing $80-200 per unit. My technology enables cheap LCD films to achieve the same optical quality through subpixel-perfect calibration. The system uses phase-shift algorithms to measure and compensate for display imperfections, windshield curvature, and subpixel misalignment.

Technic

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