MinimalTicTacToe
Derivation of a minimal size tree for playing perfect tic tac toe
Read more →Chris Lomont's Posts Page
Correct alpha and gamma for image processing
This is a note on the correct usage of alpha blending, pre-multiplied alpha, gamma correction, and linear colors for image processing.
Read more →IOS PNG Errors
XCode corrupts PNG images for iOS builds. This post details the error.
Read more →Problems using SSIM for image quality comparisons
Variation among SSIM implementations make comparing results a mess. This version matches the output of the original, unlike most of those in common use as of 2023.
Read more →Accurate color conversions
This is a quick note for converting byte values colors in 0-255 back and forth to floating-point colors in 0-1 which avoids common errors.
Read more →Button debouncing and pattern matching
A robust, portable, extensible method for handling button presses when interfacing software and hardware.
Read more →A better quadratic formula algorithm
A robust algorithm for computing roots of quadratic equations, much better than common code.
Read more →Lomont floating point notes
Notes on floating point issues, including lists of facts and theorems useful for algorithm development.
Read more →Rtk Gps Project
I built a RTK-GPS gadget and wrote enough software to do basic GNS tasks such as finding distances, decoding GPS NMEA and RTCM messages, finding intersections, and doing boundary detection.
Read more →Chris Lomont's lines of code over time
Over decades I’ve written a lot of personal code. I made a bar chart race showing how many lines I’ve written in different languages over time.
Read more →New C# syntax and features
Here’s a brief summary of C# features by version.
Read more →Walking Ant Probability Problem
Here’s a math puzzle.
Read more →A Universal FRACTRAN Interpreter in FRACTRAN
Here’s FRACTRAN, a weird fraction based programming language, written in FRACTRAN.
Read more →Generating Uniform Random Numbers on [0,1]
How does one generate uniform random numbers in [0,1] using IEEE 754 floating point formats? It’s tricky.
Read more →Efficient divisibility testing
Here’s bit tricks for efficient divisibility testing.
Read more →Making Three NOT Gates from Two
This is a hard puzzle about using two NOT gates to build three.
Read more →Compression Notes
Here’s some notes on compression.
Read more →LZCL: An embedded compression library
Here’s an embedded compression format I designed to meet certain requirements. It’s small, fast, and efficient.
Read more →Average segment length
What’s the average length of a segment chosen uniformly by area on a unit square?
Read more →How many prisoners?
This is a nicely hard problem in the common prisoners and warden format.
Read more →Pick a Number
Here’s a result that is completely non-intuitive.
Read more →Test site features
A post to test site features such as tables, math, code…
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