antonyakushin
commented
1 year ago The size of the dots setting makes the diameter of the dots a simple percentage of the screen size (the lesser of the screen width and height). So if your screen is 1000 pixels by 750 pixels, and you make the dot size 10, their diameter will be 75 pixels, which is 10% of 750 pixels, which is the lesser of the 1000 pixel width and 750 pixel height. By the way, you can also see what each setting does by clicking the "(?)" next to the setting name, when available.
For Snellen acuity you'll need to factor in your monitor's display size, screen resolution, and DPI to extrapolate an accurate percentage to use. You may also want to look at the source code at https://github.com/antonyakushin/okn-dots-visualization/blob/master/js/main.js#L704 to see how I use angle rounding to animate more smoothly so it doesn't hurt the eye to look at the rotating dots, though this should not have impact on dot size except that they may be rendered as fractional pixels which may appear blurry around the edges in specific frames.
Hello, I am an optometry student at the University of Houston College of Optometry. I am currently conducting research on OKN and I have been utilizing this web application. I have a question regarding the size of the dots. Is there a specific equation you used to determine the dot size? What is the difference between a dot of size "1" vs. size "2?" We are trying to determine a Snellen acuity based on the dot sizes, and may present this as a stimulus to infants.
Thank you!