https://www.jsweet.org/examples/#Ray_tracer
Written in Java then transpiled to JavaScript, been around for years.
Written in Java then transpiled to JavaScript, been around for years.
Your link appears to be a basic ray tracer which anyone who has taken an intro to computer graphics course in college is likely required to implement and would only need a javascript canvas. To be honest I have no idea how much OPs real-time ray tracing differs in complexity from traditional ray tracing.
You could simulate pixels with divs if that's all you had. Or you could create an image in memory and save to file. You could write the text for it and save as SVG.
For a CPU based ray tracer, you don't need any output capability at all(unless you want it to be interactive, which school assignment raytracers usually don't have to).