Maybe it's my memory from 20 years ago playing tricks on me, but to quote Civvie 11: "It's like playing a version of [Extreme Tux Racer] where everything was moved two inches or so to the left."
I also played it back in the day and it seems perfectly accurate to me, at least in terms of control and physics. After a few goes I'm quickly approaching my old personal best on Who Says Penguins Can't Fly. One thing I'll note is that the "best score" display seems to be only based on time, not herrings (which I actually prefer, but I know that's not how you're supposed to play it).
This was always a victory to teenage me after fighting with SDL and Nvidia drivers on Gentoo. Getting this to work with good framerate was always so exciting. Nostalgia hit for sure.
Funny, I've loaded it in the browser, played it, was happy like kid.
Then I just entered 'extremtuxracer' in my terminal and tada, played it locally without browser. Not to blame tuxracer.js, this is great. But sometimes you forget "normal" software.
the browser version doesn't work for me, the maps are messed up. anyways i did the same. except i had to install it first, because this is a relatively new laptop. i did have it on the previous one and almost every machine of mine before that.
i even made my own courses. one thing that i'd like to change is the slope. i made one course that would start in the center and then go in concentric circles around the starting point. it worked, kind of, but it was tricky. it would have worked better with a slope of 0 and a greater height differential from the highest to the lowest level. maybe some day...
I tried doing this a few years ago, mapping OpenGL 1.x primitives into WebGL was indeed a pain. There were some translation layers but they were either incomplete or targetting GLES, not classical OoenGL.
I then attempted to actually rewrite ETR to use GLES (or modern OpenGL in general), but that also turned out to be quite an effort given how the original engine/game code is structured.
Oh, fantastic! I've tried rebuilding this for macOS half a dozen times, and never quite managed for one reason or another. And now you've brought it to the browser.
I might try adding reflections and translucency to ice someday.
If you want to play locally on macOS, here is a build. If it fails to run, it is likely the error "The requested video mode is not available" and can be run if connected to an external monitor (then you can disable fullscreen and launch without an external monitor).
It could be a webpage but the developer would have to host it on a server somewhere (which would cost something). With the instructions to run it on the GitHub page, you are effectively running a server which is hosting the game.
If you want to play locally on macOS, here is a build. If it fails to run, it is likely the error "The requested video mode is not available" and can be run if connected to an external monitor (then you can disable fullscreen and launch without an external monitor).
This guy ports open source games to mobile devices and sells them under their original names. (Selling is okay, misrepresenting them as the official version is not.)
https://play.neverball.org/