glquake.exe in a window on the Windows desktop: WGL and Win32 answered in JavaScript, OpenGL drawn by WebGL.
GLQuake (Win32) runs on PRISM, a C and C++ compiler written in plain JavaScript. ★ Star it on GitHub if you liked seeing it here.
Arguments
+host_framerate 0.0138 keeps the world at real speed; try +map e1m1. **On the Windows machine add `+_windowed_mouse 1`**: vid_win.c:1610 activates the mouse in a WINDOWED mode only if that cvar is set, because on a real desktop a windowed game leaves the pointer to the desktop. On DOS and X11 the mouse needs nothing.
They go in this page's address, so a link to it starts the program the same way.
PRISM's log
What PRISM says while it runs the program shows here once it is playing.
Needs id1/pak0.pak and pak1.pak from your copy: the page asks for your copy, a folder or a .zip, and reads it where it is; nothing is uploaded.
It needs a keyboard, and most games take the mouse too.