An example of how raytracing can be done on old DOS computers. Compileable with either Borland Turbo C++ 3.1 or Open Watcom. Requires DOSBox or a real DOS computer.
Extra command line flags:
-f XX - set fov to XX (default: 45 degrees)
-g - render in grayscale (fast, 16 shades of default VGA palette)
-gp - render in grayscale using full 256 shades of gray
-vga - use standard VGA palette (uglier and slower!)
-d - enable dithering