Comment Japanese funding agencies (Score -1) 262
Japanese funding agencies would maybe have something else to do with their money in the next ten years, sadly ?
This is raycasting, not raytracing.
When doing raycasting, you will basically throw one ray per column (320x240 resolution -> 320 rays) (only primary rays are thrown, most of the time). Perspective is then added (the farest the ray hits, the smallest the wall will be on the screen). Quite fast, albeit very simple (no lighting, reflexion, or such).
When doing raytracing, you throw one ray per pixel (that's the primary one) to know which object it hits, then another one for each light source (secondary one, for shadows and color), then N others if needed (think reflection, etc.). Each of these secondary rays will then throw other rays, etc etc. Computationally very intensive, even after good optimizations, but quite realistic.
Adding features does not necessarily increase functionality -- it just makes the manuals thicker.