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Quiz

  1. why global lighting model takes more time?

    Yes, a lot more. Those amazing real-time graphics for your video games are primarily local lighting. The really nice stuff you see in the movies is based on off-line rendering. Computing power continues to go up, but so does demand.

  2. How do efficient ray-tracing algorithms trace light rays from the eye into the scene?

    Here's a decent explanation of ray tracing. We start with a large but finite number of rays, from the COP to the million or so pixels, and then out into the scene...

  3. Because of the linear attenuation is there any problem in expressing real situations in the digital world?

    No, the linear attenuation is intended to simulate the fact that nearby lights are brighter than farther lights. But there certainly is a lot of tuning and trial and error to get it right. Look at the credits in an animated movie: there's always a staff of people for "lighting".