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## Pixar in a Box

### Course: Pixar in a Box>Unit 15

Lesson 1: Rendering 101

# 3. Light rays

Let's look more closely at how light bounces when it strikes an object. We'll cover reflected and refracted rays, direct and indirect illumination, and shadow rays. Refracted rays follow the path light takes when it passes through a transparent object, like a glass of water. Reflected rays follow the path light takes when it bounces off a shiny surface. Click here for more detail on refraction!

## Want to join the conversation?

• I couldn't get the interactives on the two previous exercises to work. On the ray tracing exercise, a large part of the interactive would disappear, and on the Matching properties of lighting exercise, the interactive would just freeze up on me, making it unusable. I have tried reloading the pages multiple times, but I get the same result. Is this just me, or is it a problem with the site itself?
• If you have multiple tabs open, try closing them. If the problem continues, reboot your computer.
• would it be indirect illumination if you had an i-pad and the light coming from it was hitting you?
• No, that would be directly lighting since the light is coming directly from the source (the iPad) to you. Indirect lighting would be if you have a spotlight pointing at a wall, and the light reflected off the wall lights your face.
• What is the difference between reflected and refracted rays?
• A reflected ray bounces off an object and a refracted ray passes through an object
• On the previous interactive, the controls were in Spanish, is this just me or is everyone experiencing this?
• On the ray tracing exercise, it randomly turned to Spanish halfway through. I CAN"T READ SPANISH? Also, stuff was randomly disappearing every now and then.
• why is every thing 6 or 5 years ogo
• Does everything have reflected rays