If you're seeing this message, it means we're having trouble loading external resources on our website.

If you're behind a web filter, please make sure that the domains *.kastatic.org and *.kasandbox.org are unblocked.

Main content

Ray tracing

Problem

In the interactive below you can select a ray by clicking on the grid on the left. You can rotate the house by clicking and dragging on the right half of the window.
Select a ray that hits the house and creates a green pixel.