I didn't follow this bit (from Part 2): "This requires a bit more geometry. Recall from last time that we detect an intersection by constructing a right triang

I didn't follow this bit (from Part 2): "This requires a bit more geometry. Recall from last time that we detect an intersection by constructing a right triangle between the camera origin and the center of the sphere. We can calculate the distance between the center of the sphere and the camera, and the distance between the camera and the right angle of our triangle. From there, we can use Pythagoras’ Theorem to calculate the length of the opposite side of the triangle. If the length is greater than the radius of the sphere, there is no intersection." The two sides he describes have the camera in common - so the "opposite" side of that triangle is the line from the center of the sphere to the right angle - I don't see how this helps.... Edit: ok I finally get it but I think he should just label some of these lengths on the diagram with letters (a,b,c etc) and then just show how they are related by stating Pythagoras theorem explicitly...