Is it possible to make a shape that passes through light so you can see through it with the light bent due to refraction? Like a lens or a glass (or water)?
Yes, everything is possible with the amazing power of Physics! You'll need to create your own shader though. From Wikipedia:
In the field of computer graphics, a shader is a computer program that is used to do shading: the production of appropriate levels of color within an image, or, in the modern era, also to produce special effects or do video post-processing. A definition in layman's terms might be given as "a program that tells a computer how to draw something in a specific and unique way".
objc.io has a great tutorial on SceneKit if you're interested.
来源：https://stackoverflow.com/questions/31276054/is-refraction-in-scenekit-possible