The angle that the ray refracts in the sphere is determined by the material's index of refraction. This is the constant of proportionality between the sine of the angle of incidence (from air) and the sine of the angle of refraction (in material). More information about Snell's Law can be found here: https://www.physicsclassroom.com/class/refrn/Lesson-2/Snell-s-Law
sandykzhang
Good comment Ellen! I'm curious as to how the calculation might be more complicated in the case of a material that is both partly reflective and partly transparent (i.e. still water, ice)
Pinbat
For materials that are both partly reflective and transparent, the Fresnel effect will determine how much light will be reflected/transmitted.
There is a really cool 2d raytracing demo that runs in the browser that is very thorough. You can place lens, lights, lasers, etc. Then, you can play around with how these lens affect light.
I can't help but point out that the ray outgoing from the sphere's interior is bending in the wrong direction. The sphere is higher index, therefore when passing into a lower index the ray ought to bend away from the normal, then bending to the left of the rectangle it is apparently hitting in this image. (Physics Major lol)
AronisGod
I can't help but point out that the ray outgoing from the sphere's interior is bending in the wrong direction. The sphere is higher index, therefore when passing into a lower index the ray ought to bend away from the normal, then bending to the left of the rectangle it is apparently hitting in this image. (Physics Major lol)
jchen12197
Thanks for the explanation @ellenluo! After doing project 3-1 and rewatching lecture, this diagram is making a lot more sense. I understood how the ray going from the circle to the triangle was a mirror ray using the surface normal as a reference, but I wasn't sure how to get the refractive rays. This clears things up a lot!
The angle that the ray refracts in the sphere is determined by the material's index of refraction. This is the constant of proportionality between the sine of the angle of incidence (from air) and the sine of the angle of refraction (in material). More information about Snell's Law can be found here: https://www.physicsclassroom.com/class/refrn/Lesson-2/Snell-s-Law
Good comment Ellen! I'm curious as to how the calculation might be more complicated in the case of a material that is both partly reflective and partly transparent (i.e. still water, ice)
For materials that are both partly reflective and transparent, the Fresnel effect will determine how much light will be reflected/transmitted.
https://www.scratchapixel.com/lessons/3d-basic-rendering/introduction-to-shading/reflection-refraction-fresnel
There is a really cool 2d raytracing demo that runs in the browser that is very thorough. You can place lens, lights, lasers, etc. Then, you can play around with how these lens affect light.
https://benedikt-bitterli.me/tantalum/tantalum.html
[duplicate oops]
I can't help but point out that the ray outgoing from the sphere's interior is bending in the wrong direction. The sphere is higher index, therefore when passing into a lower index the ray ought to bend away from the normal, then bending to the left of the rectangle it is apparently hitting in this image. (Physics Major lol)
I can't help but point out that the ray outgoing from the sphere's interior is bending in the wrong direction. The sphere is higher index, therefore when passing into a lower index the ray ought to bend away from the normal, then bending to the left of the rectangle it is apparently hitting in this image. (Physics Major lol)
Thanks for the explanation @ellenluo! After doing project 3-1 and rewatching lecture, this diagram is making a lot more sense. I understood how the ray going from the circle to the triangle was a mirror ray using the surface normal as a reference, but I wasn't sure how to get the refractive rays. This clears things up a lot!