In today's lecture we talked about how to handle transparent objects in CG. But have you ever wondered how people came up with premultiplied alpha, or even the idea of the alpha channel? In today's quiz, you will have a chance to learn about where it all began!
Read the article Alpha and the History of Digital Compositing on how the founders of Pixar, Alvy Ray Smith and Edwin Catmull, invented integral alpha, and submit your answers to the following questions to gradescope.
In the supersampling lecture, we discussed that insufficient resolution of an image would create "jaggies" aliasing artifacts. In the context of using bitmasks for matting, what is another cause of "jaggies" related to transparency?
Why do we have color information in our "transparent" pixels?
What type of interpolation is the provided alpha compositing formula?