Big Bang and Binary System

 Last week, I spent many hours on how to make an image spin at a certain speed by using "Big Bang."

 I felt the basic use of "Big Bang" is difficult. This week, it was getting harder, though. I was so confused about the contents of the first class after reading week, which introduced "timer", "on-key", and "struct." It was not like previous class which uses only one model. This time, I was told to combine three models to spin together at different speed by using "struct." Having done this, the background of one model was still not very clear and the professor taught us to use "make-color." The steps were so complex that I did not figure them out. For example, how to make different speed for each model. I remembered  there was a function like:

(Rotate (* -1 MH-speed 210) MH)

The second day, binary system was introduced. Compared to "Big Bang", binary was easier to understand. If I want to write 37 in the binary system on base 2, then I just divide the number by 2 every time. However, I was not sure when I should carry "1" in the multiplication of binary.

I learned many new things in this week and it would take some time for me to digest them.