Actually one of the reason why I wrote this program is to test the terminal performances. When I'm searching the benchmark data of Alacritty, I found this issue https://github.com/alacritty/alacritty/issues/289#issue-2001... where the existing Matrix rain program "cmatrix" is mentioned. I tried "cmatrix" in my terminal (I'm using a terminal which I wrote from scratch for myself) and found that the Matrix rain of "cmatrix" is cheaper than I expected. That is the reason why I wrote "cxxmatrix", a version with additional optical effects written in C++.