What is this about?
One of my experiment that allow smooth drawing black border via eventing. Modified to be user friendly and easy to study. Normally, we don't want black border in our game. But this black border can be treated as a cinematic effect.
It's designed to be convenient. User only need set a variable to an array rect, and playing with the switches.
It's designed to be "smooth". Thus explained why it had to use parallel process.
Recommended usage for whatever suit your need, Be creative.
In the end this is done via eventing. But then you might need this rare kind of feature. Especially when you participate in certain rpg maker challenge where plugins are unallowed.
This one is free to use. I made it for study purpose.
At last, let me know if there's something you don't understand or what would you like to suggest to improve it.