I have created a shooting game movie

xD

Wow your parents must have had a hard time raising you!

It is. http://www.shrinemaiden.org/forum/index.php/topic,10386.msg727403.html#msg727403

Its 1 pixel hitbox if i remember correctly

The white circle in the middle. That screenshot is from a sequel and it's not visible in this game but it's about the same. Your score increases if a bullet "grazes" you by hitting the sprite but not the hitbox.

I tried the danmakufu one because I had it on my PC already, I cleared it only because you get a screen clear after every death so you can do free damage.

a heart does not remember things, the brain however, does.

Learning the patterns by heart isn't really the emphasis of the game, at least to my understanding. Sure, you'll usually have to know their basic features so you know what to expect, but after that it's about focusing on the moment and dodging immediate threats instead of doing a preset pattern of moves.

You're right, this is just the bare minimum of an all-clear run. To get a decent score you have to go after every kill and catch every bonus item at the top of the screen as well as do other risky stuff.

The attacks are generally the same every time and it's not hard to all to remember what comes next, but the exact patterns are randomized so you'll have to read and dodge.
Generally during the stages a lot of bullets are aimed exactly at you, so you can wait until they all come close and micrododge all of them at once, but the stages are meant for scoring anyway and this strategy is no good for that.

The hitbox is smaller than the model.