Ro3B1E wrote:
I don't really know how it is measured because I get a B on one of the hardest levels I've ever completed and it gives me nothing, but then I get an A on some 2* level and it gives me 4 pp. so i think that the system should be explained more
This is one of the thing osu fails to explain to newcomers/beginners. People usually download this for fun or from recommendation, as I did, and they just play maps without even knowing anything about performance points (pp) and star ratings until they reach mid 6-digit. I too, just played without knowing anything about pp until one of my friends who play osu told me about it.
So basically, pp is a reward system that is given for every ranked map you play (whether a map is ranked or not will be written in the map on the website). Higher pp is given for plays with 1. more jumps hit, 2. more streams hit, 3. better combo and 4. better accuracy. Also, the more misses you get, the less pp you will have at the end.
There are lots of other factors that will make the pp go down or up, but these are the main things.
So for example, if you hit a series of jumps without losing combo, depending on how hard it is to hit the jumps in a row, more pp will be rewarded. This also goes for streams; if you hit like 10 circles in a row that is right next to each other, it might increase the pp by a little (maybe like 1-5pp). However, if by any chance you miss or break your combo, you will start losing your pp, and how fast it goes down depends on how well you play after you lose the combo.
Another thing that will depend a lot will be accuracy. If a map gives like 100pp with 100% accuracy fc (full combo), it might give only like 85 pp if the accuracy is 95% (fc).
As long as you keep your combo, every 300 you get will increase your pp by any means. This is why if you lose your combo in the middle of a play, you will start losing combo until it eventually reaches an incredibly low amount of pp. Therefore, shorter maps are better/easier for getting pp, because a shorter map means less chance of losing combo frequently.
This also answers your question on the two plays you got. Even if you passed a really hard map with a grade of 'B', if you didn't keep your combo, accuracy, and did not hit any hard jumps, it is the reason why you got almost no pp at all. Same thing for your 2* play. Since you kept your accuracy high and combo for a while, you got more pp than the other play.
This isn't a detailed description of how pp works, there are lots of other things that will make the change in pp vary. Also it might be confusing but hope this answered your "pp question". Like I said, osu has to tell beginners about pp, they shouldn't expect people who are playing this game for fun to discover ranking and competition on their own.