Drop function for photon drops

Sylverant is a homebrew open source server for Phantasy Star Online. Dreamcast users still play PSO online with this server even today! This is the official forum for both the online game server as well as the open source project itself. Feel free to post and get a gathering started online! We can also show you how to get connected!

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Re: Drop function for photon drops

Post by BlueCrab » Thu Mar 13, 2014 10:50 pm

tueidj wrote:
BlueCrab wrote:The early versions of PSO are quite bad in the PRNG department, from what I remember.
That's actually surprising, I know the PRNG in the gamecube versions is a lot better than what rand() normally does (r = r * a + b). It looks more like a hash function, which would be expected for a decent PRNG.
I haven't looked at what the code for the PRNG actually does in the early versions (since I've never really cared all that much), but it is widely observed that it tends to get stuck in producing certain things as it goes. Usually, when one gets lucky in finding a decent item in the Dreamcast version, he or she will find many more good items fairly soon. At least, that's what I've seen.

Basically, it's feast or famine. There's not really much of a sane middle ground. Once again, this is just going by my experiences (and those of a few other people who I have spoken with on the subject).
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Re: Drop function for photon drops

Post by Aleron Ives » Thu Mar 13, 2014 11:42 pm

The only versions with the bad RNG are the Dreamcast ones and the PC one based on it. Sega fixed the GC RNG along with the rare rates. I might speculate that the DC one was bad because of SH4 constraints, or maybe whoever implemented that part of the game was just lazy or incompetent and chose a bad algorithm.
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Re: Drop function for photon drops

Post by BlueCrab » Thu Mar 13, 2014 11:46 pm

Aleron Ives wrote:The only versions with the bad RNG are the Dreamcast ones and the PC one based on it. Sega fixed the GC RNG along with the rare rates. I might speculate that the DC one was bad because of SH4 constraints, or maybe whoever implemented that part of the game was just lazy or incompetent and chose a bad algorithm.
At least they didn't pick as bad of an algorithm as Sony did for signing PS3 stuff for the longest time. :wink:
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By the way, I'm sure it is the latter option there (laziness/incompetence), and not really a constraint of the CPU. One can easily make an algorithm that is much more "random" without requiring that much more in the way of CPU horsepower.

Maybe one of these days, I'll have some time and find the PRNG in the Dreamcast version. Hell, I could probably patch it with the PSO Patcher disc, if I really cared to. :wink:
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Re: Drop function for photon drops

Post by RyoDC » Fri Mar 14, 2014 4:46 pm

....
How do I try to build a Dreamcast toolchain:
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Re: Drop function for photon drops

Post by Lee » Sat Mar 15, 2014 9:45 am

RyoDC wrote: Also, don't try to pass the buck to the BlueCrab, cause you was the first who started throwin' the snubs.
derp.
BlueCrab wrote: That said, I wouldn't count on any sane way to affect the PRNG on a server without either A) getting yourself banned or B) it taking far more work than would be useful to do.
BlueCrab wrote:Remember, drops are handled on the server on Blue Burst, and the server probably won't respond kindly if you try to insert your own drops into the packet stream. That, and I think the Blue Burst client required for Schtserv has anti-cheating stuff included with it too.

Simply put, if you're trying to cheat and get items you didn't earn, then you should stop now. Photon drops really aren't that hard to find. :wink:
Was totally me right.

Anyway bluecrab i've suspected for a while, it's something to do with the expand rt value in the dreamcast versions messing up. they whole funtion gets more
"unstable" the lower the base value you use for it, and well dc uses much lower base values then the later versions of the game, it's prob overflowing when quests where loaded, causing a complete rt calc fail.
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Re: Drop function for photon drops

Post by K_I_R_E_E_K » Sat Mar 15, 2014 2:40 pm

Ryo, you should know that your efforts even if they become something substancial, they will have some problems.

Before you do anything i can tell you that if someone is holding you back then that's the reason why you should keep going forward, this knowledge, this information is often to keep you from advancing and nothing more.

If you do something, certain ppl will say one of the following:
- what you did was easy, no one did it because it could have been done at anytime
- what you did used information that was said and documented "here, here and here", if anything the ppl that said this information should be credited
- what you did used information that i gave other ppl, so credit me
- i want to be credited because of "that"
- If "that" isn't right then I want to be credited because of "this"
- what you did wasn't made by "us" therefore it's bad, contains malware and shouldn't be made available at all
- What you did was indeed really nice, could you please share with us?
2 outcomes:
- if you say yes, get ready to be trashed
- if you say no because of the lack of support, interest and general disrespect then they will flip the table saying "that's the reason nothing get's done, we are trying to improve PSO and you are not helping, probably contains malware anyway."

Everytime you see info that you don't like, just ignore it and use the good info instead, there are some haters around here but luckily it's only a few of them so if you have trouble again, it will come from the same ppl again.

By all means it's possible that this doesn't refer to anyone in this topic, but the hat will serve someone. :roll:

Gl ryo
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Re: Drop function for photon drops

Post by RyoDC » Sat Mar 15, 2014 5:27 pm

Kireek, thanks for kind words.
I mean, Lee of course right, in some way.
I really could just look into a source code (cause I know what a source code is and what is it for), and really don't bother other ppl with my questions.
Lee of course deserve kudos and respect.

But I decided to go that way, so, well, it was expected that someone wouldn't like it. I can understand his feelings about some guy out of nowhere asking for drop functions and software version on server side. Largely, I'm blame in forming of such opinion on me and such evaluation of my actions.
("Who could probably this guy be? Why does he asks such a questions? Is he/she a cheater?").

So his behaviour is pretty understandable.
Before you do anything i can tell you that if someone is holding you back then that's the reason why you should keep going forward, this knowledge, this information is often to keep you from advancing and nothing more.
And that's fucking right.

But I highly assure anyone, who is distrust. I'm not going to use any of my knowledge in any harmful way. Nor do I suppose to somehow cheat or hack the game.
How do I try to build a Dreamcast toolchain:
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