Lootdrop Probability

[Gangrenous]

A few years ago I changed it on my server so that I could have a float for loot drop, and minimum items. I found this handy to have min and max loot amounts. Plus I wanted ultra rare drops. It looks like the official source has also changed to float, or am I wrong? I am just checking to see the differences on implementation, to see how far off my solution was since I am not as seasoned as some.

On the chance to drop, this is now in.

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chancedrop = static_cast <float> (rand()) / (static_cast <float> (RAND_MAX / 100));

This was my old code, somewhat close.

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chance = (float)rand()/((float)(RAND_MAX))*100;

I thought they did the same thing, which confused me. Having float on the left in parens did the casting to float. Is one safer?

What does the static cast actually do? I also brought in a random seed. One thing I found was that the loottable never resorts. So things at the top of the loot will always have a higher chance does that make sense? Unless you sort the loot table drops at every roll, those at the top have a higher chance. If you have a list of 20 items to be dropped unless you resort, those at the bottom may never drop. I hope that makes sense? I seem to remember bringing in chrono and using the time as a random seed.

[Gangrenous]

Okay, that is funny. I see someone had the same idea and randomized the loot tables. I thought it was intentional that they were not shuffled but someone changed it now which is great.

[Ememjr]

well on this one i have to disagree lol to me all the shuffle is mix up the outcome but does not actually fix the poor loot code

i think we went around about this a few years ago as well
i had an awesome way of doing it and thought i had committed it, but its gone


oh well

here is what i remember about it the orginal way
if there were 100 items in the table with a 5% chance to get the item
it would loop through the 100 items until you won something then stop
and repeat if there were multiple items
so you would end up winning mostly items from the top of the list, ( the reason you added shuffle

the way i beleived is that if you get to the table of 100 items then you are guaranteed 1 of those items at the propability that is listed and more like a ratio and not percent so on the 100 even if you put 100% on each one and there are a 100 items, it is still a 1% chance to get 1 of the 100
i changed mine so it was not rolling on each of the 100 and stopping but rolling once like a randdom(100) and you get that item( it was a little more complicated than that though

[Ememjr]

if your curious i do believe that this post contains the way i changed loot drops
viewtopic.php?f=88&t=4324&p=32434&hilit=loot#p32434