Seeding random generator

[Rick]

I don't see a seeding function in Math. How can I seed the random generator? Normally I would use:

 

math.randomseed(os.time)

 

but in sandbox mode you can't use 'os' object. Passing Time:GetCurrent() really doesn't help since it's the running time of the app. I'm stuck with the same numbers each run atm.

[shadmar]

You can use this unless you're doing randoms before rendering starts. There will be tiny variations in rendering speed.

first 5 will always be the same since GetSpeed is then 0 after first frame you will have randoms.

 

function Script:UpdateWorld()
   math.randomseed(Time:GetSpeed()*43758.5453)
   for x=0,4,1
   do
       System:Print(math.random())
   end
   System:Print(" ---- ")
end

[Rick]

I was doing this in Script:Start(). I could use this and hack around it, but LE really needs to expose some way to do a real seeding of it's random numbers. Thanks for the idea shadmar.

[shadmar]

LE really needs to expose some way to do a real seeding of it's random numbers

 

Aha..

math.randomseed(Time:Millisecs()) 

always gives you randoms even in Start().

 

Seems like Time:Millisecs() returns the system time in milliseconds, not apptime.

http://www.leadwerks.com/werkspace/page/api-reference/_/time/timemillisecs-r496

 

So there you go.. proper way

[Rick]

Interesting when I do it as the first line in Main.lua I don't get random numbers. Actually even in Start() I'm not getting random numbers.

 

function Script:Start()
math.randomseed(Time:Millisecs())

-- get random numbers and set the materials for our children
self.combo = {}
self.combo[1] = Math:Round(Math:Random(0, 9))
self.combo[2] = Math:Round(Math:Random(0, 9))
self.combo[3] = Math:Round(Math:Random(0, 9))
self.combo[4] = Math:Round(Math:Random(0, 9))
end

 

 

Looks like I'll have to use Lua's math.random() with this as LE's must use something different where doing Lua's seeding doesn't work. I figured LE's Math:Random() was just using Lua's math.random() but I guess not

[shadmar]

Yeah, I don't think you can seed LE's RNG using this.