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samel
12-08-2005, 02:29 PM
hello..

i did some particle-scripting for a project at work when i noticed that it would be convenient to sometimes be able to bias the rand() function.. does anyone know how to do that..?

/samel

Bonedaddy
12-08-2005, 02:39 PM
Look up the seed command. I always seed according to particleId when I need something reproducable.

samel
12-08-2005, 03:04 PM
hey, thats a nifty little command.. however..not really what i was looking for ..i want
to have control over where a rand() produces more or less output..
like a logarithmic curve...

//s

brubin
12-08-2005, 03:14 PM
hello..

i did some particle-scripting for a project at work when i noticed that it would be convenient to sometimes be able to bias the rand() function.. does anyone know how to do that..?

/samel

another suggestion:


int $randNumber ;
// if the particleId is a number devideable by 3
if(particleId % 3 == 0)
$randNumber = rand(5,10) ; // put a weight on returning numbers to be between 5 and 10
else
$randNumber = (0,10) ; // otherwise be random on a larger scale



does that help?
s

harmless
12-08-2005, 03:23 PM
define a float called $pwr
get a random number between zero and one based on the id
raise this number to the power of $pwr
cast this result as an integer because maya is...
remap this zero to one range from $min to $max where you define $min and $max

float $pwr = 3;
float $r = `rand $id 1`;
int $r = pow($r,$pwr);
float $lifeTime = `rand $r $minLife $maxLife`;

samel
12-09-2005, 09:14 AM
thanks guys.. works ok.. need to tweak things somewhat but these are good starts..

//s

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