basic MEL help please
 

Hi there.

I want to create the effect of sheet lightning, by randomising the intensity of a point light.

I can get this to happen, but i need it so that i can vary the time between flashes, like i need an avg random 30 frames between changes.

i came up with this, having not much programming or MEL experience,


//setup values
int $mycount;
$mycount = rand(20,30);
int $i;

//loop for 380 frames
for ($i=1; $i <380; $i++) {

//check random value against frame value
if (frame == $mycount) {

//change light intensity
pointLightShape1.intensity = rand(0,1);

//increase random value to progress
$mycount += $mycount;
}
}


and now I'm stuck. can anyone point out where i went wrong?
it only changes the intensity once. and then not even everytime i play it through.
or perhaps a less round about way of doing it?
thanks!!

Adam.

wait.. let me first try to figure out what youre trying to do..... as the animation plays, you want random flashes every 30 frames?

-Emo

a random vaule for the illumination yes.

and approximately every 30 frames. I wanted to randomise the time between flashes. so approx 30 frames, say a random interval between 10 and 40.

this would be easier as an expression:

right click the intensity in the channel box and add this:

if(frame % 30 == 0)
{
pointLightShape1.intensity = rand(0,5);
}

What you are doing is using the modulus function (%) to check if the frame divides equally by thirty and then setting the intensity by expression.

Simple :ninja:

Alan

thanks Alan!
i was at a bit of a loss how to do the time delay properly.
that would only make it exactly 30 frames though?
i want it to be more random than that.

like lightning
a couple of quick flashes, a pause, flash, pause, some more quick, or whatever.

well if you want it that specific then you may have to key it. You can use a random number instead of the frame number:

int $frameChange = rand(10, 40);
if(frame % $frameChange == 0)
{
pointLightShape1.intensity = rand(0,5);
}

Alan

no no, not specific, random is what i want.
that random function should work a treat,

thanks for that Alan.
I really appreciate the effort you make helping out me and other newbies.

this is what i ended up with, if anyone was interested in how it ended up working.


//setup values

int $mynumber;
int $i;

//loop for 380 frames

for ($i=1; $i <380; $i++) {

$mynumber = rand(50,80);

if (frame % $mynumber == 0) {
pointLightShape1.intensity = rand(0,1);

//increase random value to progress

$mynumber += $mynumber;
}
}