llSetAlpha Flickering

I'm having a problem with a script I just wrote. It works but the texture flickers. All I want to do fade an image in and out, but the flicker is makes it useless.

What can I do to change this to eliminate the flicker. (Note, I'm a novice LSL programmer but I have significant RL programming experience, so I can probably understand what you have to say...)

Thanks!

Wake

-------------------

float alpha = 0.5;
float distance = 0.25;
float direction = 1.0;
float step = 0.01;
float stepSource = 0.01;
float maxDistance = 0.80;

newDirStep()
{
if (step > 0) {
step = -1 * stepSource;
}else {
step = 1 * stepSource;
}
distance = llFrand(maxDistance);
//llSay (0, "newDirStep: " + (string)distance);
}

default
{

state_entry()
{
llSetTimerEvent(1);
}



timer()
{
if (distance > 0) {
alpha += step;
distance -= stepSource;
//llSay(0, "distance > 0, alpha is: " + (string) alpha + " distance is: " + (string)distance);
} else {
//llSay(0, "distance < 0, alpha is: " + (string) alpha + " distance is: " + (string)distance);
newDirStep();
}
if (alpha < 0) {
alpha = 0;
//llSay (0, "alpha < 0";
newDirStep();
} else if (alpha > 1.0) {
alpha = 1.0;
//llSay (0, "alpha > 0";
newDirStep();

}
llSetAlpha(alpha, ALL_SIDES);
}

}

I think I understand your script, and I think it looks OK What exactly do you mean by "the texture flickers"? Is it blinking on and off? Does the alpha jump to 0, or jump to 1, when it shouldn't? Could you be getting texture issues because your prim might be intersecting with another prim?

I tested your script inworld and saw the «flicker»

I played around with the settings a little and found out, that in- and decreasing the alpha-value by 0.01 could be the problem. If you choose a value of 0.1, the flicker is (mostly) gone. The transition is not as smooth anymore, but it still looks ok.

I'd try to adjust the alpha-value until the flicker is not visible anymore and the transition looks ok for you...

I had a similar problem using SetAlpha on hidden sides to force viewer updates... (using a transition from full to zero alpha) .. and would sometimes show fullbright

I eliminated the need, but if .1 changes work better it may be useful for other projects, thanks Haruki =)

I have noticed the bad practice of using channel 0 says to output debug messages in your script.

I would advise you to make use of llOwnerSay() instead to not spam other players with such messages.

hmmm, seting the jump to 0.1 is not a good workaround, I'm looking for a smooth fade, not steps.

The flicker is not the prim intersecting flicker, it is a flash that occurs everytime the alpha channel is set. But curiosuly, sometimes I do NOT see this flash. I think this may be environmental, in my sky-sandbox it works just fine, on the ground, it flashes once in awhile.

And I didn't know about the OwnerSay call, I'll do that next time I need debuging. This is my first script, I don't know much about it.

Wake

as with mine, the flash/flicker/fullbirght-look was happening ~ 1 in 50 times... I wonder if occasionally the sim isn't being caught in the middle of the update when it's getting a new change and something is happening there.... or possibly something to do with misordered or mangled packets to the viewer, or bad handling of them by the viewer.

in your case, perhaps upping the amount a little would cut down on how many continuous updates it made, thus preventing the problem in MOST cases.... 5% transparency changes shouldn't be that noticeable or perhaps just 4%