Popping in Particle System
polycounter lvl 10
I have a smoke emitter using a 16 tile subUV texture (4x4, left to right, top to bottom) sample and I'm experiencing some popping in the middle of the sequence. It's completely random.
There will be no popping for the first ten seconds or so of the sim, (particles live 8 seconds max) and then there'll be a pop in of the particles life cycles. Some several seconds will go by then another somewhere else. It's completely random as there is no regular location, nor timing. Sometimes it'll go another ten or twenty seconds w/o a pop.
I am using a spawn rate of 4 and am running about 20-23 particles at any given time.
I've tried setting the spawn rate to one and it never pops with just one particle. Anyone else ever see this kind of thing?
I have my subuv index set to in/out of 0/0 for the first point and .9375/15 for the second point.
That is the value I extrapolated from the UDN tutorial where they use a 2x2 image and they have it set to 0/0 and .75/3.01.
There will be no popping for the first ten seconds or so of the sim, (particles live 8 seconds max) and then there'll be a pop in of the particles life cycles. Some several seconds will go by then another somewhere else. It's completely random as there is no regular location, nor timing. Sometimes it'll go another ten or twenty seconds w/o a pop.
I am using a spawn rate of 4 and am running about 20-23 particles at any given time.
I've tried setting the spawn rate to one and it never pops with just one particle. Anyone else ever see this kind of thing?
I have my subuv index set to in/out of 0/0 for the first point and .9375/15 for the second point.
That is the value I extrapolated from the UDN tutorial where they use a 2x2 image and they have it set to 0/0 and .75/3.01.
Replies
The first is: in=0/out=1 and the second is in=.9376/out=15
Sorry about the way I wrote it, it definitely wasn't clear. That's how they do the subuv index at udn but I'll definitely try your way. But do you mean an out of 16 at one? I wondered why it wasn't that way when I first looked this up and that's usually the kind of thing I try anyway but haven't in this case.
Thanks for the jog I'll get back in a bit.
It also doesn't do it with a spawn rate of two. Just three and above.
There's no reason that spawn rate should be related to a flickering issue like this, something else is wrong either in your emitter or material. Can you post a package up so I can look at your setup?
The first one to pop up in google was filehosting.org but I always associate these file hosting sites with viruses and malware.
Here is the link:
http://www.filehosting.org/file/details/404684/EmitterPoppingAssets.rar
I'd use dropbox and use the share option, always works great for me.
thisismyspamaddylol@yahoo.com
Feel free to use that if you want. I'll check out dropbox in the meantime.
But I will if it is the only way to get the file to you. :cheers:
http://www62.zippyshare.com/v/10444127/file.html
Strange, I usually see this when I try and open a file from a version of UDK newer than mine. But I am running November 2012, which I thought was the latest. Any ideas on this?
They must micro update. Would be nice to see a version name w/o having to fire up the program. BRB
My UDK install reports itself as being Version 10499 Changelist 1426632
Anyways, so it looks like your issue is related to sorting. The popping you're describing is a particle that randomly decides to jump in front of another one. Since you have lots of variation in the different modules (color, velocity, acceleration, etc), the pop is more noticeable.
You can do a couple thing to fix it. One is try changing your sort mode to 'newestFirst'. The other thing that will help is avoiding using particles that have such a strong alpha. Try moving down your 2nd point in alpha over life to a lower value than 1. Since there will be more blending because of translucency, then sorting issues like that will not be as noticeable.
Thanks for your help ImbueFX