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GPU point particle rendering artifacts

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Hi! I've come across a problem that I've never seen before. I'm rendering 1024x1024 point particles on the gpu, doing some gerstner waves, and I've noticed a vertical stripe pattern that can be seen on the particles, and can't really figure out why they are there. Pic below

In the fragment shader I'm just outputting red (1,0,0,1), and I'm sure that a lot of the particles are overlapping since they are confined in that little space.

[attachment=35820:Screenshot_1.png]

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Posted (edited)

My apologies, I should have given more details about it ( I wrote it in a rush because I had to go somewhere).

It probably is related to aliasing problems. I forgot to mention something important, I'm using an ortographic camera. With a perspective camera it doesn't happen, probably because the particles are a bit more separated (pic below).

Honestly it's the first time that I see this kind of problem because I've never played with GL_POINT particles before, not with this many at least, so I'm not sure what kind of other information would be needed, but I will be happy to provide it

http://imgur.com/eEisMZK ( I don't understand how to attch files correctly in the answer :(

 

 

I think if instead of a point you draw a little fuzzy sprite with alpha blending, it would probably look much better.

 You're probably right, I've noticed that this happens because of the amount of little points, with so litttle space between them. My short term solution would be to reduce the amount of particles and/or use a little sprite as you mention. Thanks

Edited by ramiro_fages

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Alright, I still would like to know exactly what the problem was (from the technical point of view), but I solved it by adding noise in the XY direction (with Y pointing upwards) but in camera space. Hope it helps someone :)

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