I am trying to create a bubble particle effect and to do so I rendered a Image sequence of bubbles rising.
It looks pretty nice but using 200 1024x1024 images for a flipbook seems to be a little over the top.
I tought I could maybe do it with using one of the latest introduced features: a media texture.
The material works perfect, but the only problem is that the video plays constant and does not start with the creation of the particle (like a flipbook texture does).
Is there a way to tell each particle to start the video from the beginning?
I would recommend trying the following implementation.
Generate a Sphere Normal Map, a spherical gradient texture and Mask texture. Use UV distortion to displace the mask, and use a dynamic parameter to randomize the UV distortion per emitted particle.
Plug the Normal into your Normal, and then use your spherical gradient texture to mask where you would like to see refraction. You can try plugging your Normal into a Multiply and a 3Vector to scale the normal over the life of your particle (normalize the output of the multiply)
You can do all of this with two 256 textures, DXT5 if you channel pack your alphas.
Here’s a video that could help you with the random motion…
In the second video Alan covers UV distortion for creation of Fire, you can apply this same principle to your bubbles.
I’m not sure if it will be as good as this, one of the frames of my created bubble animation.
I found out that it doesn’t look that bad with 512x512 and a SubUV Map (and it works pretty well)
I also found a way to select one of four different texture maps for the particle at the spawn (made the red channel random between 0 and 1 at particle generation and used that channel with 4 IF nodes to check for the value plugged into a lerp…)
That looks pretty nice, you could achieve a similar look using mesh emitters and WPO…the larger bubbles could be 3d.
I was under the impression you wanted much simpler shapes (all of those smaller bubbles could easily work with the technique I described, so you wouldn’t necessarily need a flipbook, and your larger bubbles could be 3d.
the problem is that bubbles have a very unique behaviour which is really, really hard to do with anything else… I tried it.
The missing “real” reflection on additive materials combined with the 0,7x IOR of bubbles is pretty hard to do.
Also bubbles break up and join again sometimes. Smaller bubbles move slower than bigger bubbles… and so on and so on
