soap bubbles

[flipside]

Hi,

I'm looking for a very old post, I believe by Vlado. It was about a very real soap bubble floating in the air (I think it was even animated). I searched but couldn't find it, found some dead links too.

I need to render one (animated), hyper realistic with all the nice colours in it. I didn't even try it yet, was just looking on the forum for that one post, so if anyone finds it, please let me know

Then second question, how would you animate a soap bubble popping? Just looking for some hints as I'm stuck on some other projects for now and won't have much time for testing later on.

Any help on my extremely general questions always welcome

[joconnell]

Try using a reflection map of a really swirly coloured map rather than anything fancy - try this procedural as a start - http://www.morphographic.com/Diversi...ColorNoise.htm

As for the pop cut it off at a specific frame and maybe use pflow to make some little droplets of water fly off and down.

[gilpo]

If I remember right, a bubble pops like a balloon. It basically 'tears' from one side to the other. I would probably try animating a slice modifier with the remove top (or remove bottom) option moving from one side to the other. Do it over just a couple frames and with some particle generation at the final frame like joconnell suggested.

No clue on the material. Sorry man.

[vlado]

I remember the post, I probably even have the bubble picture somewhere on my hard-drive... have to look for it.

Best regards,
Vlado

[Timmeh]

This may be of some use.

http://vray.info/topics/t0060.asp

This post has an example image, animation and max file.

[vlado]

Yes, that's the one... Thanks to Egz for keeping it on vray.info

Best regards,
Vlado

[Timmeh]

Balloons popping

http://www.flickr.com/photos/cdibona/sets/801894/



And for high speed film of a soap bubble popping:

http://www.engr.colostate.edu/~dga/high_speed_video/

Scroll down the page to Fluid Mechanics.

[flipside]

Wow thanks for all replies!

Here's my own quick test:


If you search for pictures in google, there are many different looks, some have very pronounced swirls and strong colours, some are more subtle like vlado's example.

Vlado, any idea why you used the rgb multiply map in your material? Here's a screenshot:


It doesn't seem to do much if I use the planet map inside this rgb multiply or directly. (this rgb multiply sits in the second slot of a falloff map in the reflection slot)

Thanks for all the help already!

[flipside]

Here's another problem that I encounter quite often.

I need to place this bubble inside of some footage. Inside the bubble will be an objects which is also reflective.

So I set the footage as the max background. I load a hdri map in the vray reflection override. I load the footage in the vray refraction override (otherwise the hdri shows through the bubble).

But then I get this result:


The car is reflecting the footage (srcreen mapped) instead of the hdri map because it is actually reflecting the refractions of the bubble (and the bubble refracts the footage - still following? )

This results in wrong looking reflections on the car (it looks almost as if it is partially transparant because of the screen mapped reflections of the footage).

Here's an image with the vray refraction override turned of. The reflections on the car are correct now (hdri reflections), but the refractions in the bubble show the hdri instead of the footage.


How can I solve this?

[vlado]

You can use the environment override inside the car/bubble materials, and then use the Environment priority option of VRayMtl to control which environment is used when (e.g. you'd assign a higher Env. priority to the car environment override since it needs to survive when it goes through the bubble and its override). And if you need to have separate reflection and refraction overrides on a material, you can make them separate materials and layer them with a VRayBlendMtl material.

Best regards,
Vlado

[flipside]

thanks vlado, will try that feature!

[sv]

flipside these look great.
I've had to do some R&D into this recently, although we didn't have the time to get very far....
your tests look absolutely spot on, really amazing stuff.

Vlado too - beautiful realism....

I should have looked on here first!

[flipside]

Hi,

I thought I got it working with the screen mapped reflections, but it's not.

The car now reflects the hdri, but also the screen mapped background.




I put the hdri in the car material, and set environment priority to 1. The bubble has no map in environment slot. Vray reflection override has the hdri, and refraction override has the backdrop image.

What am I doing wrong here?

Also, from the moment I start using the backdrop image, I lose almost all reflections:

image with hdri for refl and refr and backdrop:



Image with backdrop and also backdrop in refraction override:



Increasing reflections:




Any idea why this is happening? It seems as if the bottom of the bubble won't reflect the hdri as before (inside reflections).


Thanks,

wouter

[flipside]

What makes it even more weird is that when using Mblur and DOF, these backdrop reflections coming through, still appear sharp:

[RErender]

For the motion blur that's what I'd expect since the refracted backdrop is not moving, not sure about the dof though