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Hello,
I just can't get Obi Fluid to simulate waterdrops on a plane to behave remotely like this one:
[Image: ca32f10fbb4f8eac286453ca3012d6e3.gif]
Would you please shed some light on this problem? any help is appreciated.
Thanks.
(03-05-2019, 07:04 AM)Farzin Wrote: [ -> ]Hello,
I just can't get Obi Fluid to simulate waterdrops on a plane to behave remotely like this one:
[Image: ca32f10fbb4f8eac286453ca3012d6e3.gif]
Would you please shed some light on this problem? any help is appreciated.
Thanks.

Hi,

Without knowing what your setup is, it is impossible for us to tell if anything's wrong.

This phenomena should be able to be simulated by Obi, however using a particle-base simulation for this is complete overkill imho. It would be much easier and a lot more performant to use animated normal maps for this (either pre-baked or using a simple fluid sim in the fragment shader).

kind regards,
(03-05-2019, 02:20 PM)josemendez Wrote: [ -> ]Hi,

Without knowing what your setup is, it is impossible for us to tell if anything's wrong.

This phenomena should be able to be simulated by Obi, however using a particle-base simulation for this is complete overkill imho. It would be much easier and a lot more performant to use animated normal maps for this (either pre-baked or using a simple fluid sim in the fragment shader).

kind regards,
Thank you for the reply,

I haven't set up anything specific for this case yet because I don't know where to start! All my testimonials were not remotely close to what I showed. Only a vertical unity "Plane" 3D object and one Obi particle emitter are in the scene.

I need a real-time waterdrop effect, hence animated or pre-baked shaders do not work in this case.

If you give me some clue, like which properties are *needed* to be modified, that would be enough.

For instance, I chose "Very Sticky" for the friction properties, used different liquid properties, etc... but it just did not work.

I don't need it to be 100% realistic, I just need something the at least could resemble it.
(03-05-2019, 05:18 PM)Farzin Wrote: [ -> ]I need a real-time waterdrop effect, hence animated or pre-baked shaders do not work in this case.

Why not? an animated shader *is* fully real-time and dynamic. Something similar to this one, but with some velocity in the Y direction. This one is only 6 lines of code, so it's extremely simple:

https://www.shadertoy.com/view/ldSfDW

You could even keep track of the path followed by previous drops in a texture, to increase the probability of other drops following it, just like it happens in real life. Or have a texture to define obstacles, etc.

There's very little actual fluid dynamics involved in this effect. The resulting look it's mostly due to light refraction and the physical behavior is the result of adhesion (which a 2D shader does not even have to calculate, as it works on a plane) and surface tension forces. We will look into making a sample scene that mimics this effect in Obi so that you can follow it as a guideline. However, I still think a shader would be a far easier, faster, cheaper, and overall more practical approach to this.
(03-05-2019, 08:41 PM)josemendez Wrote: [ -> ]We will look into making a sample scene that mimics this effect in Obi.
That sounds great! I'll look into it when it is ready.
______
(03-05-2019, 08:41 PM)josemendez Wrote: [ -> ]Why not?
I need the water particles to react to the angel of the glass and speed of the wind, it is possible to use Shaders for this case and you are totally right, however, for me, it is impossible to write a shader for this specific case as I am not very professional in Shader programming.

Thanks again.