Fluid Color problem - Printable Version

Fluid Color problem - Printable Version

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Fluid Color problem - Spectra_7 - 12-08-2020

Hello.

I am having problem with few colors of the particles. Screenshot below:
[Image: s4wTE6T.png]

In the above screenshot, below buttons selects color of fluid. I set the color of fluid from ObiEmitterDiskShape component via script.
The problem is if I select purple color, it still drops blue colored fluid like in screenshot above. Same happens when I select yellow color, but it drops in red color.

Thanks.

RE: Fluid Color problem - josemendez - 12-08-2020

(12-08-2020, 01:57 PM)Spectra_7 Wrote: Hello.

I am having problem with few colors of the particles. Screenshot below:

In the above screenshot, below buttons selects color of fluid. I set the color of fluid from ObiEmitterDiskShape component via script.
The problem is if I select purple color, it still drops blue colored fluid like in screenshot above. Same happens when I select yellow color, but it drops in red color.

Thanks.

This is due to fluid absorption.

Light is progressively blocked as it enters a fluid, until there's no more light left. This is done in a multiplicative fashion, so if your fluid color is r=0.8, g=0, b=1 (purplish blue), it will degrade to r = 0, g = 0, b = 1 (pure blue) as the fluid gets thicker, because 0.8*0.8*0.8....*0.8 = 0, but 1*1*1....*1 = 1. This color shift does not happen with primitive colors, as they remain the same. Yellow and purple will degrade due to absorption, red, blue and green will not. Same effect can be observed in real life pigments.

Simply reduce your fluid materials' Thickness scale parameter, or just use a different color blending material. FluidColorOpaque is a good choice for this. From the manual:
http://obi.virtualmethodstudio.com/tutorials/fluidrendering.html

Quote:There are two different color materials/shaders included by default: FluidColorBlend and FluidColorOpaque:

FluidColorBlend uses multiplicative blending to accumulate the color of each particle.
FluidColorOpaque uses alpha blending to accumulate the color of each particle.

RE: Fluid Color problem - Spectra_7 - 12-08-2020

Reducing the thickness of material worked. Thanks!