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I'm trying to make an eyedropper that emits single particles when pressed, like real drops of water coming out of it. This doesn't work very well however, because at the resolution that I need the fluid to be the individual drops are completely invisible due to being rendered so tiny. Once two or three of them bunch up they suddenly become visible, though just barely as a small spastic dot. If you add a few more they jump to their final size they would appear as in a body of fluid.

Even if I could reduce the fluid resolution, there would still be a problem because the jumps in size are so large. Reducing it from 100 to a point where I have properly sized single particles at 5 will cause a horrific event to happen as soon as a few particles bunch to cross the threshold where the particles are rendered at their proper size, since the jump in scale becomes more apparent with decreasing fluid resolution. The fluid basically turns from something that looks like two or three drops to a huge ball of fluid ten times the size in an instant as soon as you add another particle.

Is there some way to reduce or completely disable this scaling effect or are single particles just not an option? I couldn't find anything in the fluid renderer settings that affects it.

(29-04-2022, 04:40 PM)locque Wrote: [ -> ]I'm trying to make an eyedropper that emits single particles when pressed, like real drops of water coming out of it.

Generally, a single particle != a drop of fluid.

A single fluid particle behaves like a rigidbody sphere for all intents and purposes. Only if there's other particles around it can exhibit fluid properties. Conceptualizing individual particles as drops is wrong, they're actually samples of a continuum fluid volume.

A drop of water is usually composed of multiple particles, surface tension being the parameter that controls how strongly the drop keeps its round shape (which is the shape that minimizes energy).

(29-04-2022, 04:40 PM)locque Wrote: [ -> ]This doesn't work very well however, because at the resolution that I need the fluid to be the individual drops are completely invisible due to being rendered so tiny. Once two or three of them bunch up they suddenly become visible, though just barely as a small spastic dot. If you add a few more they jump to their final size they would appear as in a body of fluid.

Yes, because of what I explained above. It's not possible for a single particle to accurately represent any volume of fluid. If you want individual spherical particles to represent a "drop", you'd be better off using simple sphere rigidbodies as they're cheaper.

(29-04-2022, 04:40 PM)locque Wrote: [ -> ]Is there some way to reduce or completely disable this scaling effect or are single particles just not an option? I couldn't find anything in the fluid renderer settings that affects it.

You can reduce the maximum anisotropy in the solver to the minimum value. This will ensure particles are key perfectly round and aren't scaled to fit the fluid's surface. See "Max Anisotropy":

http://obi.virtualmethodstudio.com/manua...olver.html

kind regards,

Thanks for the explanation :)

Would have been easier to do it with single particles since the dropper script would have only needed to ramp the speed attribute of an emitter set to stream up and down to match how hard the pump is being pressed, but I made it work through a more complicated script that sends short pulses to the speed attribute similar to the burst emission now.