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creacon
03-20-2018, 08:46 AM
Hi,

I am trying out the new volumetric primitive in combination with a particle emitter to check if we can use LW for some simple FX for an upcoming production.
But I can't seem to find any parameter that allows me to fade out the particles (opacity/transparency). Any help?

Also tried the legacy HV, those have opacity but there's so many other things going wrong, so that's not a sloution.

thanks

creacon

MonroePoteet
03-20-2018, 11:46 AM
Hi,

I am trying out the new volumetric primitive in combination with a particle emitter to check if we can use LW for some simple FX for an upcoming production.
But I can't seem to find any parameter that allows me to fade out the particles (opacity/transparency). Any help?

Also tried the legacy HV, those have opacity but there's so many other things going wrong, so that's not a sloution.

thanks

creacon

This is the Texture Density parameter, but the Texture Mode has to be set to something other than "None" (e.g. Pyroclastic) for it to work. Sample scene attached, which has a single Null Volumetric. It uses an envelope to fade in and out the Texture, with a growing texture (scaled up in X,Y,Z over time) fed into the Texture input to get something other than a sphere.

140784

140783

With a more complex setup, you can get variations in color, texture, etc.

Have fun!

creacon
03-20-2018, 11:52 AM
Great,

I noticed it works even when there is no texture. So I exactly what I wanted. A strange workflow, but it works.

Thanks.

creacon

prometheus
03-20-2018, 01:41 PM
Hi,

I am trying out the new volumetric primitive in combination with a particle emitter to check if we can use LW for some simple FX for an upcoming production.
But I can't seem to find any parameter that allows me to fade out the particles (opacity/transparency). Any help?

Also tried the legacy HV, those have opacity but there's so many other things going wrong, so that's not a sloution.

thanks

creacon

there is no opacity in the new volumetrics, you lower the texture density as monroePoteet pointed out, but instead of envelopes, I would go the same route as you do with legacy hypervoxels, and use particle age in node editor and feed that in to the texture density, but you need to add an invert node and plug that in between, so the output of the particle age goes to the invert input and the output of the invert node goes to the input of texture density, otherwise you would get the fading at start and not at the end of a smoke emitter for instance.
Gosh..how complex it can sound when you describe the node flow, so much simpler when you just see an image of it:)

Note..you may also plug the particle age or relative particle age in to just the texture input instead of texture density, and you wouldnīt need the invert node, but that would need additionally multiply nodes for using an actual texture as well.

what are the issues with old legacy?
they have a better motion option with texture effect and speed effect, which isīt implemented in the new volumetrics, you need to reference something to get a certain type of turbulent motion effect..so that is a downside in the new volumetrics, they render more realistic as far as smoke would, but it is trickier to setup right.