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aero opacity life

Message 1 of 2
293 Views, 1 Reply

aero opacity life

any way to control with the shader using some ramp the opcity of the particles life? or in the graph , i see the source air fog density can play with the set and add and other options to make first frames of the smoke not visible and go appearing but some official way to control it better? its like i have a cylinder very fast moving , and i dont want the smoke appear exactly on the cylinder shape , i want smoke go appearing fade in with the cylinder moving around,

and by the way since cyliner is very fast moving , even if i increase decrease time step , if aero have more quality fluid size smaller , i get this effect like smoke only appear in the cylinder shape but not in the subframes , any way to appear the smoke like a smooth trail even if very fast move? 

Message 2 of 2
in reply to: marcury



I have attached an example file that hopefully answers some of your questions.

(1) There's currently no age associated with voxels in an aero simulation, but you can use a custom property to track the time at which we emit into a certain voxel. The voxel's "age" is then the current time minus the emission time. You could then use this to control a ramp. In the scene file I have set up a volume scope that displays the numerical values of the emission time.

(2) If what you're after is just to dissipate the smoke, then you can attach a dissipation influence.

(3) To get a smooth trail you can increase the trail smoothness on the source_air node. In the example attached I have set trail smoothness to 20. Note that when having a disspation influence, some stepping in the opacity can occur because the dissipation influence currently does not take the sub-frame emission time into account.




Michael Nielsen

Principal Engineer

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