Particle Date of Birth

[TubeSmokeGuy]

Hi,

I think it would be nice if particles, created by phoenix, would store their date of birth (frame number) in an extra data channel.
Along with thats a funcition would be nice, where you can enter a frame number at which all particles born before or born after this specific frame should be deleted or not be rendered.

Greetings

[Svetlin.Nikolov]

Yup, there is an Age channel. In the Particle Shader, you can animate the Size of the Particles depending on their age, so you can basically make a particle decrease to size 0 or even below zero at a certain age, so it won't be rendered. Check https://docs.chaosgroup.com/display/...er+%7C+PHXFoam, and look for the info on the PA button

Cheers!

[TubeSmokeGuy]

Yes. But what I want is to check if a particle was born before frame 50 or after frame 200. And if this is true then delete it. How should the individual age or lifespan of a particle be useful to check this condition? Thats why I asked for storing the number of the birthframe of each particle into its data.

[Neilg]

There may be some way to compare the particle age to the frame number with scripting. if frame number is 200 & particle age is 150 you know when it was born.
You may have to export the particles to do this, it's very likley possible in tyflow.

[TubeSmokeGuy]

Hi, yes I know about the functionallity of those tools or scripting. But I dont want to script or use some extra plugins. Thats the reason why i post it in the wishlist section. Personally I prefer to use production ready gui based solutions and as less plugins as possible. Im not happy about the situation that I need a plugin for a plugin for a plugin ... and so on. In the case of phoenix, I think it is a plugin what can create particles but unforunately offers just less solutions to handle them. I dont expect any complex particle modification possibilites like you can do with Krakatoas Magma Modifier, tyFlow or TP. Just some simple functions for testing particles against some conditions for better control.

[Ivaylo Katev]

You need a tool to delete (or not render) particles born before or after certain frame, this is NOT equal to "i need a birth date channel". Describing your needs in form of technical solution instead of the real goal is called XY problem (https://en.wikipedia.org/wiki/XY_problem). For the tool you need (the one for deleting particles), or for the any other tool that is able to use the simulation result, is totaly the same operating with age or birth frame

[Svetlin.Nikolov]

Hey,

The topic got sidetracked, but I see what you mean. Will think about a way to make this possible...

Cheers!

[TubeSmokeGuy]

You need a tool to delete (or not render) particles born before or after certain frame, this is NOT equal to "i need a birth date channel". Describing your needs in form of technical solution instead of the real goal is called XY problem (https://en.wikipedia.org/wiki/XY_problem). For the tool you need (the one for deleting particles), or for the any other tool that is able to use the simulation result, is totaly the same operating with age or birth frame

Yes, thats what I wrote in my second sentence in the start post of this thread. The idea behind, that the birth frame should be stored in the particle data, was, that you can simple test this value against a specific frame you entered, f.e. with a boolean operation. I know you can recalculate the birth frame when you test the particle age against the actual frame but this will be an extra calculation step, which wouldn't be need if you have the birth frame information stored already.