Animating particle object color over particle lifetime

Hey BA,

It’s been a long time since I’ve been logged in here, I must say the design changes are beautiful!

More to the point, though, I have been having great difficulty finding information about my problem, so I turn to the community in hopes someone can point me in the right direction. I will admit, I am still learning the ins and outs of the 2.5/2.6+ series, so I hope this is not a dumb question. I don’t even need a full explanation if someone could point me in the right direction documentation-wise. I may just be searching the wrong terms?

In the case of this project, I am animating arrows showing the path of fluid through a water filtration system. To do this, I have multiple particle systems emitting a single arrow object along various curve paths. I am trying to have the arrows turn from red to green as they pass through the filter. I do have it set up so every arrow passes through the filter object at the same point in its (particle) lifetime, but I am stumped as to how to make the emitted object change color at that point in its life. If I animate the color of the actual object, they will simply change to green arrows after a certain time globally, not lifetime-based. Am I missing something obvious?

Just to be clear, I do understand how to do this with the actual particle emitter, but that material seems to have no bearing on the material of the emitted object. Normally, I’d just duplicate the red layer, mask the puppy out in After Effects and hue-shift the difference to green, but the angle of this shot makes it somewhat prohibitive to do that effectively.

Not sure how many posters here are from back when I last logged on, but hello to those of you who are (and my buddies - is Kbot still around lol?), and to all the newer Blender artists that have come along since. I appreciate the help and guidance and wish you all well!

hi! there is a nice particle info node but it only works in cycles, for internal you can use a ramp texture but not for particles rendered as objects… so search for an addon named RE:ticular and see if it up to date

Much thanks for the reply Liero. After posting this, I did spend a few more hours trying other search terms…this does look like a limitation in Blender after all, from what I ran across anyway. I found Re:ticular, and it looks to be an awesome script, but given the tight turnaround time on this one, around midnight I ultimately just changed my approach to the shot in order to be able to mask it in AFX. I appreciate you taking the time to reply - you did get me to look up Cycles…shows how long I have been away, I had no clue what it was!

Somewhat unrelated question - I notice some threads in these support sections have “[SOLVED]” as a status. Since I don’t think this problem has an answer right now, do I need to do anything to mark it as solved or do the mods do that? I think this is a new feature since I was last logged in.

EDIT: Nevermind, I found the “mark as solved” option :slight_smile:

I just read Liero’s post about the particle info node and there does see to be a lot of information about it. I played with it a little and found a relatively simple way to control color change of particles so I thought I would post the node setup here in case anyone else is interested.



AlanK - that is way cool. So I guess I’ll be spending a little time learning some new things. It’s probably too late for this particular project, but I will have to try that out for future ones!