You can do that size over lifetime effect very easily by adding a blend texture to the particle system set to influence size. Use a ramp and you can add as many stops as you like, even making them grow then shrink then grow again over their age. No need for scripting at all. This method works in both BI and Cycles.
In that demo there are two identical blend textures. One controls the size and the other controls the velocity. So when the particles get bigger they move a little faster.
I can’t test it now, but I have the impression that you could animate the objects the particles are instancing and they would play the animations from the start, starting when each particle is emitted. Is it really like that?
Haha you’re bound to be screwed soon because the particle system refactor that Lukas is working on is nodal too ! Did I understand correctly ? The nodal approach is a problem for you ? It once was for me, you just need to click and then harness the power.
@K_Horseman) ins’t working if the physics in particle system is disabled (switched from “Newtonian” to “No”). It shouldn’t change the size-over-age relation, right? Could you please doublecheck?
That’s true, because No Physics actually turns off almost everything, not just the forces of gravity. But if you want particles that just sit in place on the surface there are ways to do that with Newtonian Physics. Depends on exactly the effect you want, but the simplest method in this test case would be to turn the initial normal velocity down to zero. I’ve already turned off gravity in my example, and you can turn off other force effects as well while leaving Newtonian turned on. ParticlesSizeOverAge.blend (606 KB) This method might not work in all cases (for instance if the emitter moves around, this method will leave particles behind), so I’d need to know what you’re really trying to do to offer alternative solutions.
Let’s say someone builds a car with one of the most advanced engines in the world. It has very high horsepower, it’s polished exquisitely, full of gears and parts that allow it to outperform most other cars in brilliant advanced ways.
However, the gas pedal is a binary switch that’s activated by setting an alarm clock at the times you want it to start and stop, the steering wheel is controlled by flexing your tongue on a lever, there’s only one untouchable gear, and the brake is nonexistent. I’d say that’s a fair analogy to how Blender’s particle system works.
I’ve tried to create the slowly rotating emitter with halo particles on it’s edge oriented (using texture rotation in material) outwards. So I was using extrimely low initial velocity just to get the orientation vector. And while playing with it I found that limitation with “No” physics. it kind of doesn’t make sense to me since in my universe age is function of time between two frames, not the speed of particle (excuse me Einstein ). But, anyways, I’ve managed to get there. Thanks again.
Eh. I get your point but that attitude gets us nowhere. Blender’s particle system is terrible when compared to others out there, but it’s not terrible because it’s free, and it’s being improved “despite” being free. And none of that matters because at the end of the day artists just need to get work done, so we’re all better off looking constructively for solutions than shouting on a forum about stuff we don’t like. Which brings me to…
Yeah, this would be a good time for me to reiterate something I sort of said earlier, for anyone who’s reading: Blender’s particle system is limited, clunky, unintuitive, and in desperate need of an update; however, it is not nearly as limited or impossible to use as a lot of people seem to think. At worst even if you can’t directly get the effect you want, it may still be possible to fake it effectively enough.
Developers are working on the particle system, but fixing it will require other things to be fixed first (depsgraph I’m looking at you). In the meantime don’t throw your hands up in disgust and ragequit. Someone on this forum probably knows or can invent a good method to get the effect you want even with today’s particle system. Just ask. Complaining gets you nowhere.
Uh…not that I’m accusing you of complaining, Lucidlook. That was more a general statement.
Maybe I ought to go back and see how many of the OP’s “impossible” examples I can make in Blender. I suppose if someone asks nicely…
). But, anyways, I’ve managed to get there. Thanks again.