Hi guys, I’d like to create a simulated snowfall as the the background for a small composition I’m creating. I was thinking of using 3 separate layers of snow which I’ve already created the png images for. They are basically transparent png images with a variety of small slightly blurred white specks. The idea is that the 3 snow layers would slowly and endlessly scroll in slightly different directions down the screen overtop of some wintery background image. Before I had put much thought into how I would do this I was expecting this to be really simple, and maybe it is; but now that I’m trying to do it I’ve completely stumping myself. What is the best way of setting up the motion on these layers so it can loop infinitely and control the direction? This composition could potentially be running for days and I’ll be out of the country during the event so I’d like it to be efficient and stable. Any ideas on how I can do this part? Feeling kind of dumb right now because I am not getting it.
I’ve attached an image of the PNG layer I am trying to animate.
I found this article on how to do it on a website in CSS, but it’s hasn’t jump started my brain into figuring it out. :P Infinite CSS background image loop
@Bodysoulspirit , thanks for these. In the particle one, I don’t understand the nodes that are Changing Time and Limiting Range and then feeding into the Calculate List for the Y value of the (X,Y,Z) coordinates. Could you explain a bit for me please? What is the concept here?
In the particle one, I don’t understand the nodes that are Changing Time and Limiting Range and then feeding into the Calculate List for the Y value of the (X,Y,Z) coordinates. Could you explain a bit for me please? What is the concept here?
I think I can try to explain – please correct me if I’m wrong, @bodysoulspirit. I always find something fresh in your solutions… For one, I can sense that the simplicity in your composition(s) is not easily won – I appreciate this drive for simplicity in design.
Limit to Range is a 0 to 1 time loop. The mix(a,b,time) in Calculate List calculates a linear interpolation to animate the falling snow (50 list items, i for iterator indices – see sidebar description for Calculate List). Amount is number of items, Multiplier is distance traveled, negative value sets direction, top to bottom (just above the top to just below the bottom of the comp window so you don’t see the loop in/out points). The calculation is applied to Y position in Add Lists. (Then each new loop also gets a new random X and Z position.)
Wow @jersmi ! Thank you for the kind words, much appreciated.
And thanks for the clear explanation !
Indeed, each point gets a random x or z value, and all start at y=0,7, and they get added the -1,3 multiplier (the distance to travel from above to below the screen limit).
Regarding the formula itself mix(((i-1)*(Multiplier/Amount));(i*(Multiplier/Amount));Time), if I’m right (lol, I made this a while back ) ;
Basically it takes a distance (the multiplier (-1,3) divided by the amount of the particles) and loops this distance over time with an offset for each value in the list.
It’s like saying the first value in the list loops from 0 to 0,1, the second value in the lists from 0,1 to 0,2 …
And since the time loop lasts 1 second, and each new random point is added every second, this gives the sense that all points flow smoothly.
If that makes sense ;)
PS : Alastair, there are some variations of this in the Particles with Stock Nodes composition in the gallery.
The differences between the compositions might help ;)
) ;