Time Particle confusion

[Lucas Krech]

I am trying to do an animation where the paint moves with the changing frames rather than redraws each frame. I thought this is what Time Particles do but can not seem to make them behave. I'm looking to get an animated version of this style (http://studioartist.ning.com/photo/nepf-8) where rather than a new round of splatter each frame the splatter moves about and reconfigures to make the subsequent frame. Am I misunderstanding what time particles do? It seems the examples I can find use them only for live performance style use and not auto-rotoscoping. Is there some setting outside of the Paint Preset that needs to be enabled?

[John Dalton Synthetik Software]

Here's an intro tip on time particles.

Here are some effects blog posts that use time particles.

Time particles give the path start points associated with a paint preset continuity over time. So rather than being regenerated using the Path Start Generator (Path Start control panel) for each frame in an animation, they are only generated with the Path Start Generator for the first frame in the animaiton. After that, they are moved based on the settings of the 2 Time Particle control panels. The movement controls mirror the Path Shape and Path Angle control panels of the paint synthesizer.

Since the path start points of each paint stroke are being repositioned based on movement over time, the actual paths for the paint strokes will in normal time particle presets be recomputed at the new time particle start locations.

There is a parameter in the first Time Particle control panel called Shape Track. You can use that to keep the initial path shape as the start point moves over time, or to have it more slowly change over time.

If paint splatter is coming from randomization parameters, then that could still be varying over different frames in the animation.

[Lucas Krech]

So it looks like Time particles are awesome for animating a still image or creating abstract realtime animations but are not what I want for the effect I am going for. I seem to be doing everything "right" and the particles move around the screen painting different parts of the movie in each frame and leaving others static. Perhaps the solution lies in bezier frames. But I can't get a record to internal memory into a PASeq. Should I use an edge scan to follow the bezier outline in each movie frame from the source material? Or is this something that necessitates hand drawing the animation frames?

[John Dalton Synthetik Software]

People do use time particles in auto-rotoscoped animations. It's one technique for temporally smoothing things out. If you use some kind of previous frame overdrawing technique, that might help with the screen fill issues.

Generating bezier paths off of source edges and painting them in is another popular technique for movie processing. Again, you can combine it with some kind of modify-overdraw technique.

You can use a Bezier Context action step in a PASeq to record the contents of the current layer's bezier path frame into an action step in a PASeq.

Here's a tip on PASeq Context action steps.

[Victor Ingrassia]

sounds like you would want to try to get time particles working for you... since you want the splatters to have some continuity between frames.  you might want to get a very simple time particle test going... like with 3 or 4 particles and nothing else.  1st get them to move from frame to frame, in a way that approximates the feeling you want.  Then work on increasing the number of particles, vary the shape of the particles and introduce other randomness into their motion or color or opacity.  But start with the simplest of TP's first to get a handle on what they do and how to control them.  Certain settings make them move as if they have a mind of their own... sometimes you'll stumble upon wonderful accidents that way.  Another critical thing with TP's is to let the tests you do 'play out' for lots of frames... as some settings result in the particles congregating along an edge or corner of the frame.  You want to make sure their motion over time continues as you wish.

[Lucas Krech]

Thanks! Will do.

[Lucas Krech]

The movie I am working with a single figure against a black background. If I leave the Max Stroke at 40000 I get a very small number of particles. As I reduce the number I start to get the whole figure filled in around 400-500. Above that and it is partial body only. Not sure why but at least now I can get everything drawn.

Also, I think what I want is a swarm attractor on the source edges. This would be the equivalent in other particle systems of adding a force so that gravity pulls the particles to the edges. It appears that the SA particles only respond to each other WRT swarming behaviors. So I'll look for another solution.

[John Dalton Synthetik Software]

Max Stroke = the # of time particles.

Now many paint presets default to 40000 for the Max Stroke setting, the idea being that the paint preset will run essentially forever with the assumption that the user will stop it at the appropriate time.

But 40000 time particles is way too many particles, it would eat up a huge amount of memory and be very slow.

So, there's a preference setting in the Path tab of the main preferences dialog that is called Max # of Time Particles. That overrides Max Stroke if you have time particles turned on, to avoid problems. You can set that preference to whatever you want, it just acts to limit the max number of time particles.

[John Dalton Synthetik Software]

The Path Start controls that restrict path start locations apply to the beginning locations of time particles.

And there's a Rebirth Texture Inhibit control to force them to start within a source texture range when they are reborn.

We could add something like a Texture Max Follow for the Path Angle, which would cause a generated path to move towards the highest local texture value.

A path that starts on a high texture location and tracks the image orientation is actually typically going to track the edge. So if you restrict your path starts to be in high texture areas and then setup the time particles so they are periodically reborn with the Rebirth Texture Inhibit on and set to high texture values, then you should get the 'texture swarming' behavior you want.

[Lucas Krech]

The max stroke seems to default back to 100 even when I set preferences to 1000 and set Max stroke to 500.

Also, for those following at home, while I have not solved the style I was originaly looking for, I have made some awesome accidents along the way which may well turn out more right for the project.

[liveart]

something like this?

or

this

[Michael OBannon]

The second this is really nicely done.  Any hints on how to start setting that up in SA?

Thanks,

Michael

[liveart]

the second is Victor's, so you will have to ask him about it. BTW the second is not using time particles, but it seemed to fit the brief. There is ALWAYS more than one route to a result in SA.