Particles - Wind Blowing Effect & Particle Build-Up

[pihms]

I'm always amazed to see how people, like Victor, discover new possibilities with what can be done in Moho. His short videos are an inspiration. I'm looking at some possibilities with this newer version of Moho, that I would like to see if they can be done, and if anyone knows or have tried to accomplish

Ok, a complex problem, but simple concept. First, would it be possible to add a wind effect, using the built-in wind tool that is tied to bones, somehow apply bones to the particle's layers and have those particles affected by the wind tool?
Second, are we able to have particles build up, like you would with snow or leaves?
These could be quite useful in many instances. Any thoughts?

[pihms]

Ok, I'm guessing that either these were some obviously dumb questions, or no one has answer. I'm guessing the later. Though, this could be fun to try to experiment with, which I will try over the next couple of weeks. I may have an answer to share in the near future.

[Greenlaw]

Sorry...I meant to reply when you originally posted but the main issue is that Moho particles don't recognize collision objects so they can't gather, for example, like leaves on the ground.

Not sure how convincing it would be but I can think of a few ways to maybe fake it using a combination of Moho physics and particles. I have a feeling the physics might behave too spazzy though. If I have time later today, I'll run a test.

[synthsin75]

These two threads might be relevant:
http://www.lostmarble.com/forum/viewtop ... 26#p203426
http://www.lostmarble.com/forum/viewtop ... 64#p204964

[pihms]

Sorry...I meant to reply when you originally posted but the main issue is that Moho particles don't recognize collision objects so they can't gather, for example, like leaves on the ground.

Not sure how convincing it would be but I can think of a few ways to maybe fake it using a combination of Moho physics and particles. I have a feeling the physics might behave too spazzy though. If I have time later today, I'll run a test.

That pretty much answers the question about the buildup. Not a problem, just curious if that was something that I had missed in the recent updates. That would be a nice addition, if possible, in the future.

Thanks!

[pihms]

These two threads might be relevant:
http://www.lostmarble.com/forum/viewtop ... 26#p203426
http://www.lostmarble.com/forum/viewtop ... 64#p204964

Two great examples that are addressing the question on bones and wind. I'll play around with those to see what I can create.
Thanks for the help.

[synthsin75]

For accumulation, try having the moving particle feed into an accumulating particle doing something like this:


Not much control over the speed of accumulation though.

[SuperSGL]

I have an old downloaded file of snow building up on a window sill. 446.moho was the name of it, sorry don't remember who created it no comments in the file either. I saw 2 folders of particles with 3 sizes in each. One was for close to camera the other was further away. His trick was to reference the smaller particles in the background and use physics to collect them on the window sill in a separate folder using a rectangle called control and another open rectangle (but closed shape) for the ledge no fill or outline for these. Didn't completely understand the set up but should give you some ideas.
The wind I tried putting the particles on a path and added bones to the path and tried wind dynamics or you could just animate the path I think that was in Victor's tutorial he had up recently http://www.lostmarble.com/forum/viewtopic.php?t=35115

[SuperSGL]

Found the file if you register at animestudiotutorial you can download it and check it out, here is the link https://www.animestudiotutor.com/shared_files?id=446

edit: Just checked it out more the ledge open rectangle catches the snow and the rectangle uses force 'field on' I took that out of the folder to see what it would do and the snow started bouncing around and some would pop out. The force field on the rectangle made them stick to the ledge with no movements afterwards.

[Greenlaw]

Thanks for posting this snow example SuperGL! It's very informative.

This is essentially the 'cheat' I was thinking about yesterday for the falling leaves demo I described: make a ton of duplicate layers of a leaf and use physics and a ground collision object to gather the leaves...but I wasn't sure if it was possible to make the leaves settle naturally with Moho physics. This demo shows it's doable in Moho using Force Field. (I didn't think about that...very clever!)

Anyway, the plan was if I was able to get the physics right, I could then mix in a layer of particle leaves to help fill out the density.

The snow file also demonstrates one concern I had about doing a sim like this in Moho: performance noticeably slows down with a ton of falling objects and collision. That said, the performance hit in this example is not nearly as bad as I expected.

If I have time this evening, I'll finish my leaves demo and post it here if it looks like anything.

[ggoblin]

Found the file if you register at animestudiotutorial you can download it and check it out, here is the link https://www.animestudiotutor.com/shared_files?id=446

edit: Just checked it out more the ledge open rectangle catches the snow and the rectangle uses force 'field on' I took that out of the folder to see what it would do and the snow started bouncing around and some would pop out. The force field on the rectangle made them stick to the ledge with no movements afterwards.

Thank you SuperSGL, thats a very innovative approach. I tested it both with and without a force field with interesting results. Left is with force field (light blue layer), whilst right only has the dark blue non-moving object. In both the particles have maximum friction (5) and maximum density (100) to minimize bouncing. As you can see in this example both work ok, but I think that is down to luck of the draw. As you point out in his example of the window ledges, if you remove the force field is causes some issues with a few particles jumping.



As a side note I used 70 particles, one original and the rest references to it. I thought this way if I adjust physics properties of the original it would automatically adjust the references for me.. but that doesn't seem to happen. Not sure why... all the references particles still have blue arrows indicating the reference isn't broken.

A side question: What doesn it mean to "use baked physics" ?

[ggoblin]

For accumulation, try having the moving particle feed into an accumulating particle doing something like this:


Not much control over the speed of accumulation though.

Thats an interesting approach Wes.

I tested that with the two particle players - one normal particle layer at top showering down particles, and a second particle layer at the bottom of the screen set to 'gather' particles. This was set not to be at full speed at start so we could see a build up, but as you said there is no real control of the speed of the build up. Damping was set to maximum, velocity and acceleration to 0, to ensure particles do not move about.

[ggoblin]

Thanks for posting this snow example SuperGL! It's very informative.

This is essentially the 'cheat' I was thinking about yesterday for the falling leaves demo I described: make a ton of duplicate layers of a leaf and use physics and a ground collision object to gather the leaves...but I wasn't sure if it was possible to make the leaves settle naturally with Moho physics. This demo shows it's doable in Moho using Force Field. (I didn't think about that...very clever!)

Anyway, the plan was if I was able to get the physics right, I could then mix in layer particle leaves to help fill out the density.

The snow file also demonstrates one concern I had about doing a sim like this in Moho: performance noticeably slows down with a ton of falling objects and collision. That said, the performance hit in this example is not nearly as bad as I expected.

If I have time this evening, I'll finish my leaves demo and post it here if it looks like anything.

Really looking forward to learning from that, thank you!

[Greenlaw]

A side question: What doesn it mean to "use baked physics" ?

Baked, in this context, means Moho will create a keyframe at every frame of the affected objects. This is so you can safely turn off Physics and keep the result, and frees Moho from constantly calculating the physics.

[synthsin75]

I tested it both with and without a force field with interesting results.

Nice tests.

As a side note I used 70 particles, one original and the rest references to it. I thought this way if I adjust physics properties of the original it would automatically adjust the references for me.. but that doesn't seem to happen. Not sure why... all the references particles still have blue arrows indicating the reference isn't broken.

A side question: What doesn it mean to "use baked physics" ?

Only animated properties (those with keyframes) are referenced.

Baked physics writes keyframes, so Moho can quit actively calculating the physics.