I wonder if any of Houdini's solution to create the rolling of particles? That is to say that the particles would “rotate ” rolling on the ground (with diameter)?
I am sure that the guru Houdini have how that can be solved. What i'm looking for - I want to make a particle system, where the particle is rolling when it is as sliding along the surface (particle speed is depends on the particle radius)
if someone have the tutorial - i will happy to look it)
thanks for all opinions
Rolling Particle
6352 4 2- live_fx
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- brianBurke
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it is possible to do this entirely in pops or a sopsolver, but i think the easiest way to do this is in chops post simulation. you can use the slope chop and an area chop to figure out the distance your particle traveled and then you merely need to divide that distance by 2*pi*radius to get the rotation.
here's an example of that method. feel free to let me know (anyone) if i got the maths wrong (i was probably asleep during that class in school )
good luck dude
here's an example of that method. feel free to let me know (anyone) if i got the maths wrong (i was probably asleep during that class in school )
good luck dude
- live_fx
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- old_school
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Today is the day for rolling objects from paths and particles.
All you need is distance traveled which you can derive from the POPs “speed” attribute. See the VOP POP
See the attached hip file for a solution that calculates the rotation in POPs. Again basic trig where you calculate distance traveled then divide by the circumference of your wheel/sphere to get total number of rotations up to the current time step/frame and then multiply by 360 to get rotation.
The only tricky bit is calculating the cross product after POPs to build the correct spindle axis for the tubes rolling on the terrain.
As for the CHOPs approach, have a look at the OdForce post I made earlier today. I have my own Distance CHOP asset that makes it easy. I also ranted on about how many ways to do this so in POPs is yet another way.
http://forums.odforce.net/index.php?/user/371-old-school/ [forums.odforce.net]
All you need is distance traveled which you can derive from the POPs “speed” attribute. See the VOP POP
See the attached hip file for a solution that calculates the rotation in POPs. Again basic trig where you calculate distance traveled then divide by the circumference of your wheel/sphere to get total number of rotations up to the current time step/frame and then multiply by 360 to get rotation.
The only tricky bit is calculating the cross product after POPs to build the correct spindle axis for the tubes rolling on the terrain.
As for the CHOPs approach, have a look at the OdForce post I made earlier today. I have my own Distance CHOP asset that makes it easy. I also ranted on about how many ways to do this so in POPs is yet another way.
http://forums.odforce.net/index.php?/user/371-old-school/ [forums.odforce.net]
There's at least one school like the old school!
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