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tcoursey
05-12-2015, 07:58 AM
I don't do much FX stuff so I don't play around in this area much. Wife wants a cool graphic for her YouTube channel...lol. Needing to have some GEMS shoot out from a particle emitter and then hit the ground and react like they really would.

So I have a particle emitter and I have instances of the gem attached, but not figuring out a way to have the bullet dynamics react in this setup. anyone with some tips or how-to's....thanks!

seghier
05-12-2015, 08:26 AM
are you try with flocking ? you find many examples in youtube

tcoursey
05-12-2015, 08:30 AM
I don't do much FX stuff so I don't play around in this area much. Wife wants a cool graphic for her YouTube channel...lol. Needing to have some GEMS shoot out from a particle emitter and then hit the ground and react like they really would.

So I have a particle emitter and I have instances of the gem attached, but not figuring out a way to have the bullet dynamics react in this setup. anyone with some tips or how-to's....thanks!

Not needing or using flocking. Just particles with dynamics. All I can find is FX Linker old stuff....when I search.

seghier
05-12-2015, 08:35 AM
i think you can replace particles by any object ; is this impossible ?

tcoursey
05-12-2015, 08:38 AM
i think you can replace particles by any object ; is this impossible ?

Yes I have the particles replaced with the gems....just need to incorporate bullet dynamics so when they fall they react to collisions and ground. Any help there?

seghier
05-12-2015, 08:38 AM
maybe advanced placement will give you nice result


https://www.youtube.com/watch?v=jjDZKQiAU-M

tcoursey
05-12-2015, 08:44 AM
maybe advanced placement will give you nice result


https://www.youtube.com/watch?v=jjDZKQiAU-M

Ah, possibly...really didn't want to buy another plugin but have run across this plugin in previous results...forgot about it though. Yea it looks like that has some dynamics going on...hmm....thanks.

Anyone with LW native options though?

seghier
05-12-2015, 09:04 AM
i asked about collision between particles since long time but i think this is not possible with lightwave
you will see objects intersect and give wrong result

prometheus
05-12-2015, 09:21 AM
Do not work with instances and bullet dynamics and expect it to work, lightwave do not have instancing working with dynamics.

the route would be to ..
1. make sure all your objects is real polygeometry and not instances, and use bullet dynamics on all of those.

2. you can replace particles (flocking or native particles) with instances or objects, if you Add instances to particles or flocking, they will only take on the properties of the particles themself, not actual self collision...there are some self collisions you can set up with particles itself, but it will not be accurate to calculate for the other objects, only a rough aproximation.


3. you could use "proxy objects" low res objects that are similar to your "hero object" and simulate with bullet and then replace I think.


for replacing particles, you can either use particle fx linker, use the dynamic particle fx linker, or you can clone them with dpont nodes, it is a little pointless though, since if you replace the particles with objects, you would be better off simulating them all with bullet without particles.




Michael

prometheus
05-12-2015, 09:25 AM
i asked about collision between particles since long time but i think this is not possible with lightwave
you will see objects intersect and give wrong result

I think I have mentioned that before to you, collision between particles Is possible, objects intersecting is another thing...a particle is not an object....a particle needs a particle radius size and have self interaction activated, and they will bounce against any other particle nearby....but do not confuse that with object collisions, and if you link objects to a particle...it will as I mentioned above only take on the particle motion.

so if you want interaction between objects, you might as well skip particle linking and run a bullet simulation on all objects, but donīt try instances...only real poly geometry will work, a solution might be to use low res obj in a dynamic simulation and then replace with instances, but it will Never be exact based on instance geometry..it will be exact based on whatever lowres object used that might resemble the higher instanced version.

seghier
05-12-2015, 09:30 AM
I think I have mentioned that before to you, collision between particles Is possible, objects intersecting is another thing...a particle is not an object....a particle needs a particle radius size and have self interaction activated, and they will bounce against any other particle nearby....but do not confuse that with object collisions, and if you link objects to a particle...it will as I mentioned above only take on the particle motion.

so if you want interaction between objects, you might as well skip particle linking and run a bullet simulation on all objects, but donīt try instances...only real poly geometry will work.

thanks Michael
yes of course and i waited your test :D
i asked about that since months to create bubbles and i remember they told me it is not possible like bullet collision
if we create leaves can particles collision give nice result without intersection ?

prometheus
05-12-2015, 09:44 AM
thanks Michael
yes of course and i waited your test :D
i asked about that since months to create bubbles and i remember they told me it is not possible like bullet collision
if we create leaves can particles collision give nice result without intersection ?


if any object is within the same size as the particles size radius is, then no intersection is possible, so if you have a leaf object of 10 cm, a suggested particle radius size (it it spherical) would be above 10 cm.

But note this...particle collisons it just a rough dynamic particle simulation of collisions, it isnīt as realistic in behavior as the bullet engine, you can have particle interaction..but at a rough level, so it is better to use bullet without particles.

you can use wind forces in bullet to blow around leaves too.

seghier
05-12-2015, 10:29 AM
if any object is within the same size as the particles size radius is, then no intersection is possible, so if you have a leaf object of 10 cm, a suggested particle radius size (it it spherical) would be above 10 cm.

But note this...particle collisons it just a rough dynamic particle simulation of collisions, it isnīt as realistic in behavior as the bullet engine, you can have particle interaction..but at a rough level, so it is better to use bullet without particles.

you can use wind forces in bullet to blow around leaves too.

thanks very much Michael :) ; in blender exist very nice plugin use particles and realistic collision called molecular


https://www.youtube.com/watch?v=fk67wfAFR24

MonroePoteet
05-12-2015, 01:43 PM
It might not meet your needs, but here's a quick scene using classic FX rather than Bullet. As has been mentioned, the collision detection of particles is just a sphere based upon the particle size, and in general, LW's collision detection (both in classic FX and Bullet) is pretty poor, IMO. However, it's still a kind of nice effect.

You'll need to press the Calculate button in the FX tab of the Emitter object to calculate the particles. There's a nodal surface color to change the color and translucency of each gem.

Good luck!

mTp