Lights as a particle
polycounter lvl 18
I know it's possible to use geometry as a particle but is there a way to use a light, such as an omni light, as a particle? Tried using geometry as a light with a material but the result just isn't the same.
And this has nothing to do with light particles but there was a tutorial I saw a while ago where there was a spaceship that came in a hovered in front of a camera and the tutorial was about using dummy objects to control the hovering motion. Anyone remember where that tut was?
And this has nothing to do with light particles but there was a tutorial I saw a while ago where there was a spaceship that came in a hovered in front of a camera and the tutorial was about using dummy objects to control the hovering motion. Anyone remember where that tut was?
Replies
I use Max and I can't think of a way since Lights are not valid objects that can be selected when you try and choose objects. Other than using light emitting geometry or lens effects which would be a royal B to use I think you are stuck. I guess you could always hand animate lights to follow particles but that could drive you nuts depending on how many you have.
The only ways I can think of off hand to have geometry produce light are to use a material with 100% self illumination and use radiocity to calculate the lighting (which won't work since at best it'll only calculate the lighting for one frame) or use the light material in Vray which wasn't quite doing what I was hoping for. Any other ways that might work better?
The best way I can think of to hand animate them is to make a bunch of splines and have the lights follow them, but you lose the randomness of the motion. Which is why I was looking for that tutorial with the hovering camera but I can't seem to find that to see if that might help.
I was thinking about it and you might be able to attach lights to small objects and use Reactor to blow them around. I'm pretty sure that would do what you want and is pretty easy to set up.
- Linked a light to a cube, only the cube came out of the emitter.
- Grouped the light and the cube and selected the group to come out of the emitter, only the cube came out even though it let me select the group AS the particle, I had high hopes for this one.
- Linked the light to a dummy, couldn't select the dummy as a valid particle until I linked a cube (geometry) to the dummy, only the cube (geometry) came out.
It won't let you select anything that is not valid geometry as a particle.
The problem I think it has with using non geometry as particles is that it need the object to have mesh properties so it can preform things like the MetaParticles and collision where it splits particles into pieces and joins them back together based on their proximity/collision to/with other particles. Particles also have a life span and change shape over time, geometry can, lights and non geometric shapes don't preform like that. It looks like the system is limited to only using geometry.
Its a case of advanced features limiting the functionality of the tool. Personally I think they need to make a dumb particle emitter, one where lights and shapes can be used but there isn't an option for metaphysics. Or better yet have the particle emitter strain out everything but geometry ONLY when metaphysics is checked on.
The Shape Instance Operator sounds like it would work but it can only use Reference Objects which must be geometry, all non geometry (lights) are strained out.
[ QUOTE ]
Max Reference File:
Glossary
Reference Object
In Particle Flow, a reference object is a geometry object or collection of objects used as particles by the Shape Instance operator. It can be a single object, a group, a hierarchy, or even a compound object consisting of several elements.
[/ QUOTE ]
It is meant to help randomize and control what kinds of geometric particles are flying around. It is not designed to help hack non geometric shapes into the particle system =/ Good idea tho
I'm running a few tests with Reactor, it seems to be working. Heres a quick and dirty mini tutorial.
- Make a cube, attach an omni light, copy it a few times.
- Make a rigid body collection, Main Menu > Reactor >Create Object > Rigid Body Collection > Click in scene (it doesn't render)
- With the RB collection selected go to the modify tab add the cubes.
- Place a wind generator (same as above), or a few. Set its wind to some high number.
- Select all the cubes open the "open properties window" 4th icon from the right looks like an icon of a drop down menu, in the reactor tool bar. Set their masses to .2 or something nice and light so they blow around rather than sink past the wind.
- Preview it and see what you get. You can now set the cubes to not render and have just dancing lights.
I can go into a more step by step if you need it, I don't have time to write up a tutorial today but I could bang something out this weekend IF you need it.
Here is my test .avi and here is the max file and a screen grab.
I added volume fog to the scene so the lights where more visible the green glow has nothing to do with reactor.
Hopefully someday they will combine reactor with the particle system but until then we have to make due =/
http://www.mymentalray.com/mymr_shaders/shaders.htm
go to 'Ray Control' section and grab ctrl_objectlights, you're on your own to see if it works or not though. There is a small tutorial on there in the "Francesca" section.
If it does work it will be quick slow though as it won't link a light to your particles but make the particles lights... what you may need to do actually is attach some geometry to the particles for the shader to latch onto.
rube
That's really helpful Vig. Seems like reactor is the way to go, doesn't exactly have the control I was hoping for, but it looks like it'd produce something similar to the motion I'm trying to get. Depending on how things go with this other project I've been working on I may have some time to work on this so I'll try to get some pics up.
<font class="small">Code:</font><hr /><pre>
on ChannelsUsed pCont do
(
pCont.useTime = true
pCont.useSpeed = true
pCont.usePosition = true
)
on Init pCont do
(
Global objs
if objs == undefined then objs = #(OmniLight(), OmniLight(), OmniLight(), OmniLight(), OmniLight(), OmniLight(), OmniLight(), OmniLight(), OmniLight(), OmniLight())
)
on Proceed pCont do
(
count = pCont.NumParticles()
for i in 1 to count do
(
pCont.particleIndex = i
objs.position = pCont.particlePosition
)
)
on Release pCont do
(
)
</pre><hr />
Not much to it, and there's a bug in how the lights are made that needs to be worked out still, but it has omni lights following particles.