PDA

View Full Version : Particles appear based on grayscale map value


Editpolygon
12-20-2007, 09:47 PM
Hey Guys,

I am sort of new to particle flow and i was wondering if someone can tell me how setup a tree in Particle flow so that my particles are born based on a alpha map.

Basically what I want to happend is have the particles creap over my surface in a really jagged/spikey way.

So for example if my object was circular I want the particles to creap along the edges and then finally converge to the center of the circular object.

I would love anyone help/tutorials.

Thank you

BrandonD
12-21-2007, 12:04 AM
Box #1's BirthTexture will give you the most control. There are some simple controls in PositionObject that let you distribute particles on an object based on a texture's values, but it won't give you the kind of control you're looking for. You could theoretically use it to place particles, then use SpeedBySurface to drive them around the edges, then use an AgeTest to trigger a new SpeedBySurface to draw them inwards. It wouldn't be easy, but creeping particles on surfaces is a bit tricky in most packages.

Editpolygon
12-21-2007, 12:10 AM
Eeeek!. I will give that a try while I know the nodes your speaking of I'm very new to particle flow so I'm not sure where to start. If anyone out there feels like doing a test scene so i can take a look I would love that :) .


But i will give it a shot myself and see if i can figure it out.


Thank you.

PsychoSilence
12-21-2007, 08:20 AM
always listen to brandon!
the older and experienced lions are the most dangerous :D hes lion king ;)

we discussed a similar topic here:
http://forums.cgsociety.org/showthread.php?p=4842773#post4842773

cheers,
anselm

Editpolygon
12-21-2007, 02:21 PM
Hey PsychoSilence,

that was some cool stuff, However I downloaded the demo of Box1 but I couldnt reproduce the effect as you did. I tried it a few times aswell and still nothing.

But I am hoping to go in a direction without the plugin not sure I will be able to purchase it.

PsychoSilence
12-21-2007, 03:07 PM
im not sure if the demo version of box#1 is the latest in terms of bug fixes. you should discuss that issue over there at orbaz.com/forum. there are serveral updates for customers.

Editpolygon
12-21-2007, 03:34 PM
im not sure if the demo version of box#1 is the latest in terms of bug fixes. you should discuss that issue over there at orbaz.com/forum. there are serveral updates for customers.

Hey

In the box 3 forum they said you can map a grayscale map into the surface spread. Do you know where in the present I can map that in>?

BrandonD
12-21-2007, 11:57 PM
With Box #3 you can extract FAR more data from geometry and manipulate it. In fact, you can have a particle read the nearest point on a mesh, find out it's color and use that in a function. It's pretty high level stuff, just takes time and a good understanding of CG tech.

charleyc
12-22-2007, 02:05 AM
Hey

In the box 3 forum they said you can map a grayscale map into the surface spread. Do you know where in the present I can map that in>?

It is not built in as a preset. You have to adjust the Data Op (load the Surface Spread into Data Op) to read the suface color and then use that to adjust the Surface Spread to your liking.

CGTalk Moderation
12-22-2007, 02:05 AM
This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.