Texture as particles` goal

Become a member of the CGSociety

Connect, Share, and Learn with our Large Growing CG Art Community. It's Free!

THREAD CLOSED
 
Thread Tools Display Modes
  08 August 2008
Texture as particles` goal

Hi.

Is there a way to use texture as a goal?

For example:

I have grayscale texture on a poly grid, white letters on a black background and I want particles to go towards white areas only.

I`ve tried couple of things but nothing works.
I don`t know why, but even Filter by Texture Map for my Emitter doesn`t work and I`m doin everythin as in a help file (chapter Emitting Particles Based on a Texture Map).

Any suggestions, please?
 
  08 August 2008
The Get Geometry Sample node has a parameter for filtering but it only works with scalars, integers and Booleans already available on the sampled geometry. So what you'd need to do is use an ICE tree to read a texture map at the surface point positions, get the brightness, and store that as a custom attribute. You could do that in a separate tree in the Modeling region so that it doesn't keep evaluating every frame. Then you can use Get Geometry Sample, select the attribute as a filter, and use the result with the various Goal compounds.
 
  08 August 2008
Thanks for fast reply!

I thought it would be easy, but as I`m a simple animator and ICE user wannabe that seems to be beyond my skills

I`m goin to try, tho. Thanks
 
  08 August 2008
After reading this thread I decided to try that method (courtesy of grahamef)... this is what I came up with:

http://home.comcast.net/~jgj252/Tem...alTestScene.zip

(Scene uses the "jollyroger" image from the XSI_SAMPLES project.)

A couple of things I didn't get 'round to figuring out:
1) How to move the target goal points around a smidge to avoid the particles all lining up in a grid pattern.
2) How to get the color values from a Material image map, instead of a Texture Map Property.

-Jim
 
  08 August 2008
Oh, it works

Quote: How to move the target goal points around a smidge to avoid the particles all lining up in a grid pattern.


I`ve done that by changin samplin method from Points to Surface.

Thanks
 
  08 August 2008
Originally Posted by jgj: 2) How to get the color values from a Material image map, instead of a Texture Map Property.


There's no way to do that. You need to use a texture map. Of course, the texture map can use the same UV set and image clip as the material so it's barely adding any weight to the scene.
 
  08 August 2008
Thread automatically closed

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.
__________________
CGTalk Policy/Legalities
Note that as CGTalk Members, you agree to the terms and conditions of using this website.
 
Thread Closed share thread



Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
CGSociety
Society of Digital Artists
www.cgsociety.org

Powered by vBulletin
Copyright 2000 - 2006,
Jelsoft Enterprises Ltd.
Minimize Ads
Forum Jump
Miscellaneous

All times are GMT. The time now is 02:05 PM.


Powered by vBulletin
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.