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Andyjaggy
01-14-2009, 05:21 PM
Am I missing something when it comes to using a texture map to control where the particles appear. I've had this problem in the past. I load in a grayscale image to control the particle placement and it seems to have very little effect. It does effect it some, but the areas that are black still get particles on them. Grrrrr. Is there a trick I don't know about to making this work.

Mr Rid
01-14-2009, 08:04 PM
I suggest first applying the image to the color channel of the object so you can see it in GL while you scale it and such. When it is lined up where you want, copy and paste this into the Birth Rate of the object emitter, blending mode set to alpha.

I havent tried this in awhile and just noticed a bug with a quick test scene. It is working until I click Calculate, then the particles are emitting where they shouldnt...?

Andyjaggy
01-15-2009, 08:35 AM
interesting, I have just had the image set to normal. It kind of works that way, but with it on alpha it just puts the particles everywhere.

Mr Rid
01-15-2009, 03:31 PM
interesting, I have just had the image set to normal. It kind of works that way, but with it on alpha it just puts the particles everywhere.

Is working here. I've never actually needed this effect for anything. But I just discovered that if the object is animated then I have to also set the birth rate alpha to reference itself. Then be sure you click Calculate. Set the nozzle to Object Surface.
68272

Andyjaggy
01-15-2009, 04:56 PM
Okay thanks for the help.

I was doing it with just an emitter on a null object, perhaps I need actual geometry for it to work correctly?

Mr Rid
01-15-2009, 08:43 PM
Okay thanks for the help.

I was doing it with just an emitter on a null object, perhaps I need actual geometry for it to work correctly?

Ah-hah, yes, make the geometry an emitter.