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avillabon
11-29-2009, 01:13 AM
I asked this question a while back and i cant seem to find the post.. Help me again will ya?

I have a very basic particle system with Cloud (s/w) as a particle render type. Everything is working properly except for the opacityPP attr. I plugged in a grey to black ramp so they age as time progresses. In the viewport within maya i can see them fading to transparent but when i render them they dont "obey" the ramp and stay 100% opaque until they die.

I know there is a way of connecting a particle sampler to a reverse node and then to the particle cloud node but i just cant seem to remember which are the proper connections.

thanks!

Alex

Calibrix
12-08-2009, 08:31 PM
I ran into this a while back once. I believe the solution is to invert the values on your ramp. The opacity in the particle cloud shader is based on RGB values, which means white (1) is transparent and black (0) is opaque. It won't preview correctly but it will render correctly. Hope this helps.

hkspowers
12-08-2009, 09:11 PM
You need to create a particle sampler info node (we will call it PSN for short.) and middle mouse drag your PSN to your cloud shader. It will bring up your connection editor.

You want to connect the opacity of your particles to the transparency of your shader but the problem is that they are inverse of each other. 100% opaque is the opposite of 100% transparent.

So first create a reverse node then middle mouse drag your PSN onto your reverse node and connect the opacityPP to your input x,y, and z. then connect the reverse utility node to the transparency of the cloud shader. and then everything should work perfectly. So what you see in the viewport will also show up in render.

Hope this helps :beer:

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12-08-2009, 09:11 PM
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