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fezz
10-31-2007, 11:24 PM
Is there a way to render point particles with a random size? I need a particle pass and need to one of the hardware shaded modes to use the ramp coloring. I chose points and added the creation expression:

particleShape1.pointSize=rand(1,3);

When it renders I get particles that change size per frame, and I want them to get a random size at the start and keep it. I also tried spheres with a radiusPP expression and got something that looked great onscreen, but when rendered got the shimmery size changing again.

Anyone got any ideas?
Aikiman
11-01-2007, 01:04 AM
pointsize is a scalar attribute which is probably why it changes every frame when a new particle is born.
apoc519
11-01-2007, 02:24 AM
use the sphere particle type and randomize them with radiusPP in the creation expression

point and streak size affects the entire particleshape and are always the same size no matter their distance from camera. Stupid points...
Aikiman
11-01-2007, 02:34 AM
woooah! that works except my graphic card is doing funny things with the rendering, doesnt like it thats for sure, must have a crappy card.
fezz
11-01-2007, 05:05 PM
use the sphere particle type and randomize them with radiusPP in the creation expression

point and streak size affects the entire particleshape and are always the same size no matter their distance from camera. Stupid points...

Yeah that was the second thing I tried, but for some reason it looks good in the camera, but hardware rendered they change size per frame :shrug:
Als
11-03-2007, 12:21 PM
In that case use blobby particles and software render.
Switch only before the render since they are lot slower to show in the viewport, and do not touch them if you can, since this is hoging the maya...
If everything else fails you can still use simple polygon sphere and instance it, using radiusPP for scale. Then render the frame and see if the size suits you. If not you can just scale down the sphere you are instancing, and get sort of interactivity.


Als
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11-03-2007, 12:21 PM
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