Hi guys, Maya fluids are amazing but expensive to use, So here is an
old trick which will help you to create low cost but very realistic
clouds.
Create a sphere (Subdivision Axis = 6, Subdivision height = 4), Duplicate them few times.
Select all spheres and go to Window > Rendering Editors >
Rendering Flags, in the flags window select all the shapes in list and
turn off double sided. This will make them more transparent, especially
at the borders.
Important : The spheres must have a high degree of
overlap or the spheres will be visible. They must NOT be scaled too
much along one axis or you will see artifacts.
Create a Lambert shading group, a ramp texture (without texture placement), a cloud texture, a sampler info utility and a reverse utility.
connect cloud1.outColor to lambert.ambientColor,
Connect the ramp1.outColor to the reverse1.input
Connect the reverse1.output to the transparency of the lambert node. We reverse the cloud color, because we want the clouds transparent where they are colored black.
Connect the sampler info facing ratio to the U Coord of the ramp,
Set the type of the ramp to URamp and change the interpolation to
exponential up. Map the Cloud to the top tab and configure as
indicated. (bottom tab just black).
The Ramp, using the sampler info facing ratio as an Input, will
modify the Cloud so that the borders of the spheres will be transparent
(black becomes white through the reverse utility node, thus totally
transparent). If the U Coord (connected to the Facing Ratio in this
example) of a U Type Ramp is 0, the output color will be the bottom
color of the ramp, if its 1, the top of the ramp is the output color.
Delete the texture placement of ramp
finally your shading network will look like this
Now apply this shader to spheres we created, and put 1 point light
inside the spheres for the scattered light, and few lights outside of
these spheres, you can also experiment with light color.
you can download the my scene file here cloud.ma (Maya 2008 version)
.
