Easy Atmosphere

DEPRECATED. This shader is unsupported, but it may still get installed with Softimage to provide compatibility with older scenes that use it. It is recommended that you replace unsupported shaders in your scenes with equivalent shaders from the current Softimage shader library.

Shader Type: Material (Soft3D)

Output: Color (RGB) value

Uses advanced numerical techniques to simulate the scattering that light undergoes when traveling through an atmosphere. You can simulate both a view of a planet from outer space and an outside view at the planet's surface.

Name	The shader's name. Enter any name you like, or leave the default.

Atmospheric

View Azimuth	Determines the position of the point of view relative to the planet's center.
Planet Radius	The planet's radius. A default value of 600 0000 m corresponds roughly to the Earth.
Thickness	This is a scale thickness of the atmosphere. The default value of 7400 m corresponds to the thickness the Earth's atmosphere would have were it uniform in density.
Density	This again is a scaling factor for the atmosphere's density. Modifying it has effects on the color of the sky and the sunset.
Dust Thickness	A smaller sphere of dust is a part of the atmosphere. This parameter defines its height.
Dust Density	The density of the dust. The dust makes a gray-colored haze appear. It will make a very effective halo around the sun as well. You may want to set this to 0 for Arctic clarity of the air. When it is set high, the sun will no longer be discernible from the glare.

Sun

Size

The size of the sun disk in degrees.

Color

The color of the sun. Our sun is very close to white.

Halo Size

Should the dust produced halo not be sufficient, this

parameter makes it possible to make the edges of the sun appear more fuzzy.

Moon

Size	The size of the moon in degrees. On the Earth, the sun and the moon are roughly the same size.
Color	The color of the moon. This is really the diffuse reflectivity of the moon, which is modeled as a ball. Our moon is really a rather dark object which only appears bright at night because the sun is so much brighter than the night.
Halo Size	Makes a halo around the moon. Good for simulating a frosty night.

Stars

Bias	A bias on the random brightness distribution.
Brightness	Scales the brightness of the stars. Sometimes they are too faint and have to be scaled to become visible.
Scale	A scaling factor for the stars.
Twinkle	The time with which the star's brightness varies.

Ground

Ground Parameters

Ground Map	Defines an image clip to use as the ground map. Click Edit to open a property page for the image clip being presently used. To retrieve a new clip, click New and indicate whether you wish to create a new clip or create one from a source.
Image View Window	This window displays the selected image. You can right-click on the image to access the Image Clip Property Editor. If the image is a sequence, use the playback controls to play the sequence image.
Spherical Mapping	The Spherical is useful for extraplanetary scenes, where you can map a geographical map on the planet using the traditional spherical mapping with two pinch points at the poles. When this mapping type is selected, the scaling is no longer in kilometers and a scaling of 1 means that the map will stretch once around the planet.
Lollipop Mapping	Lollipop is similar to cloud mapping and is useful for ground scenes where you want to place a map on the ground.
Mirror Sky	When this box is checked, the ground is just a mirror image of the ceiling.

Transformations

X, Y Scaling	The scaling of the map. In lollipop mode, it states how many kilometers each instance of the map should stretch. In spherical mode, it says how often the map wraps around the planet.
Rotation	A rotation of the map
X, Y Translation	The translation of the map. The same difference between the modes applies here as with the scale parameter.

Cloud

Cloud Parameters

Cloud Color	The color of the clouds. Mars has red ones, we like white ones... unless you live in the UK, then you want gray.
Turbulence	Creates a more turbulent-looking cloud fractal.
Altitude	This places the cloud plane in the atmosphere model. 500m is about right.
Amplitude	Defines the cloud fractal's amplitude.
Ratio	The fractal ratio. A value of 0.707 works well.
Iterations	Clouds are soft so few iterations are necessary.
Center Position	This is the center (expected value) of the fractal. A fractal value of 0 is no cloud while a fractal value of 1 is full cloud. This parameter is really a balance control between the two extremes and works with the Amplitude in placing the fractal in the 0..1 domain.
Animate	If checked, the clouds become animatable with the time parameter.
Animation Speed	Only enabled once you check the Animate option. Defines the speed of the animation.

Transformations

X, Y Scaling	The clouds are placed on the planet using a lollypop mapping. This means that there will be stretching and a seam at the South pole (negative Y direction). Scaling is in km for convenience, so that a scaling of 1 will give the clouds largest features 1-km diameter.
Rotation	This rotates the fractal. This can be useful eliminating visual artifacts due to repetitiveness in the fractal.
X, Y Translation	This offsets the cloud fractal. This can be animated to produce a wind effect.

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