S_Clouds

Generates a procedural noise texture. Use the Frequency parameter to zoom in and out of the texture. The Shift Speed parameters cause the texture to automatically translate over time.

In the Sapphire Render effects submenu.


Inputs:

Background:  The current layer.   The clip to combine the clouds image with. This may be ignored if the Combine option is set to Clouds Only.
        

Parameters:

Frequency:   Default: 2,  Range: 0.01 or greater.
The spatial frequency of the clouds. Increase to zoom out, decrease to zoom in. Very high values of Frequency are clamped internally so the grain size is no smaller than a few pixels. If you want even finer grain use S_Grain or S_Clouds:Perspective instead.

Frequency Rel X:   Default: 0.4,  Range: 0.01 or greater.
The relative horizontal frequency of the texture. Increase to stretch it vertically or decrease to stretch it horizontally.

Octaves:   Integer,  Default: 8,  Range: 1 to 10.
The number of summed layers of noise. Each octave is twice the frequency and half the amplitude of the previous. A single octave gives a smooth texture. Adding octaves makes the result approach a fractal (1/f) noise texture.

Seed:   Default: 0.234,  Range: 0 or greater.
Used to initialize the random number generator. The actual seed value is not significant, but different seeds give different results and the same value should give a repeatable result.

Shift Start:   X & Y,   Default: [360 243],  Range: any.
Translation offset of the texture. Since the texture is procedurally generated it can be shifted with no repeating units or seams occurring.

Shift Speed:   X & Y,   Default: [180 0],  Range: any.
Translation speed of the texture. If non-zero, the result is automatically animated to shift at this rate. The result of animated Speed values may not be intuitive, so for variable speed motion it is usually best to set this to 0 and animate the Shift Start values instead.

Brightness1:   Default: 1,  Range: 0 or greater.
Scales the brightness of Color1. Increase for more contrast.

Color1:   Default rgb: [1 1 1].
The color of the 'brighter' parts of the texture. The colors of the result are determined by an interpolation between Color0 and Color1.

Color0:   Default rgb: [0 0 0].
The color of the 'darker' parts of the texture.

Offset0:   Default: 0,  Range: any.
Adds this value to color0. Decrease to a negative value for more contrast.

Bg Brightness:   Default: 1,  Range: 0 or greater.
The background brightness is scaled by this value before being combined with the clouds.

Combine:   Popup menu,  Default: Clouds Only.
Determines how the texture is combined with the Background.
Clouds Only:  gives only the clouds texture with no Background.
Mult:  the texture is multiplied by the Background.
Add:  the texture is added to the Background.
Screen:  the texture is blended with the Background using a screen operation.
Difference:  the result is the difference between the texture and Background.
Overlay:  the texture is combined with the Background using an overlay function.

Input Opacity:   Popup menu,  Default: Normal.
Determines the method used for dealing with opacity/transparency.
All Opaque:  Use this option to render slightly faster when the input image is fully opaque with no transparency (alpha=1).
Normal:  Process opacity normally.
As Premult:  Process as if the image is already in premultiplied form (colors have been scaled by opacity). This option also renders slightly faster than Normal mode, but the results will also be in premultiplied form, which is sometimes less correct.

Output Opacity:   Popup menu,  Default: Copy From Input.
Determines the opacity/transparency of the result. This effect does not process the opacity (alpha channel) of its input but it can either copy the opacity from the input, or output a fully opaque result.
All Opaque:  Makes the result fully opaque with no transparency.
Copy From Input:  Copies the opacity/transparency from the current layer given to this effect.

See Also:

CloudsPerspective
CloudsVortex
CloudsMultColor
CloudsColorSmooth
CloudsPsyko
Grain
Sapphire Plug-ins Introduction


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