Settings and Macros/GradientMapper Description

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GradientMapper

This macro gives Fusion the useful ability to map colours from a gradient to an image, based on the luminance of that image. Other channels may be used, and optionally, Perlin noise can be used to perturb the gradient being applied.

It is based on a Bitmap Mask to extract the luminance of the image. This can be softened, or its levels can be tweaked, or a different source channel can be used (e.g. RGB, hue or saturation). The resulting mask is then given to a FastNoise tool and used to modify the brightness of the Perlin noise it creates. By default, Noise Detail is set to 0 (flat) so no noise is generated, and the image's mask is used directly. FastNoise's various colour gradient controls can then be used to map colours to the mask.

Tip: In some cases, you might want to preserve the luminance of the original image while just replacing the colours. This can be easily done by using bright colours, then using a Channel Booleans tool to multiply the result of the GradientMapper with the Luminance of its source.

• Inputs

  Channel 

  Selects the colour channel of the input image used to create the mask.

  Threshold Low/High 

  The Threshold range control can be used to clip the levels of the mask.

  Softness 

  This blurs (feathers) the edges of the mask with a gaussian blur.

  Invert 

  Selecting this reverses the brightness levels of the mask.

  Noise Detail 

  Increasing this beyond 0 will add progressively detailed Perlin noise to how the colour map is applied. All noise controls will do nothing if Noise Detail is 0. See FastNoise for more information.

  Noise Contrast 

  Enhances the effect of the noise on the colour mapping.

  Discontinuous Noise 

  This creates "hard lines" in the noise map.

  Inverted Noise 

  Reverses the brightness of the noise - works best with Discontinous noise.

  Noise Center/Scale/Angle 

  Defines how the the noise is positioned over the image.

  Gradient controls 

  These define the colour gradient to be used, and how it will be applied to the image. See the Gradient Controls section for descriptions of these controls.