Formulas in Ultra Fractal can import external images. This is typically used only in direct coloring algorithms, which can subsequently use the information from the image to return colors for each pixel that is calculated. The standard Image coloring algorithm is a good example.
default: ... Image param imageParam caption = "Image" endparam
In the list of parameters in the Layer Properties tool window, the image parameter shows up as an image preview and an Open button to select an image file. See Using images for an example. The user can select any image from the computer and it will be loaded in the preview window.
To access the data from the image, you need to create an Image object from the image parameter, just like with plug-in parameters:
Image img = new @imageParam int numPixels = img.getWidth() * img.getHeight()
You can now access all pixels in the image using the methods of the built-in Image class. The Image object created is associated to the specified image parameter, so you can easily have multiple image parameters if necessary.
Note: You can also create a stand-alone Image object with new Image. For example, you could make a copy of an imported image and modify it.
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