# Scripting Node

The scripting node allows to perform operations on the data using a javascript-like syntax.

This node can be added to any other node, for example a Volume Node (i.e. to produce a volume rendering of the data) or a Slice Node.

## Example using 2D images

Using the Gigapixel David dataset at the URL: http://atlantis.sci.utah.edu/mod_visus?dataset=david

we can apply scripting using some of the predefined filters/scripts.

For example from the original image:

Using a "2D/Emboss" script you will get something like the following:

## Examples using a vector field

In the following examples we will use a vector field from a large scale combustion dataset. You can open this dataset with your ViSUS Viewer using "Open URL" and this address: http://atlantis.sci.utah.edu/mod_visus?dataset=lifted_time

A Volume Node for a vector field will visualize a volume rendering as following (using a "Gamma" palette):

Since the data has 3 components the default visualization uses the 3 components as RGB channels.

If we want to evaluate and visualize the squared magnitude of this (three-dimensional) vector field the user can simply insert a scripting node with the following script:

output= ((1.0*input[0])*input[0]) + ((1.0*input[1])*input[1]) + ((1.0*input[2])*input[2]);

Where the `input`

field represent the input data that enter the scripting node, the output represents the result of the computation.

The output will be a scalar field that will be rendered as following:

Another example using a vector field is to compute a 2D **Linear Integral Convolution** (LIC), this can be done using the following simple script:

output=Visus.Array.lic(input,0,1);

where the second and third parameters of the *lic* function are the vector's components that we want to use for the computation.

The result will be like the following (using a "Banded" palette) adding this script to a Slice Node: