### 10 Displaying an Iso-surface

10.1 Use
10.2 Notes
 file: isosurface.net example data file: field.general

This network displays an iso-surface5 corresponding to some value in a data cube. The colour of the iso-surface varies to mimic the effect of light reflecting off the surface. The surface is plotted in its correct relative position inside a set of axes representing the edges of the data cube.

#### 10.1 Use

The network is shown in Figure 13.

• To specify the data cube to be read double-click on the ‘Import’ module and follow the instructions in Section 4.1.
• To specify the value for the iso-surface double-click on the ‘Scalar’ module at the top of the network and enter the required value. If you have no knowledge of the range of values in the cube, and hence no idea of suitable value, use network histogram.net (see Section 7) to find the minimum, maximum and distribution of values in the data.

#### 10.2 Notes

Module ‘ShowBox’ extracts the bounding box of the data cube. ‘Isosurface’ computes the iso-surface and ‘AutoColor’ colours it. ‘Collect’ combines the bounding box and iso-surface.

5An iso-surface is the analogue in three-dimensional gridded data of a single contour in two-dimensional gridded data. That is, it is a surface defined by some constant value of the dependent variable.