Isosurface

The Isosurface representation computes and draws a surface within a volumetric data field, on a 3-D surface corresponding to points with a single scalar value. There are several settings which control how the isosurface is displayed. The ``Box Only'' control causes the volume data bounding box and coordinate axes to be drawn rather than the isosurface for the data. This is often useful when first working with volumetric data, and checking that the coordinate systems of the volume data and the molecule match. The wireframe control can be set to 0, 1, or 2. When the wireframe control is set to 0, the isosurface is drawn using a solid space filling representation. When the wireframe control is set to 1, the isosurface is drawn using lines. When the wireframe control is set to 2, the surface is drawn using only points at the appropriate isovalue samples. The Isoval control selects the value for which the isosurface will be computed. The VolID control selects which volume dataset is used for the isosurface calculation, since a given molecule can contain multiple volumetric data sets. This and other volumetric display features will be greatly expanded in forthcoming releases of VMD.