VolumeSlice

The VolumeSlice representation draws a texture mapped two-dimensional slice from a volumetric data set already loaded into VMD using the mol volume text command, or by other means. The colors span the scalar value range of the data set, with red indicating low values and blue indicating high values in the data. The slice is drawn as a plane perpendicular to the X, Y, or Z axis, and can be positioned anywhere within the coordinate system of the volumetric data set. This feature is currently only available on machines that have full support for hardware 3-D texture mapping. On machines lacking 3-D texturing, nothing will be displayed. Future versions of VMD will greatly enhance the user interfaces and capabilities of this feature. The selectors controlling the VolumeSlice representation are the slice axis, quality level, slice position, and volume ID. The slice axis can be set to 0, 1, or 2, which correspond to the X, Y, and Z axes. The quality can be set to either 0, or 1. A quality level of 0 indicates that the slice texture map will be rendered using the color nearest the sample point. A quality level of 1 indicates that the slice texture map will be rendered using bilinear interpolation. The slice setting indicates the position of the volume slice along the chosen axis, in the coordinate system of the volumetric data, range 0 to 1. The VolID setting controls which volume data set is referenced in the representation, since multiple volumetric data sets can be loaded for a single molecule.