This package provides a small collection of functions for 3D data: contour3d Uses rgl, standard, or grid graphics to render isosurfaces, or three-dimensional contours, computed by the marching cubes algorithm. image3d Crude 3d analog of image() using rgl to plot points on a three dimensional grid representing values in a three dimensional array. Assumes high values are inside and uses alpha blending to make outside points more transparent. parametric3d Plots a two-parameter surface in three dimensions. Based on Mathematica's Param3D slices3d Uses tkrplot to create an interactive slice view of three or four dimensional volume data, such as MRI data. Additional support functions are available for managing triangle mesh representations of surfaces rendering these surfaces with lighting and (minimal) shading in standard or grid graphics.