Software Rendering
You can render 3D geometric and volumetric data using the advanced rendering capabilities of PV‑WAVE. Most of these functions are part of the standard library. The RENDER function is a system routine that performs rendering using the ray tracing technique.
In addition, the standard library contains several utility functions for gridding (2D, 3D, 4D, and spherical) and for conversion of rectangular, polar, cylindrical, and spherical coordinates.
For additional information on the rendering, gridding, and coordinate conversion functions discussed in this chapter, see the PV‑WAVE Reference.
In PV‑WAVE, advanced rendering is performed using a technique called ray tracing. Ray tracing is the process of following the path of light rays from a light source into a scene. It is one of the most powerful techniques in the image synthesis gallery. The PV‑WAVE ray-tracer handles translucency and opacity, and provides the ability to display both geometric (polygonal) and volume data within one image.
For example, it allows you to display the fluid air flow over, around, or through an object, such as an airplane wing together with a general description of the wing.
Using PV‑WAVE’s renderer, you can also generate pictures of voxel (volume) data directly, without having to convert to a polygonal iso-surface representation first.
Using the other routines in the Advanced Rendering Library, you can now easily mix the methods you employ for visualizing your data—for example, geometric data with volumetric data. (Volumetric data are 3D entities that have information inside them, instead of using polygons and lines to merely represent geometric surfaces and edges.)
These routines also provide:
3D vector field plots
iso-surfaces for polygonal representation. (An iso-surface is a pseudo-surface of constant density within a volumetric data set.)
a volume slicer for interactive subsetting and display of volumetric data
a view tool to graphically set the X, Y, Z position
“rubber sheet” mapping of an image onto a sphere