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vlmeta Library

NAME

vlmeta_intro - Introduction to the vlmeta I/O library.

SYNOPSIS

Introduction to the vlmeta Library which comes with the ParVox system.

DESCRIPTION

The vlmeta library is designed as a wrapper to NetCDF library, providing a simple API to save and load ParVox data from NetCDF files. While the user can create the ParVox data file using direct NetCDF library calls, it is highly recommended that vlmeta library calls are used instead. With the vlmeta library, the user fills in a structure with the correct values and call one of the API functions.

The library allows the user to read and write ParVox enviroment files and ParVox input data files. The ParVox environment file contains rendering parameters, such as the transformation matrix, the viewing position, and the classification function, such as the color and opacity map, the definition of the isosurfaces, etc.. It usually has an extension ".env.nc". There are two types of input files, regular structured grid and unstructured grid. A regular structured grid file has an extension ".vox.nc". A time-sequence unstructured grid is broken into two files -- one for the definition of the grid (i.e., cells and vertices) and the other contains the physical values on the vertices. The grid definiation file has an extension ".ugrid.nc" and a grid value file has an extension ".ugval.nc". Each time step is stored in file.

VLMETA API

Environment File APIs

    vlmopen_env -- Opens a NetCDF ParVox environment file.
    vlmget_env -- Reads a vlmeta_environ structure from a NetCDF ParVox environment file.
    vlmput_env -- Writes a vlmeta_environ structure to a NetCDF ParVox environment file.

Structured Grid Data File APIs

    vlmopen_vox -- Opens a NetCDF ParVox regular structured grid voxel data file.
    vlmget_voxel4d -- Reads a vlmeta_voxel4d structure from a voxel data file, including all the voxel data.
    vlmput_voxel4d -- Writes a vlmeta_voxel4d structure to a voxel data file, including all the voxel data.
    vlmget_vdim4d -- Reads the header information for a vlmeta_voxel4d structure from a voxel data file.
    vlmput_vdim4d -- Writes the header information from a vlmeta_voxel4d structure to a voxel data file.
    vlmget_slice4d -- Reads a specified slice of data from a voxel data file.
    vlmput_slice4d -- Writes a specified slice of data to a voxel data file.

Unstructured Grid Data File APIs

    vlmopen_ugrid -- Opens a NetCDF ParVox unstructured grid definition file.
    vlmopen_ugval -- Opens a NetCDF ParVox unstructured grid value file.
    vlmget_ugdim -- Reads the dimensions of vlmeta_ugrid structure from a unstructured grid definition file or a grid value file.
    vlmput_ugdim -- Writes the dimensions from a vlmeta_ugrid structure to a unstructured grid file.
    vlmget_ugrid -- Reads the ugrid cell and vertex tables from a unstructured grid definition file.
    vlmput_ugrid -- Writes the ugrid cell and vertex tables to a unstructured grid definition file.
    vlmget_ugval -- Reads the ugrid vertex values from a unstructured grid value file.
    vlmput_ugval -- Writes the ugrid vertex values to a unstructured grid value file.

Miscellaneous APIs

vlmclose -- Closes an open ParVox environment or data file.
vlmset_def -- Fills in a vlmeta_environ structure with default values.

Data Structures

    vlmeta_environ -- Environment settings.
    vlmeta_voxel4d -- Voxel data definitions and values.
    vlmeta_ugrid -- Unstructured grid definitions and data values.