NAME

vpStoreRawVolume, vpStoreMinMaxOctree, vpStoreClassifiedVolume, vpStoreContext - store volume data structures to a file

SYNOPSIS

#include <volpack.h>

vpResult

vpStoreRawVolume(vpc, fd)

vpContext *vpc;

int fd;

vpResult

vpStoreMinMaxOctree(vpc, fd)

vpContext *vpc;

int fd;

vpResult

vpStoreClassifiedVolume(vpc, fd)

vpContext *vpc;

int fd;

vpResult

vpStoreContext(vpc, fd)

vpContext *vpc;

int fd;

ARGUMENTS

vpc

VolPack context from vpCreateContext.

fd

File descriptor from open(2), open for writing.

DESCRIPTION

These functions are used to store volume data structures from a rendering context into files in the format read by the VolPack file reading routines (see vpLoadRawVolume(3)).

vpStoreRawVolume creates a 3D voxel array file. The file includes information about the size of the volume and the layout of the voxels as well as the volume data itself.

vpStoreMinMaxOctree creates a min-max octree file. The file includes information about the size of the volume and the layout of the voxels as well as the octree itself.

vpStoreClassifiedVolume creates a preclassified volume data file. The file includes information about the size of the volume and the layout of the voxels as well as the volume data itself.

vpStoreContext creates a rendering context file. The file includes all rendering parameters except volume data and callback functions. The contents of any lookup tables for shading and classification are also stored.

The function used to write data to the files can be set by calling vpSetCallback with the VP_WRITE_FUNC option. This could be used to implement a file-compression system, for example.

STATE VARIABLES

The current file I/O parameters can be retrieved with the following state variable codes (see vpGeti(3)): VP_WRITE_FUNC.

ERRORS

The normal return value is VP_OK. The following error return values are possible:

VPERROR_IO

The file writing function returned an error value (in which case the external variable errno should contain an operating-system specific error code), or the file system is full.

VPERROR_BAD_VOLUME

The volume dimensions are invalid, or there is no voxel data in the context.

VPERROR_BAD_SIZE

There is no min-max octree in the volume (vpStoreMinMaxOctree only).

VPERROR_BAD_VOXEL

The voxel fields in the rendering context have not been properly defined.

SEE ALSO

VolPack(3), vpCreateContext(3), vpLoadRawVolume(3)