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)