Yes it is part of the VRay SDK, all the information you might need is with the VRay installation. You can get this even from the demo, just download it from www.chaosgroup.com
Then you will find links to the SDK documentation in the Program Files Menu…
It’s then stored locally on your computer such as…
It describes in detail, the format of the header, voxel table, voxel data and channel information with illustrated guides to how voxels are stored and example vrmesh data.
The obj2vrmesh exe is also included with the demo version: Running it from the command line with no arguments will give you the following information. Making a script which uses this to convert an exported OBJ file should be easy enough! Does the PLY format keep the vertex color channel information?
Converter of .ply .obj .bin .geo .abc and .vrscene files to .vrmesh files
Copyright © 2003-2015 by Chaos Group Ltd. All rights reserved.
Build from May 22 2015
ply2vrmesh <inputFile> [<outputFile>] [options]
ply2vrmesh <vrmeshFile> -info [options]
<inputFile> - .ply .obj .bin .geo (.hclassic) or .bgeo (.bhclassic) .abc
.prt or .vrscene file name. The string may include wildcard
<outputFile> - .vrmesh file name (extension must be specified). This
string may not include wildcards. If this is not specified
then the output is a file with the same name, but with the
.vrmesh extension. If multiple input files are specified
and <outputFile> is missing, then each input file will be
written to a separate .vrmesh file. If multiple input
files are specified and <outputFile> is also specified,
all input files are sorted in lexical order and
concatenated into one animated .vrmesh file.
-append - appends the information as a new frame to the .vrmesh file
-smoothNormals - generates smooth vertex normals. Only valid for .obj and
.geo files; always enabled for .bin files
-smoothAngle - a floating point number that specifies the angle (in
degrees) used to distinguish if the normals should be
smoothed or not. If present it automatically enables the
-flipNormals - reverses the face/vertex normals. Only valid for .obj,
.geo, .bin and .abc files
-flipVertexNormals - reverses the vertex normals. Only valid for .obj, .geo,
.bin and .abc files
-flipFaceNormals - reverses the face normals. Only valid for .obj, .geo,
.bin and .abc files
-flipYZ - swap y/z axes. Needed for some programs i.e. Poser,
ZBrush. Valid for .ply, .obj, .geo and .bin files.
-flipYPosZ - same as -flipYZ but does not reverse the sign of the z
-flipXPosZ - same as -flipYPosZ but swaps x/z axes.
-mapChannel <chanIndex> - stores the UVW coordinates to the specified mapping
channel (default is 1). Only valid for .obj and .geo
files. When exporting a mesh that will be used in Maya,
currently this must be set to 0 or the textures on the
mesh will not render properly
-disableColorSetPacking - only valid for .geo and .bgeo files; disables the
packing of float1 and float2 attributes in vertex color
-materialIDs - only valid for .geo and .bgeo files; assigns material IDs
based on the primitive groups in the file.
-materialIDs_splitGroups - only valid for .geo and .bgeo files; assigns materi
based on the primitive groups. These groups are split into
different voxels/meshes and appear in visibility lists.
-sortMaterialIDs - only valid for .geo and .bgeo files; sorts the list of
material IDs by the group name. Otherwise they are in
the same order as they appear in the .geo/.bgeo file.
-fps <fpsValue> - a floating-point number that specifies the frames per
second at which a .geo or .bin file is exported, so that
vertex velocities can be scaled accordingly. The default
-previewFaces <numFaces> - specifies the maximum number of faces in the
.vrmesh preview information. Default is 9973 faces.
-previewType <type> - specifies the method used to generate a preview.
clustering - works very fast, but is less accurate
edge_collapse - slower, but produces the best results
combined - fast, produces slightly better results than clus
face_sampling - copies triangles from the original
(very fast, but leaves a disconnected mesh)
-facesPerVoxel <numFaces> - specifies the maximum number of faces per voxel
in the resulting .vrmesh file. Default is 10000 faces.
-previewHairs <numHairs> - specifies the maximum number of hairs in the
.vrmesh preview information. Default is 500 hairs.
-segmentsPerVoxel <numSegments> - specifies maximum segments per voxel
in the resulting .vrmesh file. Default is 64000 hairs.
-hairWidthMultiplier <multiplier> - specifies the multiplier to scale
hair widths in the resulting .vrmesh file. Default is 1.0.
-previewParticles <numParticles> - specifies the maximum number of particles
in the .vrmesh preview information. Default is 20000
-particlesPerVoxel <numParticles> - specifies maximum particles per voxel
in the resulting .vrmesh file. Default is 64000 particles.
-particleWidthMultiplier <multiplier> - specifies the multiplier to scale
particles in the resulting .vrmesh file. Default is 1.0.
-mergeVoxels - merge objects before voxelization to reduce
-velocityAttrName <name> - specifies the name of the point attribute which
should be used to generate the velocity channel. By
default the ‘v’ attribute is used.
-pointSize - if specified, turns on point cloud generation and
specifies the smallest size of the points. Default is
0.0 (point cloud generation is disabled).
-velocityOffset <offset> - specifies that the starting position should be
offset by a fraction of the velocity channel, f.e. -0.25.
Only valid for .geo, .bgeo and .bin files.
-mergeFiles - merges all input files into one .vrmesh file.
Input files are specified using wildcard.
Output file (with .vrmesh extension) must be specified.
Alembic subdivision specific:
-subdivideAllMeshes - subdivide all alembic polygonal meshes,
not only subdivision objects.
-subdivisionLevel - alembic subdivision level.
-subdivideUVs <value> - specifies the subdivision of the mapping channels.
Value 0 to skip map channel subdivision and 1 to apply it.
-preserveGeomBorders - skip the subdivision for all geometry borders.
-preserveMapBordersMode <mode> - preserve map borders mode.
Mode “none” to subdivide all map borders.
Mode “internal” to preserve internal borders.
Mode “all” to preserve all map borders.
-vrsceneList - Show a list of available Nodes in the .vrscene file.
-vrsceneNodeName <name> - Node name inside the .vrscene file.
Must be specified!
-vrsceneApplyTm - Apply Node transform matrix to the mesh.
-vrsceneVelocity - Generate velocity channel (used for motion blur).
-vrsceneFrames start-end - Export animation range.
-info - show information about the specified .vrmesh file
-frame <frameIndex> - exports particular frame from the specified file.
If this option is not specified, information is printed
for each frame in the file.
Combined with -info option it shows information about the
specified frame from the .vrmesh file. Indices are 0-based.
-oneFramePerFile - exports each frame in separate file.
-padding <padding> - frame padding number between 1 and 10. Default is 4.
C:\Program Files\Chaos Group\V-Ray\3dsmax 2014 for x64 ools>