MIXD2OFF Converter

Object File Format Specifications^[1]

OFF files are used to represent a model by specifying the polygons of the model's surface. They can be ASCII files beginning with the keyword OFF or binary files beginning with the keyword OFF BINARY. The next line states the number of nodes, the number of faces, and the number of edges. The number of edges can be safely ignored.

The nodes are listed with x, y, z coordinates, written one per line. After the list of nodes, the faces are listed, with one face per line. For each face, the number of nodes is specified, followed by indices into the list of nodes.

Note that nodes are numbered starting at 0 (not starting at 1), and that numEdges will always be zero. A simple example for a cube:

OFF
8 6 0
-0.500000 -0.500000 0.500000
0.500000 -0.500000 0.500000
-0.500000 0.500000 0.500000
0.500000 0.500000 0.500000
-0.500000 0.500000 -0.500000
0.500000 0.500000 -0.500000
-0.500000 -0.500000 -0.500000
0.500000 -0.500000 -0.500000
4 0 1 3 2
4 2 3 5 4
4 4 5 7 6
4 6 7 1 0
4 1 7 5 3
4 6 0 2 4

Installation

The current MIXD2OFF version is available via a svn repository. To do a checkout you will need a svn username and password, ask Markus Probst for more information.
If you have username and password then just run:


and run make at the source code folder.

Data and System Requirements

MIXD2OFF reads standard MIXD format data files. The files should be pure IEEE binary, big-endian, 64-bit floating point, node-level. The converter has been successfully compiled and ran in: Mac OS X version 10.5 "Leopard".

Usage

There are two ways to use the converter:

1. Run mixd2off from the directory which contains your mixd data. The converter now automatically looks for an input file called mixd2off.in within the current directory.
2. If you don't have a mixd2off.in file or your current directory is not the directory which contains your mixd data. The converter automatically asks at the prompt for all the necessary information it needs to make the conversion.

Input

The following table contains the keywords used for the input file. Multiple parameters following a keyword are separated by spaces.

Key	Description	Example	Default
source %s	get number of elements and nodes from this file	source minf	minf
mien %s	file name for connectivity	mien mien	mien
mrng %s	file name for face groups	mrng mrng	mrng
mxyz %s	file name for coordinates	mxyz mxyz	mxyz
mesh %s	name of the output off file	mesh art3D.off	noname
format binary|ascii	format, in which the off file will be written	format ascii	binary
semion|off	semi-discrete formulation	semi on	off
nrng %d	number of reference groups to be considered	nrng 5	1
irng %d %d...	ids of reference groups that will be considered. This input is optional, if not given default value will be used, where m is nrng	irng 1 3 14 15	1 - m

The order of the keywords is not important except for just one case: nrng comes before irng.

Example of an mixd2off.in file:

source minf
mien mien
mrng mrng
mxyz mxyz

mesh art3D.off
format binary
semi off
nrng 5 
irng 1 3 7 8 9

References