The Materials and Geometry Format

Version 1.0, May 1995

Greg Ward, Lawrence Berkeley Laboratory, GJWard@Lbl.Gov

Introduction

What makes MGF special?

What does MGF look like?

MGF's place in the world of standards

MGF Basics

Entities and Contexts

Hierarchical Contexts and Transformations

Detailed MGF Example

MGF Entity Reference

MGF Translators

Initially, there are six translators for MGF data, and three of these are distributed with the MGF parser itself, mgfilt, mgf2inv and 3ds2mgf. Two of the other translators, mgf2rad and rad2mgf convert between MGF and the Radiance scene description language, and are distributed for free with the rest of the Radiance package. The sixth translator, mgf2meta, converts to a 2-dimensional line plot, and is also distributed with Radiance.

Mgfilt is a simple but useful utility that takes MGF on its input and produces MGF on its output. It uses the parser to convert entities that are not wanted or understood, and produces only the requested ones. This is useful for seeing what exactly a program must understand when it supports a given set of entities, and may serve as a substitute for linking to the parser library for programmers who wish to interpret the ASCII input directly but without all the unwanted entities. In future releases of MGF, this utility will also be handy for taking new entities and producing older versions of MGF for translators that have not yet been updated properly.

Mgf2inv converts from MGF to Inventor or VRML format. Some information is lost, because these formats do not support physical light sources or materials. 3ds2mgf converts from 3D Studio binary format to MGF. Care must be taken to correct for errors in the material descriptions, since 3D Studio is completely non-physical.

MGF Parser Library

Application Notes

Relation to Standard Practices in Computer Graphics

Relation to IESNA LM-63 and Luminaire Catalogs

Credits