Differences between QMG 1.1 and QMG 2.0
Because of the added complexity of curved boundaries, some capabilities
of QMG 1.1 have been removed from QMG 2.0, including:
The major upgrade in QMG 2.0 is that curved geometries are now
supported. See "Geometric Objects" for more
The QMG source code has been rewritten for better performance.
For example, the following table summarizes the performance on
test case test5 running on a Pentium Pro, Windows NT 4.0
machine under Matlab 5.2.
|Version || Running time || Worst aspect ratio
|| Number of tets|
|QMG 1.1 || 25 sec ||270||11540
|QMG 2.0 ||9 sec || 121 || 16235
QMG 2.0 under Tcl/Tk supports an XDR interface for interplatform data exchage
at the binary level.
Geometric object datatypes in both Matlab and Tcl/Tk are now stored in a
"native" format instead of chunk format used in QMG 1.1. This means
that objects can be directly manipulated using high-level scripting
QMG 2.0 does not generate surface meshes.
QMG 2.0 has fewer geometric modeling operations available than QMG 1.1.
the set boolean operations are not available.
Infinite brep faces are not permitted in QMG 2.0.
The Ascii format in
QMG 2.0 is not upward compatible with QMG 1.1. To ease in the
transition, the function
is provided to read QMG 1.1 Ascii-format breps into QMG 2.0.
Several routines now have new calling sequences.
This documentation is written by
Vavasis and is
copyright ©1999 by Cornell
Permission to reproduce this documentation is granted provided this
notice remains attached. There is no warranty of any kind on
this software or its documentation. See the accompanying file
for a full statement of the copyright.
Stephen A. Vavasis, Computer Science Department, Cornell University,
Ithaca, NY 14853, firstname.lastname@example.org