PrimEx GEANT4 Gallery
"Why GEANT4?" you may ask. Well, maybe what you
really mean is "Why GEANT4 when you already have simulation code for GEANT3?".
The short answer is that GEANT4 has a much better visualization package. While
still a little effort was needed, GEANT4 makes it much easier to produce
animations.
These can be invaluble in grasping (and especially conveying) a geometrical concept.
Here's an example of a rendering from the OpenGL viewer for X-windows. The
objects shown are:
- CLAS :large blue ball
- tagger magnet : odd-shaped red object
- PrimEx dipole : purple box
- PrimEx target : red square just upstream of dipole
- PrimEx calorimeter "HYCAL" : grey box
The tagger magnet is a "SubtractionSolid" made from a tube section minus
a box. I do not know why there are remnants of the inner radius of the
tube section showing up as flaps underneath the tagger. I suspect it has
to do with the OpenGL driver making use of hardware accelration routines
that are sometimes buggy. I've seen similar effects in
other programs that use hardware
acceleration to draw solids.
There's not too much here right now, but I'm hoping to produce some high
quality images for PrimEx which can be used for presentations etc.
I also fully expect to actually use this for actual simulation, but that
will be phase 2 ...
David Lawrence
davidl@jlab.org
Thu Jan 11 16:07:19 EST 2001