Message: problems with BREPS Not Logged In (login)
 Next-in-Thread Next-in-Thread
 Next-in-Forum Next-in-Forum

Question problems with BREPS 

Forum: Geometry
Date: 12 Mar, 2012
From: Nika Valencic <Nika Valencic>

Dear Geanters,

I have a couple of questions concerning BREP Solids construction.

Browsing through the forum and User Manuals I saw several warnings that BREPS are not fully implemented. I managed to construct a solid using G4BREPSolidPolyhedra and it worked. However, when I tried to construct a G4BREPSolidCylinder and visualize it I got a cube(?!) (the code is attached bellow).

My first question: Am I doing something wrong? Is the problem only in visualization (I use Qt) or is just that this class is not implemented completely?

My second question: I want to construct a body that looks like a trapezoid, but with two circular edges and two straight but nonparallel edges, of thickness z (figure is attached bellow) . So far I successfully constructed (approximation) of this body, using G4ExtrudedSolid. Now I want to construct the body with actual circular edges. I see two options; BREPS or boolean solids. Which method needs more CPU time? I really want to try and build this body using BREPS. Can this be done? I tried defining all the surfaces that confine this body (planes + cylindrical surfaces) but failed. Can you give me some advice where can I look for examples of BREP construction and if this is possible?

My third question: When I visualize the body made by G4ExtrudedSolid I get some lines inside the body (figure attached bellow). I know this is just a consequence of visualization, but I was wondering if there is a way to get rid of them. I tried with /vis/viewer/set/edge and /vis/viewer/set/hiddenEdge commands but the lines are always present. Even if I draw this body as solid (/vis/viewer/set/style solid). Can you give me some advice how to make these lines invisible?

Thank you! :)


P.S: I'm using Geant4.9.5 on mac OS X (10.7.2).


Inline Depth:
 1 1
 All All
Outline Depth:
 1 1
 2 2
 All All
Add message: (add)

1 None: Re: problems with BREPS   (John Allison - 13 Mar, 2012)
2 More: Re: problems with BREPS   (Gabriele Cosmo - 13 Mar, 2012)
3 None: Re: problems with BREPS   (Nika Valencic - 13 Mar, 2012)
1 None: Re: problems with BREPS   (John Allison - 13 Mar, 2012)
(_ More: Re: problems with BREPS   (Gabriele Cosmo - 13 Mar, 2012)
 Add Message Add Message
to: "problems with BREPS"

 Subscribe Subscribe

This site runs SLAC HyperNews version 1.11-slac-98, derived from the original HyperNews

[ Geant 4 Home | Geant 4 HyperNews | Search | Request New Forum | Feedback ]