Virtual Point 1

Notation Throughout the TWiki

Text type	Example	Meaning
Brown verbatim text	> source script.sh	Type the command into the shell prompt
Purple verbatim text	> TBrowser t	Type the command into the Athena/Python/ROOT prompt
Standard verbatim text	script.sh	Code snippets and file names
Green verbatim text	Output="Hello"	Run/job/script output
Blue verbatim text	Package-01-02-03	Package names
Italics	Terminus Technicus	Any term
Bold	important	Anything important within the text
Red bold text	VERY IMPORTANT	Anything deadly important
< Text within tags >	<Example>	Substitute for your concrete instance

Atlas VP1 is a 3D (Qt) event display for point 1: http://cern.ch/atlas-vp1

In order to run Virtual Point 1, you must have your Athena sourced (https://twiki.cern.ch/twiki/bin/view/Atlas/WorkBookSetAccount) and then just run

> vp1

VP1 can also be run directly on an ESD file like this, which loads all hits and tracks directly into geometry:

> vp1 <YOUR ESD.pool.root FILE>

1 Setup

Official Installation instructions: https://atlas-vp1.web.cern.ch/atlas-vp1/prerequisites.php

You can run VP1 in two ways:

1. Remotely: In order to run the program remotely, you need to use SSH connection with enabled X11 forwarding and have your X server running. Windows users use this procedure to run VP1: http://www-hep2.fzu.cz/twiki/bin/view/ATLAS/WindowsRelated
2. Locally: The other option is to deploy your local Athena distribution and run from it. It is well suggested, since 3D visualisation is very slow while running remotely.

Since VP1 is under constant development, you will want to keep your version up to date. The patch script can be found here: https://atlas-vp1.web.cern.ch/atlas-vp1/vp1patches/vp1-install-patch. You can run it from any directory on your AFS assuming you have provided the patch file from the bottom of this page: https://atlas-vp1.web.cern.ch/atlas-vp1/vp1patches.php

1.1 Running VP1 on new geometry

1) Execute:

> vp1 -detdescr=ATLAS-GEO-00-01-00 -nomuon -nocalo

2) Run tracking studies

3) Enter the Geo tab and turn on Pixel in Sub systems

4) Look into the Display Options and turn off some red circles in the Hide Sectors to see inside the detector

5) Write Air to the Vols. with mat, under Actions on visible volumes

6) Click Expand a few times and watch in awe.

2 Modification

2.1 Download and setup of necessary packages

To be able to modify the VP1, you need download all vp1 up to date packages. The instructions are here: https://atlas-vp1.web.cern.ch/atlas-vp1/usingpatchscript.php. But to keep it simple:

Get this file and run it: https://atlas-vp1.web.cern.ch/atlas-vp1/vp1patches/vp1patch_cvshead_checkoutandbuildall.x

>
  wget http://atlas-vp1.web.cern.ch/atlas-vp1/vp1patches/vp1patch_cvshead_checkoutandbuildall.x
  chmod +x vp1patch_cvshead_checkoutandbuildall.x
  ./vp1patch_cvshead_checkoutandbuildall.x
>

2.2 Colour scheme modification

To change the colouring of pixel modules, modify the contents of /graphics/VP1/VP1Systems/VP1GeometrySystems/src/VisAttributes.cxx file as follows:

{
   SoMaterial *m = new SoMaterial;
   m->diffuseColor.setValue (1, 0, 0);
   m->specularColor.setValue (1, 0, 0);
   m->emissiveColor.setValue (1, 0, 0);
   m->shininess.setValue(.60);
   add("pix::Hybrid",m);
}

Run VP1 on new geometry to see the change:

> vp1 -detdescr=ATLAS-GEO-00-01-00 -nomuon -nocalo

-- MartinZeman - 13 Aug 2008