CalVR

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Contents

Overview

This wiki page was created to give programmers an overview of how to use IVL's virtual reality visualization framework CalVR. Special emphasis is given to those programmers who already know how to write code for COVISE.

What is CalVR?

CalVR is a virtual reality framework which has been entirely developed in the Immersive Visualization Laboratory at Calit2. It is designed to be open source and royalty free. CalVR implements the typically used VR functionality of middleware such as CAVElib, COVISE, VRUI or FreeVR and adds to it by supporting nonstandard VR systems like autostereoscopic displays, as well as multi-user support for viewing and interaction. CalVR is entirely object oriented and written in C++. Functionality can be added through a simple plug-in system which allows compiling new modules separately from the main code. CalVR has built-in navigation algorithms, a 3D menu system, support for a variety of 3D display and tracking systems, as well as support for collaborative work at different sites. The campus wide visibility of Calit2’s Immersive Visualization Laboratory (IVL) has allowed the group to engage in a large variety of software application research and development with groups from many of UCSD’s departments. The experience from more than six years of campus-wide collaborations and many publications reporting on those projects both in the virtual reality community and also the domain sciences is flowing into the design and development of the CalVR software framework.

CalVR Specs

  1. Operating system: CentOS 5 Linux, Mac OS X (experimental: only tested on 10.6.7.)
  2. Programming language: C++
  3. Graphics API: OpenSceneGraph
  4. Build system: CMake
  5. Tracking APIs supported: VRPN, TrackD
  6. PC cluster support
  7. Support for multi-screen virtual reality systems

Building CalVR

The project is built with cmake. At the moment, it is set to require at least version 2.8.

Dependencies

The major external libraries needed are:
OpenSceneGraph - version 3.0.1 is currently recommended.
MiniXML - 2.6

Building OSG

The latest release of OSG can be found here. (See above for suggested version)
Go to main OSG directory and type ccmake .
In CMAKE_BUILD_TYPE, press Enter to edit the field, type in one of the options that with debug information: RelWithDebInfo
On Mac OS X, set OSG_DEFAULT_IMAGE_PLUGIN_FOR_OSX to "imageio" and OSG_WINDOWING_SYSTEM to "Cocoa".
Press 'c' to configure, press 'g' to generate. and 'q' to quit. Now type make to build. Go get coffee.

OSG Extra Libraries

There are a number of extra libraries are optional, but can be built into osg to add additional functionality. This is done by building/installing the libraries then setting the include/library path values in the osg ccmake window. When all paths are added, configure, generate the makefiles, and compile.

Coin3d

Getting the Code

Calit2 Server

First you will need an account on the GIT server.

The repo is now split into two sections, one of the framework and another for the plugins.

Checkout the main framework from the repository:

 git clone vis2.calit2.net:/git/calvr CalVR

Checkout the plugins from the repository:

 git clone vis2.calit2.net:/git/calvr_plugins CVRPlugins

GitHub

The repo is now being cloned to github: https://github.com/CalVR
You can do a read only checkout by doing the following:

git clone git://github.com/CalVR/calvr.git CalVR
git clone git://github.com/CalVR/calvr_plugins.git CVRPlugins


Building Core

To help aid the cmake configure, you can optionally set environment variables for the location of these libraries:
OSG_HOME - location of OpenSceneGraph install, very good to set if cglx has a copy of osg in /usr/local
MXML_HOME - location of MiniXML install

Go to the project root and run

ccmake .

then type 'c' to configure.

If the configure doesn't find the core libraries, manually fill in the information. For OpenSceneGraph, fill in the OSG_HOME value and reconfigure. This should fill in the OSG_INCLUDE_DIR correctly. Note that this process also sets the library locations in hidden variables, so you can't just fill in the include directory manually.

There are also optional libraries that add additional fuctionality.
Interleaver - if present, builds the ability to create a screen for lenticular 3D rendering - TODO: upload src here

From the ccmake menu you can also select which plugins you want to build. Turn those plugins on and reconfigure. The configure will tell you if there are undetected additional libraries needed to build those plugins and the cmake variables for those libraries will now be in the main menu.

When you are done, select the option to generate and exit ccmake.

From here, run make.

Building Plugins

The plugins are built in a similar way. Go the the plugin root directory and run

ccmake .

The plugins also need OpenSceneGraph and this can be set the same way as above. The plugins need to know where the CalVR home directory is. This can either be manually set or it will look for the CALVR_HOME environment variable.

You can then toggle the plugins that you want to build on and reconfigure. If there plugins have any dependencies, they will appear in the cmake config.
Now generate and run make.

CalVR Configuration

Environment

Before runing CalVR you need to add the library directories into your LD_LIBRARY_PATH in .cshrc/.bashrc. On Mac OS X, set DYLD_LIBRARY_PATH.
These directories should include the ${CALVR_HOME}/lib directory and any lib directories for the CalVR dependencies (i.e. osg/mxml/etc)

Add an environment variable to .cshrc/.bashrc, for example:
.cshrc

setenv CALVR_HOME /home/calvr/CalVR/
setenv CALVR_CONFIG_FILE config.xml

.bashrc

export CALVR_HOME=/home/calvr/CalVR/
export CALVR_CONFIG_FILE=config.xml

Config File

Calvr uses an xml based configuration file.
For more infomation on the config file, see: CalVR Config File

Running CalVR

The main CalVR executable is ${CALVR_HOME}/bin/CalVR.

CalVR Application Development

Applications using the CalVR environment are developed in the form of CalVR Plugins.