Stereoscopic Viewing

This section provides background information about stereoscopic viewing.

Computer technology uses stereoscopic viewing to recreate the way we naturally see depth - stereoscopically. Stereoscopic viewing describes how we use both eyes, each with a slightly different perspective, to perceive depth in a physical environment. It delivers the most realistic visual representation possible of complex digital models, giving engineers, architects and scientists the best possible understanding of three-dimensional information, and yielding levels of technical proficiency not available using a typical 3D view.

These images can be perceived by a user wearing special glasses which continuously transmit separate images to the left and right eyes, creating a view of computer or video-based objects that have depth, perspective and presence in three-dimensional space.

We do not intend to describe here all the possible hardware configurations which support stereoscopic viewing for Version 5. Consider the examples of hardware configurations mentioned in this section as no more than that: just examples.

What Do You Need?

Stereoscopic viewing is possible on both entry-range and high-end configurations: you do not automatically need expensive equipment to enter the realm of stereoscopic viewing.

Entry-Range Configurations

On entry-range configurations, you need at least a graphics board supporting stereoscopic viewing on your platform, and a set of special glasses.

The CrystalEyes® range of glasses (designed by StereoGraphics, Inc.) is an example of the type of special glasses supported allowing you to benefit from stereoscopic viewing capabilities.

Many graphics boards are supported. For detailed information about supported hardware configurations if you are running Windows, and general information about StereoGraphics, Inc. products, browse the following Internet site:

http://www.reald-corporate.com/scientific/products.asp

  In case you want to use a standard computer with only one graphic board, two video inputs (one per eye) are required to manage a stereoscopic display system. If you have a computer with only one graphic board providing a single video output, the Cyviz XPO2 is a solution.

The Cyviz XPO2 is a small electronic box converting one active stereo video input into the two corresponding plain video outputs (one per eye). A typical application would be a projection wall with passive stereo (two projectors) or a head mounted display:

 

For detailed information about XPO2, please browse the following internet site :

http://www.cyviz.com

High-End Configurations

High-end configurations typically involve not only specific graphics boards and special glasses, but also a whole range of high-quality, immersive, stereoscopic display platforms from vendors such as FakeSpace Systems, which allow you to manipulate, assemble, and disassemble virtual mechanical objects while navigating through the entire digital mock-up.

For detailed information about supported hardware configurations, and general information about FakeSpace Systems products, browse the following Internet site:

http://www.fakespacesystems.com/

http://www.barco.com/projection_systems/

How to setup stereoscopic viewing in Version 5?

This section is dedicated to stereoscopic viewing on systems that use one graphic board supporting OpenGL quad buffered stereo.
  1. Set up the appropriate hardware configuration.

  2. Set up the graphic adaptor configuration for stereoscopic display.

    This step depends on hardware and operating system configuration. Some systems require administrator privileges to change the graphic adaptor display mode.

    You are required to determine the height, width and frequency characteristics of the graphic interface.

    On Solaris:

    On Solaris 8 use the fbconfig command, first to know the available configurations: 

    $ /usr/sbin/fbconfig -res ?

    Choose a configuration, for instance 1280x1024x114s, then use the fbconfig command once again:

    $ /usr/sbin/fbconfig -res 1280x1024x114s

    Logout to restart the X server.

    On previous Solaris versions, the configuration command may depend on the kind of graphic adaptor you have: ffbconfig for Creator 3D, afbconfig for Elite and SUNWifb_config for Expert 3D.

    On AIX:

    On AIX systems, you can use the smit utility:

    • log as root
    • run smit
    • choose "Devices"
    • choose "Graphic Displays"
    • choose "Select the Display and Resolution refresh Rates", then the correct graphic board if more than one are on the system
    • choose a stereo visual. The "list" button provides a list of all available graphic modes. Stereo modes are at 120Hz, for instance 1024x768@120Hz.
    On HP-UX:

    With root privilege, use the setmon command to know the available configurations: 

    $ /opt/graphics/common/bin/setmon -r

    This gives a table on which each line corresponds to an available graphic mode. To choose a graphic mode, type:

    $ /opt/graphics/common/bin/setmon -s n

    where "n" is the entry number of the chosen graphic mode.

    To avoid a bad colormap effect between CATIA V4 and CATIA V5, some modifications need to be done in the X server file as explained below:

    First, logon as "super user". Then,

    create:

    mkdir -p /etc/dt/config

    copy:

    cp /usr/dt/config/Xservers /etc/dt/config/Xservers

    edit:

    /etc/dt/config/Xservers

    at the end of the line beginning with ":0 Local", add:

    (on Solaris)  "-dev /dev/fbs/ifb0 defdepth 24 defclass TrueColor"

    (on AIX)  "-d24 -classTrueColor"

    Then, restart the X server.

    On Windows based platforms

    Stereo activation can be found in "Display properties" (select the "properties" contextual command in your desktop background). Depending on the graphic adaptor, you may need to have administrator privilege to access the stereo setting. 
    The location of this setting varies depending on the graphic driver vendor. If it is not directly available in the vendor. If it is not directly available in the vendor tab page, look for "advanced configuration" in the vendor tab page or in the "settings" tab page. In some cases, you may need to reboot the computer to activate the new mode.

  3. Start a session.

  4. Select Tools > Options > General > Display > Visualization.

  5. Click the Devices tab, and click On next to Stereo option to enable stereoscopic viewing.

    Note the following platform-specific restrictions when enabling stereoscopic viewing:
    • on AIX: you lose colors by passing from 24-bit to  12-bit colors using the GXT800 graphics board.
  6. Exit your session to save your settings, then restart.

  7. Display the Stereoscopic Viewing dialog box as follows:

    • enter the following command in the power input field:

    c:Stereoscopic

    • or, select Tools > Customize, click the Commands tab, select All commands from the "Categories" list, then click Stereoscopic. You can then add the command to a toolbar for easy access as explained in "Customizing a Toolbar by Dragging and Dropping" in the Infrastructure User's Guide. Select the command once it has been moved to the toolbar
    • or select View > Commands List then click Stereoscopic.

    The Stereoscopic Viewing dialog box looks like this:

    By default, stereoscopic viewing is disabled (Off).
  8. Set the Stereo option to On to enable stereoscopic viewing.

    Note that visualization performance is impaired if select On.
  9. Set either Manual or Automatic mode.

    This mode sets the distance between your eyes when using stereoscopic viewing (to do so, enter the distance in the Viewpoint separation box).
    The default mode is Manual.
    Automatic mode

    When working in Examine mode, you should set the eye gap to Automatic. Use this setting if you are viewing an object that in real life you could reasonably manipulate using your hands. This setting is suitable for working in confined spaces requiring an accurate perception of depth, in which you focus on the rotation point.

    When automatic mode is active, the eye-distance is adjusted automatically depending on the zoom factor.

    In automatic mode, the line of sight converges on the focal point. If the focal point is far away, and objects are located before the focal point, these objects will be viewed in a fashion more precise than in real life, so viewing results are unrealistic in this case.

    Manual mode

    Manual mode provides you with precise control over the distance between your eyes, so that you can adapt your field of vision to the working context.

    The value you enter is in millimeters.

    This mode is particularly suitable for working in Walk or Fly mode, when working on large-scale assemblies or industrial plants requiring a wider field of vision. If you need to perceive a high degree of depth, you should set the distance between your eyes accordingly.

    In this mode, the line of sight is parallel.