Viewers

SG Toggle
 

SG Toggle is a simple Windows desktop accessory for enabling and disabling stereo  image viewing with SimulEyes™ glasses. SG Toggle is available for Windows 3.1 and Windows 95.

Each version of SG Toggle activates a SimulEyes Windows driver which sets the monitor into interlaced  video mode and paints the SimulEyes white line code at the bottom of the screen.  The white line code is used to trigger the shutters in SimulEyes.  The SimulEyes driver is called SVR3D.DLL for Windows 3.1 or SVR3D32.DLL for  Windows 95.  These drivers are included in the ZIP file with SG Toggle. Either of these DLL drivers must be present in the same working directory as SG Toggle  (or copied into the Windows System directory, C:\WINDOWS\SYSTEM).

The SimulEyes drivers for Windows currently work only for specific chipsets in 256-color modes of 800x600 or 1024x768 resolution. We support the most popular chipsets and continue to add support for other chipsets.  As this support is added, you need only replace your current DLL with the newer versions we will post. (In the future, VESA interlaced modes will become standardized as part of Windows.)

In the event that your video card is not yet supported by the SVR3D driver, SG Toggle will generate an error message.  However, in some cases, you may be able to manually set the video mode to interlaced through the Windows Control Panel under Display Settings. If this is the case, then SG Toggle can still be used to draw the SimulEyes white line code at the bottom of the display thus enabling stereo image viewing.

Interlaced mode works by first drawing the even-numbered scan lines (0, 2, 4 . . .) on the monitor, then returning to the top to draw the odd-numbered lines.  The method for viewing stereoscopic images in interlaced mode is to output left-eye images on the even-numbered scan lines, then the right-eye images on the odd-numbered scan lines.  In interlaced video mode, the left- and right-eye scan lines appear as complete video fields alternating left and right in sync with the SimulEyes' shutters.

When interlaced video mode is active, white line code also needs to be drawn at the bottom of the display. This white line code is the registration signal for shuttering SimulEyes in sync with left- and right-eye views. (Under Windows 95, if your taskbar is displayed at the bottom of the screen, you may need to move it to another side of the display.)

Stereo images are properly composited when the left-eye view begins as the first even scan line (or multiple of an even scan line). There is a 50/50 possibility for displaying  the composited stereo image improperly in a window on the desktop. That is, if the window is positioned or re-sized such that the left-eye information effectively begins on an odd scan line, then the stereo information will be inverted. This phenomenon, called "pseudo-stereo", may appear to contain depth but the observer will have a more difficult time perceiving depth, or not at all, and the overall perception won't be correct.

To remedy this problem, a registration test image is necessary to initially align a window on the desktop for use with SG Toggle.  We have included a test image called TEST.GIF for this purpose.

Sim Web 3D

Sim Web 3D is a java plug-in which automatically compensates for correct window positioning. In cases where the left-eye information starts on odd numbered lines instead of even, the white line code is reversed to match.  This keeps the overall stereo image in the correct viewing orientation.

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