WHATIF and Linux

Michael Pachta-Nick mipani at gmx.de
Tue Sep 4 06:54:06 EST 2001

On Tue, 04 Sep 2001 09:28:40 +0100, Simon Andrews wrote:

Hi Simon, thank you very much for answering.

>The main thing to consider is what kind of stereo you're trying to get,
>there are two kinds above-below (also called interlaced), and frame
>sequential stereo.

I thought that there's a difference between above/below and
interlace, because the WhatIf manual sharply distinguishes between
the two modes.  The WhatIf manual says concerning interlaced vs.
above/below (chapter

Actually we have started first programming this "above/below" format
for the use of sync doublers, but later we came to the conclusion
that the solution of stereo in a window was much better, and we
decided to implement that one [interlace stereo] in our final

That seems to mean that WhatIf does not support above/below stereo
and thus a sync doubler would be useless. Did I get that right? Or
can I get the stereo effect without any special support by the
software I use?

>Above-below stereo should work on pretty much any hardware, 

But it must be supported by the software, right?

>it doesn't
>require a fancy graphics card, but it does require an external box
>called a sync-doubler. This should have been provided along with your
>shutter glasses.  

Unfortunatly not. But if it would help, we'll buy it.

>In your case you say you are plugging the glasses
>straight into the card - this would be right for frame sequential
>stereo, but you may need to buy an external sync doubler to go between
>the glasses and the card for use under Linux.  

Actually the shutter glasses are wireless. An infrared LED emitter is
connected to the graphics card. But that should be the same as
attaching a pair of wired glasses to the card.

We have two Linux PCs, one with a Elsa Gloria XXL (3DLabs Glint MX
chipset) which has also a 3pin Mini DIN socket to attach the emitter
to. The other PC has a Elsa Gladiac Ultra (NVidia GeForce2 Ultra
chipset) card, lacking a 3pin socket. For this PC we have a so called
Y-shaped cable, providing both a monitor socket and a 3pin DIN

[explanation about above/below snipped]

When switching to stereo mode within WhatIf it draws two images of a
molecule which are slightly shifted against each other. This is not
what can be considered as above/below, if I got you right. So a sync
doubler finally won't help, will it?

>Then we
>just have to convince manufacturers to start writing decent Linux
>drivers for their cards and everyone will be happy!

This will do if one manufacturer starts doing that and many Linux
user then buy their cards. Then other manufacturers will follow. The
manufacturers are still showing ignorance against the Linux
community. As long as 95%+ are using MS Windows they will not change
their behaviour, I fear.

>PS Seeing as you already have the card, have you tried running Swiss
>PDB Viewer under windows in frame sequential stereo?  That should
>work like a charm.

No, but I could give it a try.

Thanks a lot for your advice.


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