View Full Version : Stereo viewing (true 3D) in Modeler!

Gavin Scott
02-08-2004, 04:14 PM
Here's a way to view your models in true stereo 3D from within Modeler without plugins, exotic 3D display hardware, colored glasses, etc.

Note: The following technique makes use of the common cross-eyed method of viewing 3D stereo pairs, similar to that used to view those "magic eye" type of 3D pictures. If you suffer from any seizure involving condition (epilepsy, etc.), are subject to migraine headaches, etc. then you probably shouldn't try this.

By using two "perspective" display viewports you can make a stereo pair that can be seen using cross-eyed viewing (similar to those "magic eye" things).

Start Modeler using the default four-viewport setup, and maximize modeler so it fills the screen.

Use 'd' to bring up the display properties. On the viewports tab, change the TL (Top Left) viewport to Perspective view type, and check "independent center". Verify that "independent rotation is *not* checked.

Change the TR (Top Right) viewport to the same settings (perspective, independent center, not-independent rotation).

Now load an object (a head is a good thing to start with).

You should have identical displays of the object in the TL and TR viewports at this point.

Using the "cross" widget in each perspecive vewport, move the image in the TL viewport slightly to the left and move the TR view slightly to the right. You'll see the perspective shift (the image will rotate slightly away from you) as you do it. The amount of shift required will depend on the simulated distance from your eyes to the object. If in doubt start small and work up. For a head you'll need a bit more than for an object like a jumbo jet where you'll only want a very small shift since the object is "far away".

Now you're ready to see in 3D.

To do this, you need to get your right eye to look at the left image and your left eye to look at the right image by crossing your eyes. (It's probably possible to do this the opposite way where instead of crossing your eyes you look straight ahead to infinity, but I find the cross-eyed technique easier; if you want to try the other way then you'll need to shift the perspective windows in the opposite directions).

Here's how to more easily do the eye-crossing thing. Sit about two feet back (for a 21" display, less for smaller ones). Hold a finger up in front of your eyes (about five inces from your nose) and focus on the tip of your finger.

This will naturally cross your eyes and you'll notice while doing this that in the background the two images have mostly come together on the display. Now you just have to relax your eyes (you can move your finger out of the way when you start to get it) and let the two images merge (they will start out fuzzy) then once the two images lock up you should be able to get your eyes to focus on the image while remaining crossed and you'll have a sharp 3D image of your model floating in space in front of you.

It can be difficult at first (your brain will fight you by insisting on trying to focus up close since your eyes are crossed so just try to relax your eyes) but most people can get it within a minute or so (though some people never seem to be able to do it). Once you get the idea you'll find that you can do it relatively quickly.

Since independent rotation is not enabled, you can use the rotation gizmo on one of the perspective windows to rotate the 3D view around while you're looking at it! You may have to make small motions so that the window you're rotating doesn't get too far ahead of the redraw of the other one if you have a slow video

Be sure to stop before you give yourself a headache, or start to feel ill or dizzy (anyone else make themselves sick the first time they played "Doom" or a similar FPS game?). If you can't get it, give up for a while and try it later. Remember that some people never seem to "get" this kind of stereo viewing thing.


02-08-2004, 04:27 PM
Warning: this method of stereo viewing may cause sufferers of migraine, epilepsy and Turette's syndrome to experience rapid uncontrollable convulsions.

02-08-2004, 05:23 PM
as if my eyes didn't hurt enough from staring at these screens all day already. I's quite impressive to see your model in realy-o truly-o 3d, but your co-workers might think it a bit strange when you start staring at the screen cross eyed.

02-08-2004, 06:12 PM
thats cool, too bad I want to puke!