7 ms·

I think it's more than that. As Carmack observes, you don't see in 3D. You see two 2D planes that your brain extracts a certain amount of depth information from

by jerf 7y ago

I think it's more than that. As Carmack observes, you don't see in 3D. You see two 2D planes that your brain extracts a certain amount of depth information from. As a UI goes, you can't actually freely use that third dimension, because as soon as one element obscures another, either the front element is too opaque to see through, in which case the second might as well not be there, or the opacity is not 100% in which case it just gets confusing fast. You've really got something more like 2.1d to work with with humans; intefaces need to take that into account, and maybe sometimes use that .1d depth dimension to provide light hinting, but not depend on it. So you're not removing a dimension... you're acknowledging it doesn't exist. There isn't really a "third dimension" here to take advantage of. It may be visually impressive if something flies from far away to up close, but in interface terms, all that has happened is that the z-buffer values shifted, but the interface still has the same number of square radians available that it did before. The depth information is a lot more like an additional color than an additional spatial dimension. UIs are better with color hinting available when used well, but there's not much fundamental difference between a color 2D interface and a monochrome 2D interface. Proof that it isn't much is that there are some people who use settings to set their phone to monochrome, and the result is at worst occasionally inconvenient, not crippling. Compare with trying to go from a 2D interface to a 1D interface, which would be utterly crippling and destroy a huge swathe of current UI paradigms. To truly "see in 3D" would require a fourth-dimension perspective. A 4D person could use a 3D display arbitrarily, because they can freely see the entire 3D space, including seeing things inside opaque spheres, etc, just like we can look at a 2D display and see the inside of circles and boxes freely. They have access to all sorts of paradigms we don't, just like no 2D designer would ever come up with a "text box", even though it fits on the 2D plane, because no 2D user could see inside the text box to see what's in it. (This is one of those cases where the mere act of typing it out improved my understanding of the topic. I didn't have the "depth information is really just another color" idea going in, but the more I think about it the more sense it makes, in terms of the amount of information that channel can carry. Just like color, it's not quite 0, but you can't really stuff all that much in there.)

vbuwivbiu 7y ago
yes we see 2d surfaces in 3d. Dolphins can actually see in 3d as they can sense entire 3d volumes and project them back to eachother too.
- snazz 7y ago
  I’m assuming you meant “yes we see 3d surfaces in 2d” to be consistent with the parent comment? Also, I’m impressed that dolphins have that ability. How does projecting them to each other work biologically? Do they somehow encode what they see as sound (less lossily than humans do)?
  - taneq 7y ago
    I'd imagine they work directly in the frequency domain. They don't "see with sound", they'll just hear nested spheres or whatever.
    - all2 7y ago
      This suggests to me that humans could harness the same audio phenomena.
      - taneq 7y ago
        Some people can. There's a few cases of blind humans who can echolocate to some degree of accuracy (enough to ride a skateboard in one case).
DubiousPusher 7y ago
True, almost any interface that overlaps helpful data in layers or stacks is usually terrible. Hell, I don't even like desktop computer GUIs that allow you to have stacks of windows. I'd rather see one thing at a time and cycle between them. Or have a picker view. That said we do actually get quite a bit out of that ability to see depth. People who lose depth perception have quite a hard time adapting to the world. And our spatial understanding seems to go beyond our vision. That to me is where a 3D interface might be really powerful. Sometimes things which we struggle to decode in 2D are just intuitive in 3D like knots or the run of wires or pipes. As I said elsewhere in this thread I think the 3D interfaces that are really going to be powerful haven't occurred to us yet. And I believe that what we'll find in time is that there are things which 3D interfaces are tremendously advantagous for and using anything else will feel like a hinderance. But those will be things for which 2D interfaces don't already do an amazing job.

by jerf 7y ago

vbuwivbiu 7y ago

yes we see 2d surfaces in 3d. Dolphins can actually see in 3d as they can sense entire 3d volumes and project them back to eachother too.

snazz 7y ago
I’m assuming you meant “yes we see 3d surfaces in 2d” to be consistent with the parent comment? Also, I’m impressed that dolphins have that ability. How does projecting them to each other work biologically? Do they somehow encode what they see as sound (less lossily than humans do)?
- taneq 7y ago
  I'd imagine they work directly in the frequency domain. They don't "see with sound", they'll just hear nested spheres or whatever.
  - all2 7y ago
    This suggests to me that humans could harness the same audio phenomena.
    - taneq 7y ago
      Some people can. There's a few cases of blind humans who can echolocate to some degree of accuracy (enough to ride a skateboard in one case).

DubiousPusher 7y ago

True, almost any interface that overlaps helpful data in layers or stacks is usually terrible. Hell, I don't even like desktop computer GUIs that allow you to have stacks of windows. I'd rather see one thing at a time and cycle between them. Or have a picker view. That said we do actually get quite a bit out of that ability to see depth. People who lose depth perception have quite a hard time adapting to the world. And our spatial understanding seems to go beyond our vision. That to me is where a 3D interface might be really powerful. Sometimes things which we struggle to decode in 2D are just intuitive in 3D like knots or the run of wires or pipes. As I said elsewhere in this thread I think the 3D interfaces that are really going to be powerful haven't occurred to us yet. And I believe that what we'll find in time is that there are things which 3D interfaces are tremendously advantagous for and using anything else will feel like a hinderance. But those will be things for which 2D interfaces don't already do an amazing job.