Z should be up

Which is what we're introduced to first, thus y and x are already established so z introduces the new dimension. It would seem counter productive in a math course to establish y and x and then introduce z as y and redefine y.

 

Unity3D : Left Hand Rule.

Vector3s work on Y = height X = width Z = depth

You'r index finger Y your thumb X yout middle finger pointing out Z

 

watch the dan video

 

I don't dabble in 3d much... is there anything keeping you from rotating the camera on the x axis and changing the gravity vector?

 

I tried this while making a little game of the Cube movie series. Changing gravity and rotating the camera works fine, but then your inputs go a little crazy.

 

I never heard of that lol. sounds like a cool movie

 

I think the earliest uses for 3D graphics were in film production where the visual plane is a vertical screen (x horiizontal, y vertical) and the third dimension denoted how far in front of or behind that plane some other object was. Z depth.

In other contexts such as architecture x is length, y is width (both horizontal), and z is height (ie up). Rhino uses z = up. So does Vue. I think the film convention became entrenched with Maya and other Autodesk products

 

CORRECT!

 

Oh. Just make sure you watch it correctly, the order of the movies is 3, 1, 2. It's one of my favorite movie series

 

Having programmed for decades I've gotten used to various swizzles in this case, and I don't give a damn which way is up, or the sign.

 

Oh really? What happens?

 

Wow, this is a debate about nothing at all. This argument is about as useless as debating feet and inches versus metres and centimetres. Coordinate systems are completely arbitrary mathematical constructs.

I've come across the following used to describe an R3 space.

• xyz
• ijk
• tuv

Then as soon as you break from R3 none of these work anymore. xyz is pretty bad, you've instantly run out of alphabet.

Maybe its just my engineering background. But I'm surprised this bothers anyone at all. There are so many competing conventions for everything out there. trying to standardise is difficult to impossible.

Everyone should be happy working in N-space dimension too!

 

There is no right answer.
I don't know why you guys are arguing over an arbitrary axis.

I also found this
"I think the direction of the coordinate axes are holdovers from different domains where the crucial plane was different, and X/Y were aligned with that crucial plane. In some applications the ground plane was the most important, thus X/Y were the ground and Z ended up perpendicular to that. For games however the crucial plane is usually the screen (especially of course back when they were 2D and just starting to transition to 3D) thus X/Y were the screen and then when games went 3D Z ended up perpendicular to that.

You can see that kind of distinction between the two biggest 3D art tools: 3ds max and Maya. The Z axis is up in 3ds max because that grew out of architectural tools, while the Y axis is up in Maya because that grew out of movie-making tools.

The important thing to realize when comparing any specific tool to what you learned in school is that it's all arbitrary. It really doesn't matter which way the axes are pointed as long as you keep everything consistent and translate correctly between different coordinate systems."

- http://gamedev.stackexchange.com/questions/46225/why-is-y-up-in-many-games

 

You know how when you look up or down but look left, the left is always the same? That's from using particular axis being mapped to your controls. You can't use local space or your rotation on 1 axis will affect the rotation on your next axis.

With that in mind, rotating the camera on 1 axis to make it appear up with gravity kinda... it worked, but it's not what you want lol. Looking 'up' appeared to look right, fun stuff like that. Movement was better because I use the body direction for inputs, but with that wonky look, I gave up on it.

 

I see. Thanks for the explanation.

 

Z is up only for architects and engineers.. for artists.. Z is depth.

just sayin'.

 

It was also unfeasible to rotate the world for what I was doing. You can toss objects into other rooms and see them take on the new gravity of that room

That explains the name for zbrush

 

Some engineers. Chemical engineers are reluctant to associate any dimension with something as crass as height or width. That so mechanical.

Actually I should ask my mechanical how they do it. I'm pretty sure they do y as height as well. It might only be the civil guys that use z as height.

 

Coordinate systems, just like scales are arbitrary in 3D space. You have to define them for them to have meaning, thus the confusion and differences between applications that tend to use defaults to help you define them. Afaik they all allow you to change that as well.

 

When I did my higher level math, y was up in 3d and z was depth, because it's an easier model to understand going from 2d coordinates, but they really do not matter, its just a matter of preference.

 

ya, I'm fairly sure of it... My reasoning for this is that when I took drafting (ages ago), our surface plane was horizontal (drafting table), and any elevations (depth) came up from the surface. Cross-sections would be made on separate drawings to make elevation drawings.

While in art class, we would represent depth on a surface plane through light and dark (dark being closer, light being further away) to get the appearance of depth (Z plane) on our horizontal surface. Painters also work on a vertical surface, where horizontal and vertical (left right, up down) and depth again is represented through light and dark (into the canvas, or away from the viewer)... same goes for sculpture.

anyway, that's how I know if a person is a "mechanical" thinker or a "creative" thinker... how they describe the Z plane.

 

Dogs can't look up.

 

Y?

 

Up is whichever direction a particular axis system says it is.

Its your job to deal with it.

 

Thats an Australian breed so its actually looking down.

 

On my screen, the up is the direction where Eric's dog is watching. As the heads of humans are supposed to be on top of the body, I have to ask you to rotate your avatar picture to look in that direction as well, because you are violating the laws I have on my computer screen. Thank you!

 

But you're upside down...or are you?

 

Change your monitor settings to Landscape (flipped) to resolve.

This won't actually resolve the problem, but it seems that it would make the dog the offending party instead of me. Which is good for me.

 

I like that Y is up.

If you do any type of math, x is left-right, y is up-down, and z is 3 dementional

 

I actually would like to have a 4D coordinate system implemented into Unity6. And it should be based upon a right-foot-left-eye coordinate system.

In all seriousness, though: All the 3D Appls I've been using either had Y-Up as a default or gave the option to determine which axis should be up. Modo for example could even use X-Up in theory but the default is Y-Up as well. I am one of those guys who is annoyed by Z-Up applications.

This should be a thing in every 3D modeler, IMO:

 

I'm afraid you're going to need to direct future complaints to the Dog.

[SOLVED]

 

I have been waiting for this opportunity. I don't mind y being up, but left handed bugs me big time!

 

its just weird... Z is up since kindergarten it seems..

 

Sorry if you mentioned it already, but if Z is up, what letter labels your forward axis?

I know a photoshopped image when I see one. We all know this isn't actually possible.

 

Y
X and Y is on graphs on paper, paper lays on a table or on the ground

the thing about the dog just further enforces X and Y being length and width..

cause we walk upon 2 dimension most commonly perceived,
so it is the first 2 dimensions ... height is the 3rd , Z is 3rd alphabetically..

.... ugh... whys this bug me soo much... >< .. i guess i just wanna be right, and its WEEEEIRRRDD people thought Y is up on a 2d graph...
i guess i forgot you guys probably younger and were taught with that new school curriculum thats known to be weirdly stupid ???

 

its just oddly "fun" to debate worthless crap hahaha

 

I live on a mountain. I experience the third dimension quite frequently.

 

Or funnily odd?

 

N E S W

and then ... altitude

 

I'm a quaternion person so I think W should be up.

 

No, silly, it's a 3D rendering. It took me weeks to model that.

You've never heard of "whiteboards"? Also, even when talking about paper lying flat, you're looking down at it, so the top of the paper is at the top of your vision, and you relate to it as being essentially vertical. Note how you say "top of the page", not "far end of the page".

Because you're really, really, really, really, really wrong, and it's tearing you apart.

--Eric

 

pft whatever

whiteboards werent invented until late 1950s

... yeah its just arbitrary.... its just weird... you guys perceived Y to be up on paper graphs? .. or whiteboard graphs... thats just weird


LOL thats funny about "top of the page" .. yeah thats weird, it really should be "far end of the page" ... i guess the problem is "mob perception" .. and us an individuals accepting the incorrect "mob perspective"..

good things to learn from all things.. funny, i was doubting the value of this conversation... not that i hadnt realized such things before, but its good to be reminded

.. i mean the saying "top of page" is a phrase learned from others speech, it was not learned from actual perception of facts.

 

Trace the x and y on a piece of paper, now put that paper on the screen with Unity in 2D mode. You should see that they point to the same direction, what you was doing wrong is how you use your screen, you need to put your screen flat on your desk like you do with your paper and everything will be fine!

Seriously, a coordinate system is not based on how you place a piece of paper on a table... If maths were done like that i don't think any science would have gone very far. You need to abstract yourself from any real world representation, XYZ or whatever you named your axis doesn't have to represent anything real (width, height, depth, altitude, forward, ...) When someone told you Z is up or Y is up, it was to help you understand how coordinates systems works because it's difficult for childs to abstract things like that. Then axis can represent anything, have n-dimensions and don't even have to be perpendicular...

 

People drew and painted vertically long before then.

Nope, that would be wrong. I mean really wrong. You have a totally bizarre way of viewing the world, I must say.

--Eric

 

So... y was forward because it lie flat on a surface? So relative to you, y was forward. Relative to the paper, y is up. Now we have computers and software that face you / stand up. Their relative up is still y, but now the plane is rotated on its x axis. Consider how the plane feels, man!

That is worthy of flabbergastation.

 

Yep for normal people, they think of Y being up as seen on a graph, and not as a flat piece in 2D space, with Z extending in the extra dimension. Its too late for unity to change it now anyway, I would like them to rename the axises to roll pitch and yaw, its much more intuitive then XYZ axis of rotation. It isn't going to happen though.

 

Makes me want to make a plugin haha.

 

Could you not just alter the unityengine.dll and change the front facing name of it?