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The top one is wrong because it violates the right hand rule.
Z should be inverted in the top picture.
Agreed. That would be totally valid.
go home programmer, math does not need you!
One of my friends and I used to always have this debate because of our different backgrounds. I got used to +Y being up because of doing physics for several years and seeing side-on diagrams that needed to account for gravity. My friend has a background in geology, so he’s used to top-down surveying maps where +Z is up. It all depends on your perspective.
But my way is right. We need to have standards, people.
I’m like your friend, but my perspective is from the atmospheric sciences. The z-axis is anything vertical.
I wonder if all earth sciences are like this?
Z is elevation. Any real world application, z goes up down. 3D applications SHOULD use it for elevation. I despise that many do not. It’s so fucking confusing. 2D, sure y go brrr. But once that 3rd dimension is added, y needs to take several seats and quit trying to take on dimensions it doesn’t have any right to.
Y-up sorta makes sense in games. Imagine a 2D platformer, Y is up and X is horizontal. Now add depth. Instead of flipping axis just use Z for depth.
That’s the core of my point though. Once you add depth it’s not 2d space anymore (even though the screen is 2d, the represented field is 3D) and y becomes depth.
It all depends how you perceive the XY plane. Like if your job involves blueprints than XY plane lies flat and horizontal then it makes sense that Z axis is height. Hence why engineering software is all Z-Up. If the XY plane is upright, like screen coordinates, then Z is depth. Hence why many software that is used to create content for the screen is Y-Up. Like Maya, Houdini, Unity, OpenGL etc.
It makes more sense if you’ve ever drawn in CAD. Top view, x and y. Now side view, y and z or y and x. You look down on x and y, and if you are extruding you now create the z axis dimensions. For the people who draft on the side axis: you are true psychos (ok, unless you’re using a lathe I suppose, or if the silhouette is more defined from the side… ok maybe not psycho, just odd)
User look sideways at item on shelf. Designers look down on paper. Both viewpoints are needed for it to be a good object.
Architects do both because they have all that math and something serious to prove.
I do use CAD software but always have my items resting on an x/y plane with z being height. I do some 3d printing and basic cad designs, so z being elevation still makes sense there.
Thanks to 3D printing Z is firmly “up” in my brain even if the modeler I use does it differently.
In my brain Z is Up, Z is Height. In my job I have to deal with both all the time which is quite annoying.
is it though when you look at a screen?
Yeah… As a Blender 3D artist, Z axis has been baked into my brain as the up/down axis.
“baked” pun intended maybe?
Always bake.
I’ve been making models in Blender to import into Godot so I have to constantly switch.
I have experienced this. It was pretty confusing at first.
In a 2D game Y is up. Going from 2D to 3D would make sense to add another dimension forward to account for depth.
However if you start with a map of a 3D surface then North is Y and East is X you’d add Z to account for elevation like everybody making maps would.
I guess it depends on how you look at it.
Yes, but please just make it follow the right hand rule…
Which one?
(Technically all the same, I know).
The first? I dont know… They all look weird since the finger axes dont intersect properly.
X is up, there now no one is happy.
Z is always depth. Both are correct but define different perspectives. Top is looking across the landscape from an arbitrary floating perspective, bottom is looking down with anchored mapping to the surface.
Smh I was fine with both. The upper one reminded me of the X Y axis we use to represent functions in maths. While the lower one represents altitude on a 3D map.
Invert y axis is the first option I tick in every game
Spent most my life working in a 3d environment… need to reverse that thing for a controller every single time
Good answer. Many posts are people saying “my approach is the right one, other people are irredeemable morons who should burn in hell”, but you’re right, it depends on your perspective.
The second fellow is a machinist, like me.
Yes! Except when using a lathe…
I mean a lathe doesn’t really have a y axis tho. Tool height is just tool height. Even on a vertical lathe you usually only have x and z.
Don’t forget the handedness of each coordinate system!
I’ll leave this here for context (bottom right is the only sane one)
Minecraft being the most influential of them all
Minecraft
Z is depth, full stop, and I have my fists raised, Queensbury-style, to anyone who contends otherwise.
My son and I have had this very argument. I think the top one is right as he thinks it’s the bottom one. I have a coding background and he has a 3D printing background. I figure that’s why we’re different but I know nothing about 3D printing beyond the cool stuff I see on the Internet and things he’s printed for me.
I have a looking-at-the-chalkboard-in-highschool background which I’m pretty sure defines my perspective(heh).
I have been coding for over 20 years and the bottom one is more correct to me.
X and Y need to be on the same plane.
