Why is the Y-Axis negative moving 'up'?

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Why is the Y-Axis negative moving 'up'?

McSamwich

I come from Unity so I get there are discrepancies between different pieces of software. Such as that blender uses z-axis as up down in 3d and Maya doing its own thing. There is no universal standard, thats for sure. But man...Im enjoying the heck out of my time in Godot with its iteration speed, and alot of other perks but one thing that is bugging me is the inverted axis coming from Unity. I could totally get over just a different letter being in place of an axis, such as switching the z for y or whatnot. But an inverted axis really messes with me.

Does anyone actually find the above intuitive? I get theres a history and each software gets to choose its own path, but......

cybereality

If you mean for 2D, then Y moving down on the screen is the standard. It's been this way since probably back in the Atari days. This is because the older TVs uses CRT technology and the "beam" scanned from top to bottom, meaning 0 was the top of the screen. I never used Unity for 2D, but every other engine that I recall does this. For 3D, Y is up in Godot.

Pixophir

Yep, we must distinguish between 2D and 3D. In 2D, having 0,0 in the upper left in a game engine and counting by pixels to the right and down makes positioning things more intuitive. That's an abstraction by the engine. APIs handle that differently.

Same in 3D, there's a depth range, and world coordinates, which are transformed by a set of matrices to fit into the NDCs of the API. But I am not sure if you usually bother with these things (for instance whether depth range is 0..1 or -1..1 or the handedness of the coordinate system) when working with the editor, as you don't build your own viewports or matrices, the engine abstracts that away.
That's why I am bit confused about the -y up thing. That can happen when look-at-matrix- or viewport-parameters have been mixed up.

McSamwich

I see. Thanks for the replies. I will get used to it I guess. Its just frustrating to see so many different variations personally when trying different tools. Vectors are like the basics of working in an engine and I wish there was some standardization but there are reasons I guess...Well onto learn some more, peace

Lethn

McSamwich writing as somebody who has come over from Unity as well earlier on, your best move is to stop trying to compare Unity to Godot otherwise you'll hurt your brain because I went through the same thing. There are some very occasional similarities but as you're discovering the hierarchy setup, nodes and interface as well as how GDScript works are all very very different, treat this like you're coming at some brand new software you know nothing about.

McSamwich

Lethn There is a saying we have nowadays that one of the best ways to learn is 'to forget'. I think this is a perfect example. Yea I will try my best

cybereality

You can read how CRT displays worked here:

https://en.wikipedia.org/wiki/Analog_television#Displaying_an_image

The next question is, why were they designed that way? Probably because that is how the English language (and most other Romance languages) are written, so it was natural for the engineers to think in the left-to-right, top-to-bottom, design.