Add export variable unit hints to Inspector

[ShawnHardern]

Describe the project you are working on

A game prototype that makes heavy use of the inspector in the godot editor.

Describe the problem or limitation you are having in your project

While prototyping a game, I often change various variables such as speeds, angles, pixel values, and other parameters directly in the Inspector to modify and fine-tune my game mechanics.

The Inspector allows me to quickly and easily adjustment these values during development, but a key limitation I encounter is the lack of clarity regarding the units of these variables.

Describe the feature / enhancement and how it helps to overcome the problem or limitation

I propose extending the existing PropertyHint system in Godot (both in GDScript and C#) to allow for an additional unit hint to be displayed next to exported variables in the Inspector. This unit hint would provide context about the expected units of measurement (e.g., m/s, px, deg) for specific variables, making it easier for developers to understand and adjust their values directly in the Inspector.

Describe how your proposal will work, with code, pseudo-code, mock-ups, and/or diagrams

I propose extending the existing PropertyHint system in Godot (both in GDScript and C#) to allow for an additional unit hint to be displayed next to exported variables in the Inspector. This unit hint would provide context about the expected units of measurement (e.g., m/s, px, deg) for specific variables, making it easier for developers to understand and adjust their values directly in the Inspector.

Possible Gdscript Example

@export_unit("px") var height

Possible C# Example

[Export(PropertyHint.Unit, "px")]
public int height{ get; set; }

Possible Screen Mockup #1

Possible Screen Mockup #2

If this enhancement will not be used often, can it be worked around with a few lines of script?

I don't believe there is currently a way to do this

Is there a reason why this should be core and not an add-on in the asset library?

It relates to how the core editor currently works

[AThousandShips]

Why would you need a separate unit displayed beyond the existing unit suffix? What is insufficient about using the existing suffix:px for example

[Castro1709]

I think maybe you are not aware of it but you can do that with the suffix hint like this:

@export_range(0, 100, 1.0, "suffix:px") var pixel_range : float = 80.0

[AThousandShips]

Or with @export_custom (not sure if there's a direct equivalent in C#, not familiar with exports there)

[ShawnHardern]

Hey @Castro1709 and @AThousandShips, 👋🏻

Thanks so much for bringing this to my attention 😄 . I was referring to the information available in GDScript exported properties docs and C# exported properties docs, but I didn’t come across this feature there.

I will investigate this further and will update the documentation to include this information if appropriate.

[ShawnHardern]

In case this helps anyone, I wanted to share that this feature indeed already exists! 🥳

Gdscript Example

@export_custom(PROPERTY_HINT_NONE, "suffix:m/s\u00b2") var gravity :float

C# Example

[Export(PropertyHint.None,"suffix:m/s\u00b2")]
private float _gravity = 9.8f;

In Inspector

[AThousandShips]

Closing as already implemented, thank you for your proposal nonetheless

[ShawnHardern]

Closing as already implemented, thank you for your proposal nonetheless

Thanks for your time @AThousandShips, I have created docs PR #9785 to surface this functionality better