Godot-proposals: Add Blender-inspired UI and shortcuts for transform tools in 3D editor

[rcorre]

Describe the project you are working on:

FPS, but applies to almost any 3D project.

Describe the problem or limitation you are having in your project:

I find blenders UI for transforms to be very intuitive, fast, and accurate, specifically the following behavior:

• Pressing g/r/s immediately enters grab(translate)/rotate/scale mode for the selected object(s),
  and translation is performed until you confirm or cancel (no need to hold a mouse button)
  Click confirms, ESC cancels (restoring the original transforms).
• Pressing (shift)+x/y/z locks the transform to the specified axis/plane
• Pressing xx/yy/zz locks the transform to the specified _local_ axis
• Hold ctrl to snap, shift for precise movement

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

Implement the above features in Godot's 3D editor.
This is a revival of https://github.com/godotengine/godot/issues/19186.

Describe how your proposal will work, with code, pseudocode, mockups, and/or diagrams:

I think this can be broken up into several chunks. Maybe we don't take all of them, but some are low-hanging fruit that I think will provide a lot of benefit with little complexity:

• [x] Pressing (shift)+X/Y/Z locks the transform to an axis/plane while using a transform tool. Only process these keys while using a transform tool _and_ the mouse is down.
  
  
  
  • These are configurable editor shortcuts, so you could swap z/y for a more blenderlike experience
  
  
  • Implemented at https://github.com/rcorre/godot/commit/27b66ae52258c507253e4a04fa27a3634792713f
  
  
• [x] Pressing XX/YY/ZZ locks the transform to a _local_ axis. Godot has local transforms already, maybe we can just toggle the setting for the duration of the transform.
  
  
  
  • Implemented in https://github.com/rcorre/godot/commit/4bb6738a13858dee3fb75a17fd0aaf82dd796532
  
  
• [ ] Hold shift for precision. Shift is already used to disable proportional scaling in planar mode :confounded:
  
  
  
  • Actually SHIFT already works while snapping
  
  
• [x] _Optional_ bindings to activate a transform tool and use it without holding down the mouse (like blender's G/R/S)
  
  
  
  • Implemented at https://github.com/rcorre/godot/commit/7eac239471bb7a760d0f315452d0371099d0a9bc
  
  
• [x] Pressing ESC while using a transform tool undoes a transform
  
  
  
  • Implemented at https://github.com/rcorre/godot/commit/0a567528855a702d53fa2c2541176fb7ce7c8196
  
  
• [x] Highlight the transformation axis in the spatial gizmo. PoC here.

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

See the addon below. It isn't horrible, but it isn't "a few lines" either.

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

I actually started work on an addon to do exactly this.
It is still a PoC but demonstrates much of the functionality I describe above.
However, I was looking through the Godot source and realized that most of this is already implemented.
For example, you can already cycle through axis locks by pressing the middle-mouse button while holding down the left-mouse button.
However, this is clumsy and hard to discover (I didn't realize it existed until I saw it in the source).

So this could be implemented as a plugin, but I got tired of re-implementing Godot's editor logic and decided to try patching the editor instead.

[rcorre]

I also realize most of the feedback on https://github.com/godotengine/godot/issues/19186 was negative. I'm suggesting this because:

1. I actually _really_ like these aspects of Blender's UI and miss them a lot in Godot.
2. I think these features can be invisible and unintrusive to anyone who doesn't like them.

[Calinou]

@rcorre I definitely approve of having Vim-like shortcuts in the 3D editor. It's one of the cases where I actually managed to stick to Vim-like shortcuts (unlike actual text editing).

[Jummit]

I know some FOSS users coming from Blender to Godot who are used to the highly efficient keyboard shortcuts of Blender and would greatly appreciate something similar in Godot.
I think in this case both built-in and an addon would work.

[jonbonazza]

Im not very experienced in blender, but i agree having better shortcuts when working in the 3d editor would be very much appreciated. It's a pain currently to modify transform properties of 3d objects since you have to go back and firth between clicking the gizmo buttons way in the upper left of viewport and clicking objects in the viewport, wgich are usually very far away from the gizmo buttons.

[rcorre]

I've implemented all of this (except shift-for precision*) on 3.2.2-stable over here. I'm happy to port to 4.0 if there's an interest.

* shift-for-precision is tricky as the current code doesn't accumulate motion, it just compares the current mouse position to the position when you started the transform. This means holding shift will suddenly reset your transform to an earlier point (rather than just adding smaller increments to the current amount, as blender does). I didn't think this was useful enough to significantly change the current transform code (espeicially since shift already works for snap mode, enabling smaller snap increments).

[SecretPanda420]

@rcorre Another great addition can be improving the numpad controls in the editor inspired from Blender. As of now Godot only uses nkeys 7, 1, 3 for changing between top, front and side view and nkey 5 for toggling between perspective and orthogonal view. Keys 2, 6, 4 and 8 can be used to change view 15 degrees around in respective directions like in Blender and nkey 9 can be used to change view angle 180 degrees. As of now Godot only supports changing views using Alt + <N7,N1,N3> which can be a little tedious while working when other nkeys are just there serving no purpose when they actually can.

This is just a suggestion to improve this GIP. :)

[rcorre]

Thanks @SecretPanda420! I don't think I've ever used 2/4/6/8 in Blender, but maybe I should try :laughing:
I'll see if it is easy enough to implement, it sounds like it should be

[Calinou]

Keys 2, 6, 4 and 8 can be used to change view 45 degrees around in respective directions like in Blender

I support this idea, but I remember these hotkeys working by 15-degree increments, not 45-degree increments. (I just tested it in Blender 2.83.3; it takes 6 key presses to rotate by 90 degrees.)

[SecretPanda420]

I support this idea, but I remember these hotkeys working by 15-degree increments, not 45-degree increments. (I just tested it in Blender 2.83.3; it takes 6 key presses to rotate by 90 degrees.)

They are 15-degree increments indeed. My bad.

[rcorre]

Implemented 3D view "orbiting" shortcuts (that is apparently what blender calls them) in eb483de30656f1edeb1aa5efd0e5cca4a4c275c6.

[SecretPanda420]

Implemented 3D view "orbiting" shortcuts (that is apparently what blender calls them) in eb483de30656f1edeb1aa5efd0e5cca4a4c275c6.

Might as well add N9 for changing view 180 degrees. Other than that, looks perfect. I would add it myself but I'm not on my PC atm. :p

[ScribbleFen]

Cool to see someone else was working on something like this! I'll have to give it a try sometime; hope it gets added to the core soon ^^