Spritestack – 3D pixelart editor based on sprite stacking technique
spritestack.io
spritestack.io
https://spritestack.io/editor/help/#introduction
It helps at least a little.
But unfortunately this is yet another site where the home page doesn't seem to give much context if you're not already part of whatever community it is. (What's sprite stacking? How is it different for a voxel editor? What need does this site meet that hasn't been met by other things?)
Not that you can't do 3D pixel art with them, but they certainly won't help you get there.
Edit: I just realized that maybe your question is broader than just pixel art. Open-source game development in general is a very underserved field; in terms of integrated game development environments, the best option I know of is Godot, and that's still miles behind a tool like Unity in terms of capabilities.
Audio production tools aren't great either, none of them integrate particularly well with the few game development tools that do exist. Good texture generators are difficult to come by; I believe Blender does have some functionality to this end, but it's not very accessible.
In terms of 3D modelling, Blender is decent, but suffers from bad UX (although that's being increasingly fixed, so that's great!).
I'm not aware of any production-ready general-purpose release/infrastructure tooling existing that's equivalent to something like Steam Workshop.
In short... there are basically almost no good, accessible open-source tools for game development, no matter what aspect of the process you look at.
There are plenty of voxel editors out there:
I'm not sure how "stacked sprites" differ from voxels, since this appears to be the same technique Westwood used in it's voxel engine; but voxels are the traditional "3d" pixel art.
I would suggest having the demo editor load a familiar shape, perhaps a house or a boat, to allow me to modify the object which is already in 3D space. That might help me understand the controls better (unsure).
Ah, HN. Why ye do not let me delete my account.
It appears to just be a stack of 1 pixel high sprites you draw one at a time, like a 3D printer might extrude.
...I mean, fair enough, but don’t invent a whole new word for a concept that already exists unless it’s actually different?
You raised my hopes, but of course we have different googles now.
With a bit of googling, you can find some of these engines - here's a start - Ken Silverman's VoxLap (if you don't know who he is - then I haz a sad):
http://advsys.net/ken/voxlap.htm
Note that these are not "small 3D cubes" - they are literally just pixels. It was a technique that was explored in the 1990s during the whole DOOM era, but machines weren't able to render fast enough, and 3D cards just kept getting better - and here we are today.
Again - you can find more than a few of these examples from the time, but the tech of the day just wasn't fast enough.
Editors for voxel objects didn't exist - but they didn't really need to, because regular 3D editors could create the objects.
Which makes me wonder how well those old engines would work today, if this "sprite stacking" thing works well. As I recall back then, the demos I recall seeing weren't terrible, they just weren't up to the performance levels needed for a game engine...
EDIT: Some more detail and history:
https://killscreen.com/articles/meet-the-voxel-pixel-cousin-...
However, not every engine supports 3d models / voxels, so sprite stacking is commonly used in combination with engines that only support 2d, by simply drawing each layer on top of the previous one but one pixel higher on the y axis.
Source: was an expert in rendering CT and MR data.
The scroll controls are very difficult to use on OSX with a track pad. It scrolls 3 or 4 levels at once. And I wish it had undo.