3D draw layering

[jacobramirez-pt]

Encountering a strange issue with 3D coordinates and layering -- could not find a related issue on the GitHub.

You will notice that the "debug line" below appears on top of the cube's faces in the first call of the cube_block, which is expected as the line is drawn after the faces.
However, in the second call -- where the cube is just slightly larger, the line disappears behind the cuboid's filled faces?

Perhaps the strangest part is that the the 'inner' edges of the cuboid manage to stay on top of fills? I believe this might have to be because they are 'closest' to the viewing "camera" and thus not conflicting with the filled sides?

#import "@preview/cetz:0.4.0": *

#set page(width: auto, height: auto, margin: 0.6pt)

#let cube_block(
  pos: (0, 0, 0),
  dimensions: (1, 1, 1),
  ..style
) = {
  import draw: *

  set-origin((0, 0))

  let (x, y, z) = pos
  let (x_dim, y_dim, z_dim) = dimensions
  
  let vertices = ( // Cuboid vertices
    (x + x_dim, y, z),
    (x + x_dim, y + y_dim, z),
    (x, y + y_dim, z),
    (x, y + y_dim, z + z_dim),
    (x, y, z + z_dim),
    (x + x_dim, y, z + z_dim),
  )

  let outer_most_point = (x + x_dim, y + y_dim, z + z_dim)

  ortho({
    group({
      // Coloured faces
      line(vertices.at(0), vertices.at(1), outer_most_point, vertices.at(5), ..style, close: true, stroke: none)
      line(vertices.at(1), vertices.at(2), vertices.at(3), outer_most_point, ..style, close: true, stroke: none)
      line(vertices.at(3), vertices.at(4), vertices.at(5), outer_most_point, ..style, close: true, stroke: none)


      // DEBUG Line
      line((rel: (1, 0, 0.), to: vertices.at(2)), (rel: (0, 0, z_dim + 2)), ..style, stroke: 4pt)

     // Wireframe
      line(..vertices, ..style, close: true, fill: none)
      line(vertices.at(5), outer_most_point, ..style)
      line(vertices.at(1), outer_most_point, vertices.at(3), ..style, fill: none)
    })
  })
}

#canvas({
  import draw: *
  // Block of cubes -- arbitrary positions
  cube_block(pos: (-1, 0, 0), dimensions: (3, 3, 4), fill: red)
  cube_block(pos: (8, 4, 0), dimensions: (4, 3, 4), fill: red)})

For context I want to create a cuboid with lines together to give the effect of many cubes, however these inner 'grid' lines were being obscured in precisely the way seen above:

[johannes-wolf]

Encountering a strange issue with 3D coordinates and layering -- could not find a related issue on the GitHub.
...

You can pass sorted: false to ortho to disable its very naive element sorting.
I will create an issue about that.