Hidden selection is invisible

[pierreporte]

Is there an existing issue for this?

• [X] I have searched the existing issues

Problem description

When something is selected in FreeCAD (solid, edge face, …) and the view is rotated so that the selection is hidden behind geometry, the selection is invisible. It is impossible to know that something has been selected. It is then hard for the user to identify exactly what has been selected for an operation, especially complex ones.

FreeCAD could always display the edges of the selection so that it stands out in the 3D view. To better indicate that the hidden part of the selection is behind existing objects, it could be dashed. The visible part of the selection would remain as it is today.

Full version info

OS: Ubuntu 23.10 (KDE/plasma)
Word size of FreeCAD: 64-bit
Version: 0.22.0dev.37249 (Git) AppImage
Build type: Release
Branch: main
Hash: 3acbc561f299b4cddea8215c387a52f3d5132cf6
Python 3.11.9, Qt 5.15.13, Coin 4.0.2, Vtk 9.2.6, OCC 7.7.2
Locale: French/France (fr_FR)
Installed mods: 
  * BillOfMaterials-WB 0.0.7
  * CosmeticThread3D
  * OpenTheme 2024.4.20
  * Curves 0.6.35
  * CurvedShapes 1.0.9
  * sheetmetal 0.4.13

Subproject(s) affected?

Core

Anything else?

Solidworks does it:

Code of Conduct

• [X] I agree to follow this project's Code of Conduct

[maxwxyz]

Related: https://github.com/FreeCAD/FreeCAD/issues/11214

[darrellenns]

Here's an example screen capture comparing behavior of linkstage to dev.

In linkstage, the transparency not only makes the current selection visible but also allows for easily selecting other obscured features. This significantly reduces the number of steps needed to make selections, and makes it much more intuitive.