If no 3D parameters are set, views and font size are used from the 2D settings. If the settings for 3D are set, then these overwrite the 2D settings (for 3D). The export of the 2D derivation remains unaffected.
Always visible: By default, dimensions are hidden if the respective view is rotated beyond a certain extent. If the option is activated, the respective dimensioning is always displayed regardless of the rotation status of the component. This can be advantageous for certain dimensions such as overall dimensions, for example.
The 2D view is also not affected.
This feature has been added with V12. In older versions the feature is simply ignored and so dimensioning displayed quite normal.
3D views [Views 3D]: You can define the views in which dimensions are displayed for 3D in contrast to 2D.
Font size 3D: You can define the font size in 3D differently from 2D.