Any way to display fixtures, clamps and other obstacles in the preview?

Hi,
I tried a bit of searching but with no luck. For now I'm kind of jogging around them and this way they are visible in the backplot. Is there any ready way to do this more half-permanent, like another layer which does not disappear? This could display mounting holes also, which would be very useful when using them to secure the part after initial machining, I could use that to put G54 in right place on the preview, with not much guessing.
If its not already possible, any pointers in the direction of solution are welcome.
Thanks!

this is manly a featurer of the CAM system
but you can use VISMACH to display your mashine

see the Example Mashine SIM Axis Vismach
and load your gcode there

there are people displaying thme in Gmoccapy or now on QTvcp

There are programming 'hooks' added in the master version of linuxcnc for user_plots.

it has not been exercised usefully that I know of. I had dabbled with some proof of concept with Qtvcp screens but got distracted by higher priority work.

Chris M