QTPlasmaC with fourth axis - rotary

There are so many variables to keep track of. This has been an interesting experiment, I hope someone figures out how to get some decent look ahead for all axes in the not too distant future.

Now I can also see the jerky movement that I was expecting:
 

It's sure a lot faster than it was before

So I would think the question to ask then is it useable as is or not?

The problem seems to be that you would need insane acceleration values to reach feedrates of 20m/min with the one line look ahead. And of course the shorter the segments the higher the acceleration would need to be.
It's like driving on a road in fog, because you can't see what lies ahead you can only go so fast so you can react to changes. The thicker the fog the slower you go. Unless you could brake/speed up instantly, of course.
So, as I see it at least, this is beyond what LinuxCNC can do in its current state.

That is extremely sad news. I would never have thought that there is any place where Mach3 could out perform LinuxCNC. And the worst is I just built the base of my machine to take the fourth axis.
I really hope that someone clever will be looking at this issue in the very near future.

What was the cost of integrating the the trajectory planner that was suggested to be integrated but needed some cash to get it done? Can we not get the community to assist with this?

What was the cost of integrating the the trajectory planner that was suggested to be integrated but needed some cash to get it done? Can we not get the community to assist with this?

IIRC it was offered for free so it's not really a question of cash, it's a question of finding the right person with enough know how, time and motivation to do the work required to get it into the current LinuxCNC source.
I was only hinting that, IF cash helped, then I would happily donate some.