Line tool refuses to work in perspective view until I undo Import of model

is there a limit reached and how can I tell ?

I imported a model from Photomodeler (photogrammetry prog creates rhino output) then was unable to use leader or draw a line in perspective view.
The model is one that already exists in the project, three times in fact at different scales,
line tool works with the three but importing this again with some extra lines and points added to it in Photomodeler sees line tool refuse to draw in perspective view yet work in orthos.
Edit undo the import and now line tool etc works in prerspective view.

have I reached some kind of limit ? How does one check ?

I am by the way on 24Gb ram having had an 8Gb stick fail, so using a pair of Corsair Vengeance Pro Red DDR3 8Gb and a single stick from the second pair, duffer due to go in post.

Turning off layers for all existing items and all but one of the imported Photomodeler models sees line tool now work, but with 4Gb GTX970 it cant be a video thing, can it ?


How much memory is in use?

Bottom of Rhino screen the amount of memory used by Rhino is shown.

Task Manager in Windows shows total memory use.

And I assume you are using a 64 bit version of Rhino …

Try opening the Rhino file from PhotoModeler directly in Rhino, not with anything else. Does everything work okay?

One option which is probably not the cause, under your display options for what your view is (Shaded, wireframe, etc…) If Isoline display is turned off, it will not show curves / lines. I ran into this once before. I use shaded with out isocurves for some of the projects I work on and it won’t show any curves or lines you have in your model space.