DXF export oddities

When I export a 2d file into a dxf (r12 lines and arc) about half of the lines that were black in rhino come out white in the dxf if I reopen it in rhino, but not in bobcad. I have tried changing the color and putting everything on the same layer but it still comes out white again.

Not a huge problem but if I try to print sometimes, it will of course miss any white lines.


Can you post a sample file to test?

dxf export problem.dxf (401.1 KB)

here is a selection out of a nest for a cnc router

Hi James - I can repeat that - it rings a faint bell about how colors are handled, let me see what I can find out.

For now, if you make the color anything other than pure black, like very darkest gray, it should hold that color.



Thanks, that works.


If I start from scratch, with a new curve, it does hold the black color on round trip… so there is something I am missing still - yeah the white curves are set to color by object - if you set them to ‘by layer’ color it works as expected (black layer)


I’ll look through it in more detail, but Acad has a color index 7 that displays black on light backgrounds and white on dark backgrounds.

In your dxf file are some curves that are color by object - color index 18, which is always black, and some that are color by layer - layer 0 color 7, which is black on light background and light on dark background in Acad.

I see that Rhino writes color by object black and layer color black to color 7 black_or_white but isn’t consistent reading color 7 back into Rhino.
Rhino adjusts according to the background color reading layer colors and not when reading object colors.
I’ll fix that to be consistent.