In my Rhino 5 (5.14.522.8390, 22/05/2017) I have defined a 3D curve that I want to export to DXF. The curve uses all three dimensions, these are the properties.
curve
ID: 8d9d3c32-75d1-4b4e-8b92-7162a6368d7a (25)
Layer name: 0
Render Material:
source = from layer
index = -1
Geometry:
Valid curve.
Open polyline with 305 points.
(165.731,-110.408,-26.2), (165.209,-119.887,-26.2), …, (150.185,-392.592,-8)
domain = 0 to 304
However, when I export to DXF Rhino will write a different curve in the DXF file:
the Z coordinates of all points are 171.5539778446933, and it seems like the Y in Rhino has become X in the DXF, and Z has become Y.
Very strange: the other curves in the same Rhino drawing export fine.
I have been playing around with this for some hours now without any progress - can someone please help me out ?
Perhaps you could make a copy of your file and delete everything except the culprit curve and another curve of similar complexity which seems to export OK and a few other kinds of objects. If it still displays the same problem, post it here for folks to experiment with?
Hi AIW, thanks for the suggestion.
I have uploaded four files (hope that this works) for my project “TwoCurvesForDXF”: the 3dm file, the DXF file that I get and two screenshots. The Rhino screenshot shows the design, the other screenshot shows the incorrect contents of the DXF (tested in several programs).
I have seen this happen in other apps. One of the curves is essentially a paper space object (no Z or Z=0). It is related to how the receiving application is interpreting the coordinates for the “2D” object.
Thanks for testing and for the suggestion about paper space. How can I see whether or not an object is a “paper space” object ? The properties of the curve do not mention such property. I construct in 3D and have not defined any “paper”. Or should I simply make sure that all curves in my 3D space have varying coordinates for X, Y and Z ?
I meant “paper” in a general way. I could have said plan, or perhaps working plane.
The terminology is not relevant. The problem exist because some assumption is made in the receiving software when the Z value is zero.
Here’s are screen cap from TurboCAD. Note how the coordinate display on the bottom changes. In one case the curve is recognized as a 2D object and no “Z” is displayed. In the other its a 3D object that has no Z dimension and is located at Z=0.
TurboCAD does keep the curves in the correct spatial relationship and at the moment I do not have an app that demonstrates the problem like you have shown.
I suspect if you simply move the curves together (so they are still in the same spatial relationship) some small distance in Z, the problem will disappear. Well, that is my theory anyway.
Cordoni: thanks for the suggestion. Indeed when I connect and join both curves the result is OK.
I need two seperate curves though, to create CNC toolpaths.
Pascal: your DXF indeed opens OK in Rhino, however not in any of the four CAM programs that I tried. There I get the result as shown in my first screenshot.
The very strange thing is that in the older Rhino build all works OK, so my assumption is that some bug has been introduced between both releases.
