some lines are misplaced

[stef_d]

When i load up a dxf file exported from sketchup, i often end up with some of the lines mislplaced (they seemed to be mirrored on the y axis).
not all the lines suffer from this, and not all the time. i tried various options (R12, R13, or R14) without improvement.
The dxf load correctly in autocad, but dont in CAMBAM.
also, resaving from autocad does not help.
my guess is something messing up at the loading stage in CAMBAM ?
anyone seen this before ?

[Tweakie]

I think CamBam is still defined as 'under development' and there are quite a few little quirks remaining.
You could try asking Danny at http://www.cnc4free.org/phpBB3/viewforum.php?f=9 as he is pretty clever with Cam Bam.

Tweakie.

[10bulls]

Hi there!
Is it possible to upload a sample DXF file to take a look at? Also, can you tell me what version of CamBam you are trying?
That would be a big help and I will investigate straight away.

I know a lot of people have been successfully using CamBam with Sketchup and the DXF importing has been pretty well tested.

There is also a direct Sketchup to CamBam plugin here:
http://www.cerebralmeltdown.com/cncs...rt/default.htm

[stef_d]

Originally Posted by 10bulls Hi there! Is it possible to upload a sample DXF file to take a look at? Also, can you tell me what version of CamBam you are trying? That would be a big help and I will investigate straight away. I know a lot of people have been successfully using CamBam with Sketchup and the DXF importing has been pretty well tested. There is also a direct Sketchup to CamBam plugin here: http://www.cerebralmeltdown.com/cncs...rt/default.htm

sure, i'll do this tonight.
along with a few screen shots.
I am using the free version.

[stef_d]

here is one of the "faulty" dxf.
it's a continuous curve, set on a few layers, to avoid crossing on the same layer. when opened in sketchup, and autocad, it's fine. when loaded in CamBam, some sections of the curve are on the wrong side of the x axis.
somehow, applying the -1 transform on the x axis solves the problem... but it comes back when trying to join the fixed polylines with healthy ones..

[10bulls]

Thank you very much for that.

Looks like DXF still has some surprises for me!

The problem is due to some extra optional attributes Sketchup has put on some of the shapes, called the Extrusion direction. Why? and why on only some drawing objects? Who knows.

Typical of Autodesk's DXF documentation, they are pretty tight lipped on what extrusion should actually mean for each object type. From what information I can gather, for line segments it should be the direction of the thickness of a line, but I haven't yet come accross any details for arcs (or other shapes).

Apparently from how Autocad behaves, an arc 'extrusion' of 0,0,-1 means - "mirror this about the Y axis". Of course!

Thank you very much for pointing this one out! I will put in a change in the next release to look out for these settings and transform the shapes accordingly.

[10bulls]

I forgot to mention a work-around for the time being until I can put a fix in place.

First of all, select all the shapes and convert them to polylines (CTRL+A, CTRL+P).

Then select and rotate the objects on the wrong side of the axis by 180 degrees around the Y axis.

Then Do Edit-Apply Transformations.

Join should then work OK.

[stef_d]

Thanks for looking into this so quickly.
I will try the quick fix and let you know.

Very neat piece of software in all other aspects though.