Text Rotation + NURBS curves

Mar 30, 2009 at 9:25 PM
Edited Mar 30, 2009 at 9:26 PM
All in all, VERY nice work.  Looking forward to your next updates.

I see that the NURBS curves are disabled.  Is there a different/other/better way to put quadratic arcs in?  The Arc method works for symmetrical arcs, but not for asymetric arcs.  

Also, the netDxf.Entities.Text class's Rotation property does not seem to be working.

Great work, though!
Apr 7, 2009 at 2:48 AM

Thanks for the input and sorry for the delay. I have been busy and a little distracted.

I have checked the text rotation property and it seems to work as expected. Keep in mind that the rotation in expressed in degrees. Most of the angle properties in the dxf entities are in degrees, only a few that are in radians (for example start and end angle of an ellipse). So, to uniform that I have kept all angles in degrees, the writer will transform the values as needed.

The nurbs code is quite basic, and more that a work in progress is a learning in progress. I am still learning the math behind splines and how they are implemented in dxf files.

There are two ways to define splines in dxf files. One way is with polylines and the smooth type; the other way is with the Spline entity, both of them not implemented at the moment, sorry. The Spline entity is not compatible with dxf version 12, as far as I remember the first AutoCad version that implemented those was AutoCad 2000. By the way, the arc entity is just a circular arc defined by the center, the radius, the start and end angles.
AutoCad is far from being a good tool to work with curves much better is Rhinoceros. If you work mainly with nurbs you might want to check OpenNurbs www.opennurbs.org, it is open source, there is a net version, and it is the file format behind Rhinoceros.