Re: DXF bulge to I,J equations

Mike, Jeff,

May I suggest the TurboCNC list for controller innards discussions? I'm
sure Dave won't mind ;>)

Alan KM6VV


dumbdrive wrote:

>
> In what programing langauge? Basic? VB? Pascal? C, C++?
> I may have a sample depending on your langauge...
> The concept is a little difficult if you are not familiar with
> vectors and ArcTangents... The function ArcTangent(X,Y) gives
> different results depending upon the quadrant the X,Y value is
> found... Better read up on them, if you are not familiar with them
> already.
>
> If all that is too overwhelming, in some cad systems you
> can "explode" the polyline and it will turn it into arcs and line
> segments for you, then you won't have to worry about the bulges.
>
> Since you are decoding a dxf that contains polylines and vertex's,
> bear in mind that the closed polyline does not have the last vertex
> segment that points to the first vertex value starting value, you'll
> have to add that... so be sure to check if it is closed or open.
>
> I notice no responses so far to your request... I think there should
> be a group for programming question regarding motion control (cnc
> type) where ideas could be shared... I learn a lot from newsgroups,
> but most of the "programming" ones are database or something else
> specific.
>
> Mike
>
> --- In CAD_CAM_EDM_DRO@y..., "jeffskey1" <jeffskey1@a...> wrote:
> > Does anyone know the equation's to convert a DXF arc that is
> > expressed with a "bulge" value to I and J values as used with G-
> code
> > G02 or G03? I am writing a software program to convert and optimize
> a
> > PROTEL pcb dxf file to cnc G-code for my maxnc mill.
> >
> > Thanks
> > Jeff