2 Replies Latest reply on May 15, 2009 9:41 AM by gene.carman

    Setting "path closure" tolerance when building complex area fill shapes?

    gene.carman

      I seem to remember there was a command for defining how large the tolerace gap of endpoints of lines and arcs, in the shape edit mode, could be while allowing them to close to make a "path."

       

      This is old Board Station (EN2002 or En2004) using the shape edit mode to make complex shapes.  When using fillet and trim, there are gaps created that will not allow a "path" to be created if the gaps exceed a certain size.

       

      What is the command to modify that gap tolerance?

        • 1. Re: Setting "path closure" tolerance when building complex area fill shapes?
          foxdenman

          I do not recall that feature.  One of my former colleagues determined that the value for PI was off a little bit causing arcs and such to be off at times. I may be wrong but the lines you are filleting cannot be polygons or internal vertices on a path. Segments work the best .Please correct me if I am wrong.  As far as trimming, the only time I had issues were when an arc was not "right on" and would not actually cross, the line I was trimming to, at some point out there.

          • 2. Re: Setting "path closure" tolerance when building complex area fill shapes?
            gene.carman

            "I do not recall that feature.  One of my former colleagues determined that the value for PI was off a little bit causing arcs and such to be off at times. I may be wrong but the lines you are filleting cannot be polygons or internal vertices on a path. Segments work the best .Please correct me if I am wrong.  As far as trimming, the only time I had issues were when an arc was not "right on" and would not actually cross, the line I was trimming to, at some point out there."

             

            You are correct, you cannot trim or fillet a line (or segment) with a path or polygon.  

             

            The issue I was encountering was that using the fillet command should leave the arc endpoints at the same endpoint as the line segment(s) you did the fillet to; yet (and perhaps it is a PI error) there is often a gap, and that gap is too small to modify due to the graphic limitations of the tool (you cannot zoom in close enough to fix and grab the end points)  However, if that fillet created arc is converted to a path, and then to segments, it is only a series of lines, which can be grabbed and trimmed without having to zoom-in to the extreme.

             

            Once segment endpoints meet, (using the trim function) then all segments can be joined to create a path, which then can be converted to a polygon and eventually a fill.

             

            The error lies in the fact that arcs, arc fillets and circles do NOT end where they appear to end when using trim or fillet; there is often a small disjoint or "gap."   To workaround that disjoint, convert the resulting "almost perfect" arc to a path (specify your segment granularity) and then to segments, and you essentially are trimming lines with lines... which works fine.

             

            I had thought that there was a command that controlled the "gap snap" of endpoints when converting to paths...  apparently this is not the case.     So the workaround is converting arcs to segments to get rid of "gaps."  I had thought years ago that a command was created that allowed for a specific gap tolerance when converting to paths, thus this conversion to paths and segements would not have to be done to create a complete closed path.  But again, apparently this is not the case.  So conversion and trimming is required to get a complete path.

             

            BTW the same gaps also appear when using the copy > offset command on a known good closed path to create a larger or smaller size closed path.  Again convert to segments and find the gap (or overlap) and trim, then convert back to path and polygon and eventually fill.

             

            One only need do this if creating complex shapes involving arcs and circle segments.  Simple shapes made with line segments only do not seem to have these "gap" issues.