On Jul 20, 2013, at 1:43 PM, Talwinder saini wrote: > I was reading a "BRL-CAD documentation Volume IV – Converting Geometry > Between BRL-CAD and Other Formats" on page no 37,38,39 the conversion > commands of .g file in to .DXF, .IGES and .STL file are not give the > result as accurate it is in .g format. > For example [..snip..] > Is it an error in the converter it is expected output. If it is > expected output, how can I increase the number of faces?
Talwinder, Polygonal conversion rarely ever is as accurate as CAD representation in parametric form (e.g., as CSG+implicits, NURBS, or other spline surface forms). That's the point of CAD formats and why the industry doesn't use triangles (except for display). :) It's the expected output. You can increase the number of faces by specifying different tolerance values. The -a, -r, -n, and -D options all control the type, shape, and quantity of polygons that will result during export. Note that changing the defaults can be tricky. For a simple cylinder, it's easy, but for models with a variety of geometry, you have to read the docs to understand what each of those options do and experiment with the settings. You can very easily end up specify tolerances that generate too many polygons and you'll run out of memory or fill up your hard drive. General rule of thumb: start with big numbers and make them smaller. For your cylinder, try setting the -n (normal) tolerance to 5: g-stl -n 5 -o file.stl file.g object That ensures there's a polygon for every five degree difference, which will approximately increase the number of triangles about an order of magnitude (about 1500). Using a 1 degree angle will increase the count to somewhere around 200 times as many. You can play with different values, depending on your model. Cheers! Sean ------------------------------------------------------------------------------ See everything from the browser to the database with AppDynamics Get end-to-end visibility with application monitoring from AppDynamics Isolate bottlenecks and diagnose root cause in seconds. Start your free trial of AppDynamics Pro today! http://pubads.g.doubleclick.net/gampad/clk?id=48808831&iu=/4140/ostg.clktrk _______________________________________________ BRL-CAD Developer mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/brlcad-devel
