【转帖】spline Help
 

spline help
spline help
i'm a dwg newbie and i'm trying to figure out how to build a spline in my dwg file. i have a list of imported xyz data (this is actually lat, long, and height data in decimal format)
what i have done so far is init everything (as learned from the odwrite example) and then i populate my odgepoint3darray fitpoints array with odgepoint3d objects containing the xyz data. now according to the example i need to perform spline->setfitdata( ... ) in lies my question.
i have looked everywhere for a good definitions of the degree, start and end tangent, etc.. with no luck. what are each of these vars and are there any quick and easy ways to calculate them. i have tried a few different methods but during my file audit i always get the error "acdbspline(3d) control points of spline is coincident invalid removed". then when i open my dwg file in cad i get nothing, just a blank screen.
also, i have tested everything else and i can generate a spline with my code if i just use the block of code from the example where the fit points are hardcoded and simple values are used for degree, start, and end tangents
thanks in advance for any and all help
degree is always 3.
tolerance other than 0 is not supported in dwgdirect.
if you have no idea about start and end tangents you can specify zero length vectors (tangents are not defined)
be sure that fit points are not coincident.
sergey slezkin
thanks for your help!!
i have the bugs worked out of that portion and i have removed any repeat coordinates that were causing my error. now i have the problem that i can't see the spline inside of autocad. i can do a ctrl a to select all and then view the properties so i know the spline is there but it isn't visible.
again if i build the fitpoints using the 5ish hardcoded values from the example everything shows up fine so i'm very confident i'm init'ing everything correctly. i can send the file if needed, also i didn't know if my coordinates being in the 30's and 90's and the example values being between 0-15 had anything to do with it, but my assumption was that autocad had a "infinite" workspace unlike a photoshop image size or anything.
have you tried view/zoom extents in autocad?
if it does not help post the file please.
sergey slezkin
that did it i had only been trying zoom in and out till it said i was zoomed out (or in) all the way. i hadn't tried extents.
is there a way to set it in code so when the dwg file is opened it will center all drawn items (or at least make most of them viewable), or am i stuck always needing to perform a zoom->extents? autozoom flag maybe?
look into odwriteex sample. search for "zoom" in dbfiller.cpp
you'll find zooming of both ps and ms viewports.
sergey slezkin