【转帖】is oddbpolylinegetarcsegat90 working
 

is oddbpolyline::getarcsegat() working?
is oddbpolyline::getarcsegat() working?
the returned arc segment seems not to be too proper - my pline was:
line - 0,0 - 100,0
arc seg - 100,0 - 100,50
arc seg - 100,50 - 100,0
and getarcsegat() returns center point at 412,50 and -212,50 for the 2 arc segments.
is the wrong thing with me or with the function?
regards
chudomir
best regards
chudomir

sorry, i forgot to say that this method concenrs the odgecircarc3d version of the method...
best regards
chudomir

what about bulge values of arc segments? but in any case results look strange. does your pline have default normal direction (0,0,1)? note that 2d version of the function returns arc in ocs and 3d version - in wcs. i can try to look into the problem if you provide me with information enough to reproduce it.
sergey slezkin

hi sergey,
i need the center of the current arc segment - and i preferred the lazy thing instead of calculating it from the bulge
and i'm using the 3d version - i know the ecs and wcs - i need the center in wcs.
and the pline is in the xy plane - its normal vector is 0,0,1;
here is a piece of sample code - i check the points with the vc++ debugger
oddbpolylineptr ppline = oddbpolyline::cast(pobject);
for (unsigned int i=0; i<ppline->numverts()-1; i++) {
// check the bulge of the segment that comes
const double dbulge = ppline->getbulgeat(i);
// we have arc segment...
if (dbulge != 0.0 ) {
// gets the arc segments
odgecircarc3d arcseg;
ppline->getarcsegat(i,arcseg);
const odgepoint3d odptstartpt = arcseg.startpoint();
const odgepoint3d odptendpt = arcseg.endpoint();
const odgepoint3d odptcenter = arcseg.center();
const odgevector3d odvecnormal = arcseg.normal();
const odgevector3d odvecref = arcseg.refvec();
} //if
} //for
and here is the autocad commands with which i was drawing:
command: pline
specify start point: 100,0
specify next point or [arc/halfwidth/length/undo/width]: a
specify endpoint of arc or
[angle/center/direction/halfwidth/line/radius/second pt/undo/width]: 100,50
specify endpoint of arc or
[angle/center/close/direction/halfwidth/line/radius/second pt/undo/width]: 100,0
specify endpoint of arc or
[angle/center/close/direction/halfwidth/line/radius/second pt/undo/width]:
hope this helps?
regards
chudo
best regards
chudomir

hi chudomir,
surely getarcsegment is the right method to get arc center & radius instead of coding bulge computations yourself. the bug in this function is already fixed. i knew about it but asked for additional information because you wrote that you get arc centers at (412,50) & (-212, 50). the bug fixed could not produce such results. perhaps it was a misprint and you were getting (412,25) & (-212,25)?
sergey slezkin

thanks for the info, sergey.
may be it was a print error from myself.
have a nive work!
best regards
chudomir