【转帖】a problem about spline
 

a problem about spline
a problem about spline
i have a problem about importing a spline. the attachment is the case file.
if importing this file into my application using opendwg, opendwg returns the degree of this spline is 1, but if importing it using dwgdirect 1.10 update 1, it returns the degree of the spline is 3. when using opendwg, my application works correctly with opendwg, but when using dwgdirect 1.10 update 1, it throws an exception.
thanks for your help!
attached files

quote:
originally posted by enigma
i have a problem about importing a spline. the attachment is the case file.
if importing this file into my application using opendwg, opendwg returns the degree of this spline is 1, but if importing it using dwgdirect 1.10 update 1, it returns the degree of the spline is 3. when using opendwg, my application works correctly with opendwg, but when using dwgdirect 1.10 update 1, it throws an exception.
which function do you use to obtain spline degree?
note that if function returns odresult other then eok, it is called incorrectly and no warranty it returns correct result.
for example, oddbspline::getfitdata always returns degree 3 since autocad always uses this degree for fit pointed splines. if spline is not fit pointed (like spline in your file), this function returns egeneralmodelingfailure result and should not be used.
sincerely yours,
george udov
a probleme about spline
i used both getfitdata and getnurbsdata to get the degree, but i called the getfitdata function after getnurbsdata, so the degree i got always was 3. we should use getnurbsdata to get the right degree of a spline if it is not fit pointed, it is right? thanks very much for your help.
quote:
originally posted by george udov
which function do you use to obtain spline degree?
note that if function returns odresult other then eok, it is called incorrectly and no warranty it returns correct result.
for example, oddbspline::getfitdata always returns degree 3 since autocad always uses this degree for fit pointed splines. if spline is not fit pointed (like spline in your file), this function returns egeneralmodelingfailure result and should not be used.

quote:
originally posted by enigma
we should use getnurbsdata to get the right degree of a spline if it is not fit pointed, it is right? thanks very much for your help.
yes, it is right.
btw, i think better way to obtain spline data is
code:
if(pspln->hasfitdata())
{
// spline is fit pointed
pspln->getfitdata(...);
}
else
{
// there are no fit data
pspln->getnurbsdata(...);
}
thank you for feedback.
sincerely yours,
george udov
a probleme about spline
quote:
originally posted by george udov
yes, it is right.
btw, i think better way to obtain spline data is
code:
if(pspln->hasfitdata())
{
// spline is fit pointed
pspln->getfitdata(...);
}
else
{
// there are no fit data
pspln->getnurbsdata(...);
}
thank you for feedback.
thanks for your advice. the function degree() of spline returns which degree, it's the value of getfitdata or getnurbsdata?
quote:
originally posted by enigma
thanks for your advice. the function degree() of spline returns which degree, it's the value of getfitdata or getnurbsdata?
it's the value of getnurbsdata ().
sincerely yours,
george udov