【转帖】geometry issue
 

geometry issue
geometry issue
hi,
in objectarx we had several very useful functions: like this one:
inline double* asdblarray(const acgevector2d&);
we could use it in cases where array of 3 doubles were used. is this something like these in the dwg toolkit or can someone place them for the next release? of course we can use something like (&vec.x) for array but i'm not sure how afety it is.
regards
chudomir
best regards
chudomir

i'd prefer if you use your own definitions like
inline double * asdblarray(odgepoint2d & pt)
{return &pt.x;}
if we include them into common interface we need to be sure that it works correctly on all supported platforms.
sergey slezkin

ok, no problem. but the classes odgepoint2d/3d etc miss the #pragma pack(n) directive as in objectarx files. can this cause problems?
thanks.
chudomir delchev
best regards
chudomir

you are right that dwgdirect public headers must contain:
#pragma pack(push, ...)
....
#pragma pack(pop)
else client project can't have alignment different from one used while compiling dwgdirect.
but even without them problems with asdblarray can happen only if you use #pragma pack(16) in your project.
sergey slezkin

thanks for the info.
and here is a sample header for these, but i have no time to test them. anyway i thinke they should work:
[code]
#ifndef geassign_h
#define geassign_h
#pragma pack (push, 8)
class odgepoint2d;
class odgevector2d;
class odgepoint3d;
class odgevector3d;
inline odgepoint2d& aspnt2d(const double* pnt) {
return *((odgepoint2d*)pnt);
}
inline odgevector2d& asvec2d(const double* vec) {
return *((odgevector2d*)vec);
}
inline double* asdblarray(const odgepoint2d& pnt) {
return (double*)&pnt;
}
inline double* asdblarray(const odgevector2d& vec) {
return (double*)&vec;
}
inline odgepoint3d& aspnt3d(const double* pnt) {
return *((odgepoint3d*)pnt);
}
inline odgevector3d& asvec3d(const double* vec) {
return *((odgevector3d*)vec);
}
inline double* asdblarray(const odgepoint3d& pnt) {
return (double*)&pnt;
}
inline double* asdblarray(const odgevector3d& vec) {
return (double*)&vec;
}
#pragma pack (pop)
#endif
</pre><hr></blockquote>
best regards
chudomir

not sure that #pragma pack (push, 8) would compile on all dwgdirect-supported platforms...
sergey slezkin