yang686526

oddbdimension->measurement();
oddbdimension->measurement();
hi,
when iterating through model space with the attached drawing, i come accross some dimensions, and when i try and retreive there measurement value, dwgdirect return write error.
i assume i am doing something wrong, please let me know.
cheers
jason
example code i use is as follows :
int main(int argc, char* argv[])
{
:dinitialize(&dwgsvcs);
:drxinitwinntcrypt();
odrx_init_static_module_map();
{
oddbdatabaseptr dwgdb = dwgsvcs.readfile( "p:\\drawings\\foriegn_filenames\\inside files\\ax08-2.dwg", false, false, oda::ksharedenyno );
oddbblocktablerecordptr blocktableptr = dwgdb->getmodelspaceid().safeopenobject();
oddbobjectiteratorptr entityiteratorptr = blocktableptr->newiterator();
while( !entityiteratorptr->done() ) {
oddbentityptr entityptr = entityiteratorptr->entity(oddb::kforread);
oddbobjectid entityid = entityptr->objectid();
oddbhandle hentity = entityid.gethandle();
oddbobjectptr objectptr = entityid.openobject();
odgeextents3d extents;
try {
if ( entityptr->getgeomextents(extents) == eok ) {
// bad extents found
// ....
}
} catch (oderror& e) {
std::cout << "bad extents with oderror" << std::endl;
} catch ( ... ) {
std::cout << "bad extents" << std::endl;
}
odrxobjectptrarray primitives;
if ( entityptr->iskindof(oddbdimension::desc())) {
oddbdimensionptr dimptr = entityptr;
// throws exception here!
double dmeas = dimptr->measurement();
}
entityiteratorptr->step();
}
}
:drxuninitwinntcrypt();
:duninitialize();
return 0;
}
attached files
dimension entity stores a cached value for measurement. its negative value indicates that cache is invalid.
in dd 1.13 measurement() function tries to recalculate the value and update the dimension entity. if dimesion style is not set (null) it also sets style standard to dimension entity. if the entity was not opened for write exception is thrown.
in dd 1.14 measurement() which is const will always return cached value.
and getmeasurement() will try to recalculate the invalid cache. this function will be non-const and may require dimension entity be opened for write.
as a work around you can open dimension entity for write before calling measurement().
sergey slezkin
quote:
originally posted by sergey slezkin
dimension entity stores a cached value for measurement. its negative value indicates that cache is invalid.
in dd 1.13 measurement() function tries to recalculate the value and update the dimension entity. if dimesion style is not set (null) it also sets style standard to dimension entity. if the entity was not opened for write exception is thrown.
in dd 1.14 measurement() which is const will always return cached value.
and getmeasurement() will try to recalculate the invalid cache. this function will be non-const and may require dimension entity be opened for write.
as a work around you can open dimension entity for write before calling measurement().
what i did was call upgradeopen on the dimension, and then all was ok, the file did not get updated, which i hoped, will this always be the default behaviour (not updating the actual file) ?
also sergey, thanks for all your help to date, you have been very helpfull with many of my questions.
last edited by janderssen; 5th september 2005 at 06:05 pmfff">.
my understanding is that the dimension entity from your file gets updated:
1. negative measurement value stored in original file is changed to calculated value.
2. null dimstyle is changed to standard.
autocad does the same things loading such file.
(the file itself gets updated if you call writefile())
sergey slezkin