原来一直纠结于状态的参数操作,位操作一只缠绕在心中,在看openmesh
Status.hh源代码时,发现enum和Status可以完成以下bool操作,一句话方便
#include <OpenMesh/Core/System/config.h>
//== NAMESPACES ===============================================================
namespace OpenMesh {
namespace Attributes {
//== CLASS DEFINITION ========================================================
/** Status bits used by the Status class.
* \see OpenMesh::Attributes::StatusInfo
*/
enum StatusBits {
DELETED = 1, ///< Item has been deleted
LOCKED = 2, ///< Item is locked.
SELECTED = 4, ///< Item is selected.
HIDDEN = 8, ///< Item is hidden.
FEATURE = 16, ///< Item is a feature or belongs to a feature.
TAGGED = 32, ///< Item is tagged.
TAGGED2 = 64, ///< Alternate bit for tagging an item.
FIXEDNONMANIFOLD = 128, ///< Item was non-two-manifold and had to be fixed
UNUSED = 256 ///< Unused
};
/** \class StatusInfo Status.hh <OpenMesh/Attributes/Status.hh>
*
* Add status information to a base class.
*
* \see StatusBits
*/
class StatusInfo
{
public:
typedef unsigned int value_type;
StatusInfo() : status_(0) {}
/// is deleted ?
bool deleted() const { return is_bit_set(DELETED); }
/// set deleted
void set_deleted(bool _b) { change_bit(DELETED, _b); }
/// is locked ?
bool locked() const { return is_bit_set(LOCKED); }
/// set locked
void set_locked(bool _b) { change_bit(LOCKED, _b); }
/// is selected ?
bool selected() const { return is_bit_set(SELECTED); }
/// set selected
void set_selected(bool _b) { change_bit(SELECTED, _b); }
/// is hidden ?
bool hidden() const { return is_bit_set(HIDDEN); }
/// set hidden
void set_hidden(bool _b) { change_bit(HIDDEN, _b); }
/// is feature ?
bool feature() const { return is_bit_set(FEATURE); }
/// set feature
void set_feature(bool _b) { change_bit(FEATURE, _b); }
/// is tagged ?
bool tagged() const { return is_bit_set(TAGGED); }
/// set tagged
void set_tagged(bool _b) { change_bit(TAGGED, _b); }
/// is tagged2 ? This is just one more tag info.
bool tagged2() const { return is_bit_set(TAGGED2); }
/// set tagged
void set_tagged2(bool _b) { change_bit(TAGGED2, _b); }
/// is fixed non-manifold ?
bool fixed_nonmanifold() const { return is_bit_set(FIXEDNONMANIFOLD); }
/// set fixed non-manifold
void set_fixed_nonmanifold(bool _b) { change_bit(FIXEDNONMANIFOLD, _b); }
/// return whole status
unsigned int bits() const { return status_; }
/// set whole status at once
void set_bits(unsigned int _bits) { status_ = _bits; }
/// is a certain bit set ?
bool is_bit_set(unsigned int _s) const { return (status_ & _s) > 0; }
/// set a certain bit
void set_bit(unsigned int _s) { status_ |= _s; }
/// unset a certain bit
void unset_bit(unsigned int _s) { status_ &= ~_s; }
/// set or unset a certain bit
void change_bit(unsigned int _s, bool _b) {
if (_b) status_ |= _s; else status_ &= ~_s; }
private:
value_type status_;
};
//=============================================================================
} // namespace Attributes
} // namespace OpenMesh
//=============================================================================
#endif // OPENMESH_ATTRIBUTE_STATUS_HH defined
//=============================================================================