我正在编译一个使用 Autodesk Maya API 的程序，并收到有关构造函数在此上下文中为私有(private)的错误:
/usr/autodesk/maya2013-x64/include/maya/MFnTransform.h: In member function ‘MayaEggGroup* MayaEggLoader::MakeGroup(EggGroup*, EggGroup*)’:
/usr/autodesk/maya2013-x64/include/maya/MFnTransform.h:181:2: error: ‘MFnTransform::MFnTransform(const MFnTransform&)’ is private
pandatool/src/mayaegg/mayaEggLoader.cxx:373:60: error: within this context
一点背景 - 我正在构建 Panda3D ，(开源游戏引擎)，在 Ubuntu 12.04 上，使用 Maya 2013。它在编译将文件从 Maya 转换为 Panda 模型格式的导出器的构建部分中令人窒息。
我(有点)理解错误的含义，但不知道如何解决它。奇怪的是，相同的代码可以在 Maya 2011 和 Maya 2012 中正常编译，并且据我所知，Maya 2013 中的类声明 (MFnTransform) 没有更改。
这是完整的 g++ 命令:
g++ -ftemplate-depth-30 -fPIC -c -o built/tmp/mayaegg2013_loader.o -Ibuilt/tmp -Ibuilt/include -I/usr/include/python2.7 -I/usr/include/eigen3 -I/usr/autodesk/maya2013-x64/include -DMAYAVERSION=MAYA2013 -DMAKEPANDA= -Ipandatool/src/mayaegg -Ipandatool/src/maya -pthread -msse2 -ggdb -D_DEBUG pandatool/src/mayaegg/mayaEggLoader.cxx
以及一些相关的代码。
在 mayaEggLoader.cxx 中，错误源自此处:
class MayaEggGroup
{
public:
string _name;
MObject _parent;
MObject _group;
bool _addedEggFlag;
};
MayaEggGroup *MayaEggLoader::MakeGroup(EggGroup *group, EggGroup *context)
{
MStatus status;
MayaEggGroup *result = new MayaEggGroup;
...
MFnTransform tFn = MFnTransform(result->_group, &status);
在 MFnTransform.h 中，这是 MFnTransform 定义的开头:
class OPENMAYA_EXPORT MFnTransform : public MFnDagNode
{
declareDagMFn( MFnTransform, MFn::kTransform );
public:
MObject create( MObject parent = MObject::kNullObj,MStatus * ReturnStatus = NULL );
...
我根本看不到私有(private)构造函数是在哪里定义的......我该如何寻找它？或者这个错误是否意味着其他事情实际上是错误的？
更新:
事实证明，这是 Maya 2013 C++ API 中引入的已知错误:
MAYA-6512: MFnDependencyNode, MFnDagNode copy constructor should be public, not private Workaround: Create a new functionset which operates on the same object, for example: MFnDependencyNode fn2(fn1.object()); If you want to pass a functionset to another method, pass a reference instead.
好的，但是如果我需要设置一个成员变量怎么办？这是我遇到同样错误的另一个地方。
MayaBlendDesc::
MayaBlendDesc(MFnBlendShapeDeformer deformer, int weight_index)
{
_weight_index=weight_index;
_deformer=deformer;
ostringstream strm;
strm << _deformer.name().asChar() << "." << _weight_index;
set_name(strm.str());
_anim = (EggSAnimData *)NULL;
}
在“_deformer=deformer”行上。
以下是 MayaBlendDesc 的定义。这是我可以编辑的代码。
////////////////////////////////////////////////////////////////////
// Class : MayaBlendDesc
// Description : A handle to a Maya blend shape description. This is
// just one target of a Maya BlendShape object, and
// thus corresponds more or less one-to-one with a
// single Egg morph target. (We don't attempt to
// support Maya's chained target shapes here; should we
// need to later, it would mean breaking each of those
// target shapes on the one continuous Maya slider into
// a separate MayaBlendDesc object, and synthesizing the
// egg slider values appropriately.)
////////////////////////////////////////////////////////////////////
class MayaBlendDesc : public ReferenceCount, public Namable {
public:
MayaBlendDesc(MFnBlendShapeDeformer deformer, int weight_index);
~MayaBlendDesc();
void set_slider(PN_stdfloat value);
PN_stdfloat get_slider() const;
private:
void clear_egg();
MFnBlendShapeDeformer _deformer;
int _weight_index;
EggSAnimData *_anim;
public:
static TypeHandle get_class_type() {
return _type_handle;
}
static void init_type() {
ReferenceCount::init_type();
Namable::init_type();
register_type(_type_handle, "MayaBlendDesc",
ReferenceCount::get_class_type(),
Namable::get_class_type());
}
private:
static TypeHandle _type_handle;
friend class MayaNodeTree;
};
这是 MFnBlendShape 及其祖先的定义(Maya API 的一部分，我无法触及):
class OPENMAYAANIM_EXPORT MFnBlendShapeDeformer : public MFnDependencyNode
{
declareMFn(MFnBlendShapeDeformer, MFnDependencyNode );
public:
//! Specifies the space to use for the deformation origin.
enum Origin {
kLocalOrigin, //!< \nop
kWorldOrigin //!< \nop
};
//! Specifies where in the shape's history to place the deformer.
enum HistoryLocation {
kFrontOfChain, //!< \nop
kNormal //!< \nop
};
MObject create( MObject baseObject,
Origin originSpace = kLocalOrigin,
MStatus * ReturnStatus = NULL );
MObject create( const MObjectArray& baseObjects,
Origin originSpace = kLocalOrigin,
HistoryLocation = kNormal,
MStatus * ReturnStatus = NULL );
MStatus addBaseObject( MObject & object );
MStatus getBaseObjects( MObjectArray & objects ) const;
MStatus addTarget( const MObject & baseObject, int weightIndex,
const MObject & newTarget, double fullWeight );
MStatus removeTarget( const MObject & baseObject,
int weightIndex,
const MObject & target,
double fullWeight );
MStatus getTargets( MObject baseObject, int weightIndex,
MObjectArray & targetObjects ) const;
unsigned int numWeights( MStatus * ReturnStatus = NULL ) const;
MStatus weightIndexList( MIntArray& indexList ) const;
MStatus targetItemIndexList( unsigned int weightIndex,
MObject baseObject,
MIntArray& targetItemIndices ) const;
float weight( unsigned int index, MStatus * ReturnStatus = NULL ) const;
MStatus setWeight( unsigned int index, float weight );
float envelope( MStatus * ReturnStatus = NULL ) const;
MStatus setEnvelope( float envelope );
Origin origin( MStatus * ReturnStatus = NULL ) const;
MStatus setOrigin( Origin space );
BEGIN_NO_SCRIPT_SUPPORT:
declareMFnConstConstructor( MFnBlendShapeDeformer, MFnDependencyNode );
END_NO_SCRIPT_SUPPORT:
protected:
// No protected members
private:
// No private members
};
MFnDependencyNode:
// ****************************************************************************
// CLASS DECLARATION (MFnDependencyNode)
//! \ingroup OpenMaya MFn
//! \brief Dependency node function set.
/*!
MFnDependencyNode allows the creation and manipulation of dependency
graph nodes. Traversal of the dependency graph is possible using
the getConnections method.
This function set does not support creation or removal of connections.
MDGModifier should be used for that purpose.
*/
class OPENMAYA_EXPORT MFnDependencyNode : public MFnBase
{
declareMFn(MFnDependencyNode, MFnBase);
public:
//! Specifies the scope of the attribute.
enum MAttrClass {
kLocalDynamicAttr = 1, //!< Dynamically added, applies to this specific node.
kNormalAttr, //!< Static attribute which is part of the original definition for this node type.
kExtensionAttr, //!< Extension attribute which is part of all nodes of this or derived node types
kInvalidAttr //!< None of the above
};
MObject create( const MTypeId &typeId,
MStatus* ReturnStatus = NULL );
MObject create( const MTypeId &typeId,
const MString& name,
MStatus* ReturnStatus = NULL );
MObject create( const MString &type,
MStatus* ReturnStatus = NULL );
MObject create( const MString &type,
const MString& name,
MStatus* ReturnStatus = NULL );
MTypeId typeId( MStatus* ReturnStatus = NULL ) const;
MString typeName( MStatus* ReturnStatus = NULL ) const;
MString name( MStatus * ReturnStatus = NULL ) const;
MString pluginName( MStatus * ReturnStatus = NULL ) const;
MString setName( const MString &name,
bool createNamespace = false,
MStatus * ReturnStatus = NULL );
MStatus getConnections( MPlugArray& array ) const;
unsigned int attributeCount( MStatus* ReturnStatus=NULL) const;
MObject attribute( unsigned int index,
MStatus* ReturnStatus=NULL) const;
MObject reorderedAttribute( unsigned int index,
MStatus* ReturnStatus=NULL) const;
MObject attribute( const MString& attrName,
MStatus* ReturnStatus=NULL) const;
MAttrClass attributeClass( const MObject& attr,
MStatus* ReturnStatus=NULL) const;
MStatus getAffectedAttributes ( const MObject& attr,
MObjectArray& affectedAttributes ) const;
MStatus getAffectedByAttributes ( const MObject& attr,
MObjectArray& affectedByAttributes ) const;
MPlug findPlug( const MObject & attr, bool wantNetworkedPlug,
MStatus* ReturnStatus=NULL) const;
MPlug findPlug( const MString & attrName, bool wantNetworkedPlug,
MStatus* ReturnStatus=NULL) const;
// Obsolete
MPlug findPlug( const MObject & attr,
MStatus* ReturnStatus=NULL) const;
// Obsolete
MPlug findPlug( const MString & attrName,
MStatus* ReturnStatus=NULL) const;
MStatus addAttribute ( const MObject & attr );
MStatus removeAttribute ( const MObject & attr );
MPxNode * userNode( MStatus* ReturnStatus=NULL ) const;
bool isFromReferencedFile(MStatus* ReturnStatus=NULL) const;
bool isShared(MStatus* ReturnStatus=NULL) const;
bool hasUniqueName(MStatus* ReturnStatus=NULL) const;
MString parentNamespace(MStatus* ReturnStatus=NULL) const;
bool isLocked(MStatus* ReturnStatus=NULL) const;
MStatus setLocked( bool locked );
static MString classification( const MString & nodeTypeName );
bool isNewAttribute( const MObject& attr,
MStatus* ReturnStatus=NULL) const;
static unsigned int allocateFlag(
const MString pluginName, MStatus* ReturnStatus=NULL
);
static MStatus deallocateFlag(const MString pluginName, unsigned int flag);
static MStatus deallocateAllFlags(const MString pluginName);
MStatus setFlag(unsigned int flag, bool state);
bool isFlagSet(unsigned int flag, MStatus* ReturnStatus=NULL) const;
bool isDefaultNode(MStatus* ReturnStatus=NULL) const;
MStatus setDoNotWrite ( bool flag );
bool canBeWritten(MStatus* ReturnStatus=NULL) const;
bool hasAttribute(const MString& name, MStatus* ReturnStatus=NULL) const;
MObject getAliasAttr(bool force, MStatus* ReturnStatus=NULL);
bool setAlias(const MString& alias,const MString& name, const MPlug& plug, bool add=true,
MStatus* ReturnStatus=NULL);
bool findAlias(const MString& alias, MObject& attrObj, MStatus* ReturnStatus=NULL) const;
bool getAliasList(MStringArray& strArray, MStatus* ReturnStatus=NULL);
MString plugsAlias(const MPlug& plug, MStatus* ReturnStatus=NULL);
MStatus setIcon( const MString &filename );
MString icon( MStatus* ReturnStatus=NULL ) const;
BEGIN_NO_SCRIPT_SUPPORT:
//! OBSOLETE FUNCTION, NO SCRIPT SUPPORT
MString setName( const MString &name,
MStatus * ReturnStatus );
//! NO SCRIPT SUPPORT
declareMFnConstConstructor( MFnDependencyNode, MFnBase );
//! NO SCRIPT SUPPORT
bool getPlugsAlias(const MPlug& plug, MString& aliasName, MStatus* ReturnStatus=NULL);
END_NO_SCRIPT_SUPPORT:
// turn on timing on for all nodes in the DG
static void enableDGTiming(bool enable);
// For turning node timing on and off, and querying the state...
MStatus dgTimerOn();
MStatus dgTimerOff();
//! Possible states for the node's timer.
enum MdgTimerState {
kTimerOff, //!< \nop
kTimerOn, //!< \nop
kTimerUninitialized, //!< \nop
kTimerInvalidState //!< \nop
};
MdgTimerState dgTimerQueryState( MStatus* ReturnStatus = NULL );
// For resetting node timers to zero...
MStatus dgTimerReset();
//! The different timer metrics which can be queried.
enum MdgTimerMetric {
// Primary metrics. The qualities that we measure.
kTimerMetric_callback, //!< Time spent within node callbacks for this node.
kTimerMetric_compute, //!< Time spent within the compute method for this node.
kTimerMetric_dirty, //!< Time spent propogating dirty messages from this node.
kTimerMetric_draw, //!< Time spent drawing this node.
kTimerMetric_fetch, //!< Time spent fetching data from plugs.
// Sub metrics. These are finer-grained breakdowns of the primary
// metrics. There could be many combinations of the above metrics.
// Currently we only support the following.
kTimerMetric_callbackViaAPI, //!< Time spent in callbacks which were registered through the API.
kTimerMetric_callbackNotViaAPI, //!< Time spent in callbacks not registered through the API (i.e internal Maya callbacks).
kTimerMetric_computeDuringCallback, //!< Time spent in this node's compute while executing node callbacks on any node.
kTimerMetric_computeNotDuringCallback //!< Time spent in this nodes compute when not executing any node callbacks on any nodes.
};
//! The types of timers which can be queried.
enum MdgTimerType {
/*!
Time spent performing an operation, not including any time
spent by child operations. For example, if we are drawing a
node and that requires a compute, self time will only include
the time spent drawing and not the compute time. Self time
measures wall-clock time as opposed to CPU time and the values
are in seconds.
*/
kTimerType_self,
/*!
Time spent performing an operation including all time spent by
child operations. For example, if we are drawing a node and
that requires a compute, inclusive time is the time for the
draw plus compute. Inclusive time measure wall-clock time as
opposed to CPU time and the values are in seconds.
*/
kTimerType_inclusive,
/*!
The number of operations that occurred. Ideally we should
return an integer when this timer type is queried, but there
are two advantages to using a double. 1) it keeps the interface
consistent and 2) integer has a fixed upper bound of roughly
four billion so using a double allows us to exceed this.
*/
kTimerType_count
};
// Query the timer value given a given metric and timer type.
double dgTimer( const MdgTimerMetric timerMetric,
const MdgTimerType timerType,
MStatus* ReturnStatus = NULL ) const;
// Query the callback timer values.
MStatus dgCallbacks( const MdgTimerType type,
MStringArray &callbackName,
MDoubleArray &value );
// Query the callbackId timer values.
MStatus dgCallbackIds( const MdgTimerType type,
const MString &callbackName,
MCallbackIdArray &callbackId,
MDoubleArray &value );
// Obsolete
MStatus addAttribute ( const MObject & attr, MAttrClass type );
// Obsolete
MStatus removeAttribute ( const MObject & attr, MAttrClass type );
protected:
// No protected members
private:
// No private members
};
和 MFnBase:
// ****************************************************************************
// CLASS DECLARATION (MFnBase)
//! \ingroup OpenMaya MFn
//! \brief Function Set Base Class.
/*!
Defines the interface for the API RTTI and Maya Object attachment
methods common to all Function Set Classes.
Implements the Function Set compatibility test methods for all
Function Sets.
The API provides access to Maya Objects as generic MObjects. Under
the C++ class scheme MObjects simply have type MObject with no base
or derived hierarchy. However, MObjects may be many different types
of model or scene objects, from Attributes to Transforms, within
Maya. This allows many different types of objects to be moved
across or accessed through the API without undue concern on the part
of plug-in developers for the type of object being manipulated.
Since it is impractical to provide every applicable method on
MObjects, the methods applicable to Maya Objects are encapsulated in
Function Sets. Function Sets can be attached to compatible MObjects
to provide an external interface to methods appropriate to that
MObject. All Function Sets provide a method setObject() which
attaches them to the specified Maya Object. Additionally, most
Function Sets provide a version of their constructor which attaches
the new Function Set to a specified MObject.
The link between an MObject and the role it performs as a Maya scene
or model object, as well as the compatibility between MObjects and
Function Sets is managed by the API Run-Time Type Identification
(RTTI) system. The two key concepts of this system are the Maya
Object type and the Function Set type (both are MFn::Type). All
MObjects have one and only one Maya Object type. All Function Sets
have one and only one Function Set type. MObjects may, however, be
compatible with many types of Function Sets. This compatibility
follows the class hierarchy of the Function Sets. Thus an MObject
with Maya Object type MFn::kNurbsSurface would be compatible with
MFnNurbsSurface, MFnDagNode, MFnDependencyNode, MFnNamedObject and
MFnBase.
Any MObject can be queried with the MObject::hasFn() method to
determine if it is comaptible with a given Function Set.
The purpose of the Base Function Set (MFnBase) is to provide methods for
determining whether or not a Function Set is compatible with a given Maya
Object (MObject) type (MFn::Type) or a specific MObject. See:
MFnBase::hasObj(MFn::Type)
and
MFnBase::hasObj(const MObject &)
As well, this Function Set provides virtual methods for determining the type
of a Function Set under the API RTTI system.
*/
class OPENMAYA_EXPORT MFnBase
{
public:
virtual ~MFnBase();
virtual MFn::Type type() const;
bool hasObj( MFn::Type ) const;
bool hasObj( const MObject & ) const;
MObject object( MStatus* ReturnStatus = NULL ) const;
virtual MStatus setObject( MObject & object );
BEGIN_NO_SCRIPT_SUPPORT:
//! NO SCRIPT SUPPORT
virtual MStatus setObject( const MObject & object );
END_NO_SCRIPT_SUPPORT:
static const char* className();
protected:
MFnBase();
void setPtr( MPtrBase* );
void setPtr( const MPtrBase* );
void setPtrNull();
virtual bool objectChanged( MFn::Type, MStatus * );
MPtrBase* f_ptr; // initialized/set with volatile
const MPtrBase* f_constptr; // initialized/set with volatile/const
// Specific for function sets which use internally reference
// counted objects! Only those function sets which use these
// objects need to set this to true. By default it is set to
// false.
//
// Classes which do not use internally reference counted objects
// must not tamper with this boolean value. Doing so can cause
// crashes when dealing with manually deleted objects.
//
bool fIsReferenceCounted;
private:
MFnBase( const MFnBase &rhs );
MFnBase & operator=( const MFnBase & );
MFnBase * operator& () const;
};
// ****************************************************************************
#define declareMinimalMFn( MFnClass ) \
public: \
virtual MFn::Type type() const; \
virtual ~MFnClass(); \
\
static const char* className(); \
\
private: \
MFnClass( const MFnClass &rhs ); \
MFnClass & operator=( const MFnClass & ); \
MFnClass * operator& () const;
#define declareMFn( MFnClass, MFnParentClass ) \
declareMinimalMFn( MFnClass ); \
public: \
MFnClass() {}; \
MFnClass( MObject & object, MStatus * ReturnStatus = NULL )
#define declareMFnConstConstructor( MFnClass, MFnParentClass ) \
MFnClass( const MObject & object, MStatus * ReturnStatus = NULL )
// Standard MFn class interface *without* the class constructor. This
// is to allow derived MFn classes to optionally specify their own
// custom constructor. For example if they wanted to declare that they
// use internally reference counted objects, they could set fIsReferenceCounted
// to true inside their own custom constructor.
//
#define declareMFnNoVoidConstructor( MFnClass, MFnParentClass ) \
declareMinimalMFn( MFnClass ); \
public: \
MFnClass( MObject & object, MStatus * ReturnStatus = NULL )
#define declareMFnNoVoidConstructorConstConstructor( MFnClass, MFnParentClass ) \
MFnClass( const MObject & object, MStatus * ReturnStatus = NULL )
#endif /* __cplusplus */
#endif /* _MFnBase */
最佳答案
我没有看到 MFnTransform::MFnTransform(const MFnTransform&)构造函数在任何地方定义(您没有提供足够的代码，但我假设它已被隐式定义为私有(private))，但这没关系 - 您可能不需要它。只需更改:
MFnTransform tFn = MFnTransform(result->_group, &status);
至:
MFnTransform tFn(result->_group, &status);
关于C++ 和 Maya : constructor is private within this context，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/12067653/