LVectorEllipticalArc::LockObject

#include "ltwrappr.h"

virtual L_INT LVectorEllipticalArc::LockObject(pEllipticalArc)

Gets the object information of the class object.

Returns

Comments

This function is used to retrieve the object information of the class object.

To use this method, declare a variable of the VECTORELLIPTICALARC type and pass the address to this function. After modifying the vector object settings, call LVectorEllipticalArc::UnlockObject (). LVectorEllipticalArc::LockObject () and LVectorEllipticalArc::UnlockObject () should always be called in pairs.

Before an object has been added to the LVectorBase object, using LVectorBase::AddObject or LVectorLayer::AddObject, LVectorEllipticalArc::UnlockObject () can be used to change ALL properties of an object. However, once the object has been added to the LVectorBase object, some properties cannot be changed using LVectorEllipticalArc::UnlockObject ().However, as long as the number of points does not change, the coordinates of the individual points can always be modified using LVectorEllipticalArc::UnlockObject ().

To change the object information for a class object, call LVectorEllipticalArc::UnlockObject.

LVectorEllipticalArc::LockObject and LVectorEllipticalArc::UnlockObject must be called in pairs.

Note that rotating an object may change the object type. However, not all object types are changed by rotation, and not all rotations result in changing an object type. For example, a rectangle rotated 90 degrees about the z-axis is still a rectangle. A rectangle rotated 45 degrees about the z-axis becomes a polydraw object. The table below indicates object types that may change following rotation and the possible resulting object types.

If an object type changes, LVectorEllipticalArc::LockObject and LVectorEllipticalArc::UnlockObject will return WRPERR_VECTOR_INVALID_OBJECT_TYPE. Object properties can still be inspected and changed by using LVectorObject::GetObjectAttributes and LVectorObject::SetObjectAttributes.

Required DLLs and Libraries

L_INT LVectorEllipticalArc__LockObjectExample(HWND hWnd, LVectorBase *pVector) 
{ 
   UNREFERENCED_PARAMETER(hWnd); 
   L_INT                nRet; 
   VECTORELLIPTICALARC  EllipticalArc; 
   //Create Elliptical Arc Object 
   EllipticalArc.Point.x = 50; 
   EllipticalArc.Point.y = 50; 
   EllipticalArc.Point.z = 0; 
   EllipticalArc.xRadius = 10; 
   EllipticalArc.yRadius = 20; 
   EllipticalArc.StartAngle = 45; 
   EllipticalArc.SweepAngle = 90; 
   EllipticalArc.Pen.bExtPen = FALSE; 
   EllipticalArc.Pen.nSize = sizeof( VECTORPEN ); 
   EllipticalArc.Pen.NewPen.LogPen.lopnStyle = PS_SOLID; 
   EllipticalArc.Pen.NewPen.LogPen.lopnWidth.x = 10; 
   EllipticalArc.Pen.NewPen.LogPen.lopnWidth.y = 10; 
   EllipticalArc.Pen.NewPen.LogPen.lopnColor = RGB(0,255,0); 
   LVectorEllipticalArc VectorEllipticalArc(&EllipticalArc); 
   nRet = pVector->AddObject(&VectorEllipticalArc); 
   if(nRet != SUCCESS) 
      return nRet; 
   //Now change color to blue 
   MessageBox(NULL, TEXT("Changing color to red"), TEXT(""), MB_OK); 
   VECTORELLIPTICALARC EllipticalArcTemp; 
   nRet = VectorEllipticalArc.LockObject(&EllipticalArcTemp); 
   if(nRet != SUCCESS) 
      return nRet; 
   EllipticalArcTemp.Pen.bExtPen = FALSE; 
   EllipticalArcTemp.Pen.NewPen.LogPen.lopnColor = RGB(255,0,0); 
   nRet = VectorEllipticalArc.UnlockObject(&EllipticalArcTemp); 
   if(nRet != SUCCESS) 
      return nRet; 
   //LVectorEllipticalArc destructor called when VectorEllipticalArc goes out of scope 
   return SUCCESS; 
}