LVectorEllipticalArc::LockObject

#include "ltwrappr.h"

virtual L_INT LVectorEllipticalArc::LockObject(pObject)

pVECTORELLIPTICALARC pObject;

/* pointer to a vector object */

Gets the object information of the class object.

Parameter

Description

pObject

Pointer to a VECTORELLIPTICALARC structure to be updated with the vector object information.

Returns

SUCCESS

The function was successful.

< 1

An error occurred. Refer to Return Codes.

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.

Original object type

Possible object type following rotation

VECTOR_RECTANGLE

VECTOR_POLYGON

VECTOR_ELLIPSE

VECTOR_POLYDRAW

VECTOR_CIRCLE

VECTOR_POLYDRAW

VECTOR_ARC

VECTOR_POLYDRAW

VECTOR_ELLIPTICALARC

VECTOR_POLYDRAW

VECTOR_TEXT

VECTOR_POLYDRAW

VECTOR_PIE

VECTOR_POLYDRAW

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

LVKRN

For a listing of the exact DLLs and Libraries needed, based on the toolkit version, refer to Files To Be Included With Your Application.

See Also

Functions:

LVectorEllipticalArc::UnlockObject, Class Members

Topics:

Working with Vector Objects

Example

//Example112
// This example will add an elliptical arc object to the Active Layer LVectorBase object.

L_VOID Example112(HWND hWnd, LVectorBase *pVector)
{
   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);
   
   pVector->AddObject(&VectorEllipticalArc);
   
   //Now change color to blue
   MessageBox(NULL, TEXT("Changing color to red"), TEXT(""), MB_OK);
   
   VECTORELLIPTICALARC EllipticalArcTemp;
   
   VectorEllipticalArc.LockObject(&EllipticalArcTemp);

  EllipticalArcTemp.Pen.bExtPen = FALSE;
   EllipticalArcTemp.Pen.NewPen.LogPen.lopnColor = RGB(255,0,0);
   VectorEllipticalArc.UnlockObject(&EllipticalArcTemp);

   //LVectorEllipticalArc destructor called when VectorEllipticalArc goes out of scope
}