LVectorSpline::LockObject

#include "ltwrappr.h"

virtual L_INT LVectorSpline::LockObject(pObject)

pVECTORSPLINE pObject;

/* pointer to a vector object */

Gets the object information of the class object.

Parameter

Description

pObject

Pointer to a VECTORSPLINE 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 VECTORSPLINE type and pass the address to this function. After modifying the vector object settings, call LVectorSpline::UnlockObject (). LVectorSpline::LockObject () and LVectorSpline::UnlockObject () should always be called in pairs.

Before an object has been added to the LVectorBase object, using LVectorBase::AddObject or LVectorLayer::AddObject, LVectorSpline::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 LVectorSpline::UnlockObject ().However, as long as the number of points does not change, the coordinates of the individual points can always be modified using LVectorSpline::UnlockObject ().

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

LvectorSpline::LockObject and LVectorSpline::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_TEXT

VECTOR_POLYDRAW

VECTOR_PIE

VECTOR_POLYDRAW

If an object type changes, LVectorSpline::LockObject and LVectorSpline::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:

LvectorSpline::UnlockObject

Topics:

Working with Vector Objects

Example

This example will add a new green bezier curve to the Active Layer LVectorBase object

Once added, the color will be changed to blue.

L_INT LVectorSpline__LockObjectExample(HWND hWnd, LVectorBase *pVector)
{
   UNREFERENCED_PARAMETER(hWnd);
   L_INT          nRet;
   VECTORSPLINE   Spline;
   //Create Spline Object
   VECTORPOINT        Points[4] = 
   {
            30,  30, 0, 0,
            30,  50, 0, 0,
            40,  60, 0, 0,
            10,  30, 0, 0,
   };
   Spline.nPointCount = 4;
   Spline.Point = Points;
   Spline.Pen.nSize = sizeof( VECTORPEN );
   Spline.Pen.bExtPen = FALSE;
   Spline.Pen.NewPen.LogPen.lopnStyle = PS_SOLID;
   Spline.Pen.NewPen.LogPen.lopnWidth.x = 10;
   Spline.Pen.NewPen.LogPen.lopnWidth.y = 10;
   Spline.Pen.NewPen.LogPen.lopnColor = RGB(0,255,0);
   LVectorSpline VectorSpline(&Spline);
   // add to current active layer
   LVectorLayer VectorLayer;
   nRet = pVector->GetActiveLayer(&VectorLayer);
   if (nRet == SUCCESS)
   {
      nRet = VectorLayer.AddObject(&VectorSpline);
      if(nRet != SUCCESS)
         return nRet;
      //Now change color to blue
      MessageBox(NULL, TEXT("Changing color to blue"), TEXT(""), MB_OK);
      VECTORSPLINE SplineTemp;
      nRet = VectorSpline.LockObject(&SplineTemp);
      if(nRet != SUCCESS)
         return nRet;
      Spline.Pen.bExtPen = FALSE; 
      SplineTemp.Pen.NewPen.LogPen.lopnColor = RGB(0,0,255);
      nRet = VectorSpline.UnlockObject(&SplineTemp);
      if(nRet != SUCCESS)
         return nRet;
   }
   else
   {
      MessageBox(NULL, TEXT("No Active Layer--Load a vector and run again"), TEXT(""), MB_OK);
      return nRet;
   }
   //LVectorSpline destructor called when VectorSpline goes out of scope
   return SUCCESS;
}