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L_VecEnumObjectsInLayer

Summary

Enumerates all objects inside a vector layer.

Syntax

#include "ltvkrn.h"

L_LVKRN_API L_INT L_VecEnumObjectsInLayer(pVector, pLayer, pEnumProc, pUserData, dwFlags)

Parameters

pVECTORHANDLE pVector

Pointer to a vector handle.

const pVECTORLAYER pLayer

Pointer to a vector layer. The objects inside this layer will be enumerated. If this parameter is NULL, objects inside the current active layer in the vector handle will be enumerated.

pVECTORENUMOBJECTSPROC pEnumProc

Pointer to the callback function used to enumerate the vertices within the vector handle. The callback function must adhere to the function prototype described in VECTORENUMOBJECTSPROC.

L_VOID * pUserData

Void pointer that you can use to pass one or more additional parameters that the callback function needs.

To use this feature, assign a value to a variable or create a structure that contains as many fields as you need. Then, in this parameter, pass the address of the variable or structure, casting it to L_VOID *. The callback function, which receives the address in its own pUserData parameter, can cast it to a pointer of the appropriate data type to access your variable or structure. If the additional parameters are not needed, you can pass NULL in this parameter.

L_UINT32 dwFlags

Flag that indicates which objects to enumerate. Possible values are:

Value	Meaning
0	Enumerate all objects in the layer.
VECTOR_FLAGS_SELECTED_ONLY	Enumerate only selected objects in the layer.

Returns

Value	Meaning
SUCCESS	The function was successful.
< 1	An error occurred. Refer to Return Codes.

Comments

Required DLLs and Libraries

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

Example

This example will select all objects inside the current active layer.

static L_INT EXT_CALLBACK EnumObjectsProc(pVECTORHANDLE   pVector, 
                                          pVECTOROBJECT   pObject, 
                                          L_VOID*         pData ) 
{ 
   L_INT nRet; 
   VECTOROBJECT ObjectDesc; 
 
   UNREFERENCED_PARAMETER( pData ); 
 
   /* Select the object */ 
   nRet = L_VecGetObject( pVector, pObject, VECTOR_OBJECT, &ObjectDesc ); 
   if(nRet != SUCCESS) 
      return nRet; 
 
   ObjectDesc.dwFlags |= VECTOR_OBJECT_SELECTED; 
   nRet = L_VecSetObject( pVector, pObject, VECTOR_OBJECT, &ObjectDesc ); 
   if(nRet != SUCCESS) 
      return nRet; 
 
   nRet = L_VecFreeObject( VECTOR_OBJECT, &ObjectDesc ); 
 
   /* Continue the enumeration */ 
   return nRet; 
} 
 
L_INT VecEnumObjectsInLayerExample(pVECTORHANDLE pVector) 
{ 
   L_INT nRet; 
 
   /* Enum all objects inside the current active layer */ 
   nRet = L_VecEnumObjectsInLayer( pVector, NULL, (pVECTORENUMOBJECTSPROC)EnumObjectsProc, NULL, 0L ); 
 
   return nRet; 
}