RE: [v8i MDL C++] MDL works in Debugging-mode, but crashes outside of Debugging!?

Hi Jon,

I tried both: Choosing and loading the MDL from the MDL-Menu and by command-line "MDL Load <mdl-Name>", but the result is the same (that Microstation crashes).

It's a tricky problem to solve without sitting beside you to see your code and computer.  Could it be a timing issue?  What does your code do in MdlMain()?

I don't know what you mean with "Timing issue", but I will try to explain shortly what happens.

Here is the MdlMain-Code:

 extern "C" DLLEXPORT int MdlMain (int argc, char *argv[])
{
 RscFileHandle     rfHandle;
 SymbolSet   *setP;  
 mdlResource_openFile (&rfHandle, NULL, FALSE); 
 setP = mdlCExpression_initializeSet (VISIBILITY_DIALOG_BOX, 0, FALSE);
 mdlDialog_hookPublish (sizeof(uHooks)/sizeof(DialogHookInfo),uHooks);
 mdlDialog_publishBasicVariable   (setP, mdlCExpression_getType(TYPECODE_DOUBLE), "current_x", &current_x);
 mdlDialog_publishBasicVariable   (setP, mdlCExpression_getType(TYPECODE_DOUBLE), "current_y", &current_y);
 mdlDialog_publishBasicVariable   (setP, mdlCExpression_getType(TYPECODE_DOUBLE), "current_z", &current_z);
 initSurface(); 
 mdlDialog_open (NULL, DIALOGID_Coord);
 return (SUCCESS);
}

The published variables "current_x/y/z" are used to Show the user the actual coordinates of the mouse.

I assume, that the problematical function is the "initSurface"-function which loads a complex structure from an ASCII-file into a global variable of this structure, which is used later to make some calculations wether the mouse (= current coordinates) are in or outside certain Areas. For this complex structure there is dynamic Memory-allocation necessary.

I have now two different Versions for the MDL, one that works with the C++ functions "new" and "delete" for the Memory-handling (which has this strange behaviour only to run in Debugging-mode) and another Version that uses the MDL-functions "dlmSystem_mdlCalloc" and "dlmSystem_mdlFree" instead of the C++-functions, because I thought, that this would solve the Problem.

The class for the complex structure and the connected member-function itself (including reading from file, calculation of inside/outside Areas ...) in C++-Version was tested outside MDL and Microstation-surrounding in Visual Studio 2005 and worked fine.

The second Version with the MDL-functions for Memory-handling crashes in Debugging-mode at the Point were there are type-casts done.

From the Basic-class "CBasicGeometry" there are derived classes e.g. "CTriangle" . Inside the structure there is a pointer to an Array of CBasicGeometry-elements:

...
 int  numbasic;           //Number of CBasicGeometry-objects
 CBasicGeometry **pBasic; //Pointer to vector of pointers to CBasicGeometry-objects
...


Inside the overloaded "Operator ="-function there is e.g. a type-cast necessary as follows:

...
   case 300:    //CTriangle-element
   //pBasic[i]=new CTriangle;     //C++
    pBasic[i]=(CTriangle*) dlmSystem_mdlCalloc(1, sizeof(CTriangle));    //v8i-MDL 
    (static_cast<CTriangle*>(pBasic[i]))->operator = (static_cast<const CTriangle&>(*psurf.pBasic[i]));    //here it crashes, although this worked fine in C++
    break;
...


Is there a Special MDL-function for type-conversions necessary instead of the C++ cast-functions?

Many thanks for you help and best regards,

Ines Wieland