MSFS20 Reading an aircraft string using execute_calculator_code issue

[mariomotta]

This piece of code, that will be compiled as wasm, does not return ATC _ID as should do:

PCSTRINGZ barcode;
execute_calculator_code((PCSTRINGZ)"(A:ATC ID, string)", (FLOAT64*)NULL, (SINT32*)NULL, &barcode);

barcode is unreadable..
Any clues ?
Thanks in advance
/Mario

 

[WarpD]

It is not a PCSTRINGZ... it's 64-bit code for MSFS2020 and that probably means wide characters... like WCHAR

 

[mariomotta]

Thanks for answer,
at least has such declaration in gauges.h:

BOOL FSAPI execute_calculator_code(PCSTRINGZ code, FLOAT64* fvalue, SINT32* ivalue, PCSTRINGZ* svalue);

using std:wstring or any other WCHAR object won't compile.
Do you have any working example using wide chars strings ?

 

[WarpD]

All I can offer is that what you are describing sounds like a WCHAR* being referenced as a char*... I know that in P3D v4 (the 64-bit), it was changed from PCSTRINGZ to LPCSTR which isn't a wchar... BUT... the results you're saying you are getting remind me of a WCHAR* being referenced as a char*.

 

[mariomotta]

Thanks,
however also in p3d v5 execute_calculator_code has the same signature as above, moreover same code works flawlessly in P3D 64 bit.
/Mario

 

[WarpD]

I probably shouldn't have mentioned P3D... creates confusion and it's not even the same code path. Try to cast the returned pointer value as a WCHAR* and see if it makes a difference.

 

[mariomotta]

nope, always a void string is returned :-(

 

[Prepar3DGuy]

I have also receive empty string "\0" for every variable from Aircraft String Data and also from some another having Units string.
SimVar watcher example from SDK doesn't have string units and that is strange.
I think that lack of XML explanation in SDK documentation can't explain what execute_calculator_code can and can not do in MSFS with strings.

 

[mariomotta]

Hello,
same thing happens with:

SimConnect_AddToDataDefinition(hSimConnect, DEFINITION_1, "TITLE", NULL,SIMCONNECT_DATATYPE_STRINGV);
SimConnect_RequestDataOnSimObject(hSimConnect, REQUEST_1, DEFINITION_1, SIMCONNECT_OBJECT_ID_USER, SIMCONNECT_PERIOD_ONCE);
.....
case SIMCONNECT_RECV_ID_SIMOBJECT_DATA:
      {
        SimConnect_RECV_SIMOBJECT_DATA *pObjData = (SimConnect_RECV_SIMOBJECT_DATA*)pData;
           switch(pObjData->dwRequestID)
        {
          case REQUEST_1:
                   char* pS = (char*)&pObjData->dwData;
            break;
        }
      break;
      }

returns a void string for all aircraft string with no exception, while works nicely on other data types.

 

[WarpD]

Variable length strings have to be processed differently than static length strings. You have to use SimConnect_RetrieveString to process a variable length string.

 

[mariomotta]

Thanks, however won't work with aircraft fixed strings neither but will try this.
/Mario

 

[WarpD]

If you're doing this in MSFS2020... then it's probably non-functional, like most of the SDK for aircraft support.

 

[mariomotta]

Thanks,
as suspected from MSFS 2030 SDK:
String SimConnect_RetrieveString Bad response Returns empty strings (either a data or server problem)
/Mario