FSX better description for Token Variables

Mellin · 9 Apr 2016

Hi!

I'm working on some c++ gauges for my glider but I have a problem:
I lack information on units used by Token Variables: https://msdn.microsoft.com/en-us/library/cc526959.aspx

Some of them act in a weird way, eg:
I was working on a communication radio and for unknown reason Token Variables "COM_FREQUENCY" and "COM_STBY_FREQUENCY" give me: 10288 and 10277

When in VR cockpit, "COM ACTIVE FREQUENCY:1" and "A:COM STANDBY FREQUENCY:1" give me: 128.30 and 128.25

Is there a place where I can find more detailed description on them?

ddawson · 9 Apr 2016

They're being returned as binary coded decimals. The leading '1' is dropped; you'll see the remaining digits if you display the result as a hex number. If you search this sub-forum, I'm pretty sure you will find a discussion or two on how to convert the result to something useful.
I've always just used SimConnect or execute_calculator_code if I needed to retrieve a com frequency.

Doug

taguilo · 9 Apr 2016

ddawson said:
I've always just used SimConnect or execute_calculator_code if I needed to retrieve a com frequency.

Adding to Doug's comment I believe that, to retrieve simulation variables (AKA AVars), is much simpler to use aircrat_varget and associated functions instead of token vars, mostly because of the possibility to express their values in different units without having to write conversion formulas.

Tom

n4gix · 9 Apr 2016

See the Wiki for examples:
http://www.fsdeveloper.com/wiki/index.php?title=C:_XML_Variables_in_C_Gauges
-or-
http://www.fsdeveloper.com/wiki/index.php?title=C:_Decimal_to_BCD

taguilo · 9 Apr 2016

An example on what I use to retrieve AVars in C++ :

In a header (.h) file:

Code:

FLOAT64 AVar(PCSTRINGZ szName,UINT32 iIndex,PCSTRINGZ szUnits)
{
    return aircraft_varget( get_aircraft_var_enum(szName),
                get_units_enum(szUnits),iIndex);
}

And to get the value:

Code:

FLOAT64 fCom1Freq = AVar("COM ACTIVE FREQUENCY",1,"Mhz");

The second parameter is an index to engine, or radio unit (1,2,3,etc.). Vars that do not have an index must pass 0 here.

Tom

Mellin · 10 Apr 2016

Let me know if I understand:

I put that first code to gauges header file (in case of SDK example it would be gauges.h file).
And then I use

Code:

AVar("COM ACTIVE FREQUENCY",1,"Mhz")

in callback code of a eg.: MAKE_STRING, like this:

Code:

FLOAT64 fCom1Freq = AVar("COM ACTIVE FREQUENCY", 1, "Mhz");

    return fCom1Freq;

Am I right?

taguilo · 10 Apr 2016

Mellin said:
I put that first code to gauges header file (in case of SDK example it would be gauges.h file).

Do not touch gauges.h. Instead, if you don't have a custom header file for that gauge, you can declare the function at the top of the code and write its content at the bottom for clarity:

Code:

....
extern PELEMENT_HEADER temperature_list;
extern MOUSERECT temperature_mouse_rect[];

FLOAT64 AVar(PCSTRINGZ szName,UINT32 iIndex,PCSTRINGZ szUnits);

GAUGE_HEADER_FS700(etc....);
...
....
FLOAT64 FSAPI Com1_string_cb( PELEMENT_STRING pelement )
{

    FLOAT64 fCom1Freq = AVar("COM ACTIVE FREQUENCY", 1, "Mhz");
    wsprintf(pelement->string, "%3.2f", fCom1Freq);   // format option
    return fCom1Freq;

}
...
MAKE_STRING(etc,etc)
...
.....
FLOAT64 AVar(PCSTRINGZ szName,UINT32 iIndex,PCSTRINGZ szUnits)
{
    return aircraft_varget( get_aircraft_var_enum(szName),get_units_enum(szUnits),iIndex);
}

Hope this helps.

Tom

Mellin · 10 Apr 2016

Thank you for the tip!

Although I think I'm making some other mistakes.

When I load it, in cockpit view, string shows "F".

I deleted that (and only that) entery from gauges.h file, that I have put there for test.

Beginning of my gauge:

Code:

char radio_gauge_name[] = GAUGE_NAME;
extern PELEMENT_HEADER        radio_list;
extern MOUSERECT            radio_mouse_rect[];

FLOAT64 AVar(PCSTRINGZ szName, UINT32 iIndex, PCSTRINGZ szUnits);

GAUGE_HEADER_FS700(GAUGE_W, radio_gauge_name, &radio_list, \
    radio_mouse_rect, 0, 0, 0, 0);


#define RADIO_GAUGE_CHARSET                DEFAULT_CHARSET
#define RADIO_GAUGE_FONT_DEFAULT            "Quartz"
#define RADIO_GAUGE_WEIGHT_DEFAULT        FW_NORMAL

That string:

Code:

FLOAT64 FSAPI    radio_com_string_cb(PELEMENT_STRING pelement)
{
    FLOAT64 fCom1Freq = AVar("COM ACTIVE FREQUENCY", 1, "Mhz");
    wsprintf(pelement->string, "%3.2f", fCom1Freq);   // format option
    return fCom1Freq;
}

MAKE_STRING
(
    radio_com_string,
    NULL,
    radio_fail,
    IMAGE_USE_ERASE | IMAGE_USE_BRIGHT | IMAGE_USE_TRANSPARENCY,
    0,
    103, 61,
    60, 20,
    10,
    COM_FREQUENCY,
    DISPLAY_UNITS,
    MODULE_VAR_NONE,
    RGB(255, 255, 255),
    RGB(0, 0, 0),
    RGB(92, 92, 92),
    RADIO_GAUGE_FONT_DEFAULT,
    RADIO_GAUGE_WEIGHT_DEFAULT,
    RADIO_GAUGE_CHARSET,
    0,
    DT_CENTER | DT_VCENTER | DT_SINGLELINE,
    NULL,
    radio_com_string_cb
)

and the end:

Code:

MOUSE_END


//test XML value
FLOAT64 AVar(PCSTRINGZ szName, UINT32 iIndex, PCSTRINGZ szUnits)
{
    return aircraft_varget(get_aircraft_var_enum(szName), get_units_enum(szUnits), iIndex);
}
/////////////////////////////////////////////////////////////////////////////
#undef GAUGE_NAME
#undef GAUGEHDR_VAR_NAME
#undef GAUGE_W

Maybe I should put C"NULL," instead of "COM_FREQUENCY," in the MAKE_STRING?

taguilo · 11 Apr 2016

Make the 3 var lines as MODULE_VAR_NONE, then try this format for the callback:

Code:

FLOAT64 FSAPI radio_com_string_cb(PELEMENT_STRING pelement)
{
   FLOAT64 val=pelement->source_var[0].var_value.n;
   val = !val;
  
   FLOAT64 fCom1Freq = AVar("COM ACTIVE FREQUENCY", 1, "Mhz");
   wsprintf(pelement->string, "%3.2f", fCom1Freq); // format option
  
   return val;
}

Should work now, or almost.

Tom

Mellin · 11 Apr 2016

No effect.
I have changed font for Arial and it is not "F" but "f".

Current code:

Code:

FLOAT64 FSAPI    radio_com_string_cb(PELEMENT_STRING pelement)
{
    FLOAT64 val = pelement->source_var[0].var_value.n;
    val = !val;

    FLOAT64 fCom1Freq = AVar("COM ACTIVE FREQUENCY", 1, "Mhz");
    wsprintf(pelement->string, "%3.2f", fCom1Freq); // format option

    return val;
}

MAKE_STRING
(
    radio_com_string,
    NULL,
    radio_fail,
    IMAGE_USE_ERASE | IMAGE_USE_BRIGHT | IMAGE_USE_TRANSPARENCY,
    0,
    103, 61,
    60, 20,
    10,
    MODULE_VAR_NONE,
    MODULE_VAR_NONE,
    MODULE_VAR_NONE,
    //COM_FREQUENCY,
    //DISPLAY_UNITS,
    //MODULE_VAR_NONE,
    RGB(255, 255, 255),
    RGB(0, 0, 0),
    RGB(92, 92, 92),
    RADIO_GAUGE_FONT_DEFAULT,
    RADIO_GAUGE_WEIGHT_DEFAULT,
    RADIO_GAUGE_CHARSET,
    0,
    DT_CENTER | DT_VCENTER | DT_SINGLELINE,
    NULL,
    radio_com_string_cb
)

WarpD · 11 Apr 2016

wsprintf is the culprit. use sprintf instead... it's not a widechar string.

Mellin · 11 Apr 2016

Thanks for a tip.

I'm sorry but I'm apartamenty dumb.
I changed the callback code to:

Code:

FLOAT64 FSAPI    radio_com_string_cb(PELEMENT_STRING pelement)
{
    FLOAT64 val = pelement->source_var[0].var_value.n;
    val = !val;

    FLOAT64 fCom1Freq = AVar("COM ACTIVE FREQUENCY", 1, "Mhz");
    char buffer[200];
    sprintf(buffer, "%d", fCom1Freq);

    return val;
}

and now it won't even build.

Someone please tell me how dumb I am and what have I done wrong here.

ddawson · 11 Apr 2016

Try:
FLOAT64 FSAPI radio_com_string_cb(PELEMENT_STRING pelement)
{

FLOAT64 fCom1Freq = AVar("COM ACTIVE FREQUENCY", 1, "Mhz");
sprintf(pelement->string, "%3.2f", fCom1Freq); // format option

return 0.;
}

Mellin · 11 Apr 2016

Again error while building:
"C3861 'sprintf': identifier not found"

ddawson · 11 Apr 2016

You do need to #include <stdio.h>

Mellin · 11 Apr 2016

OMG!!!!
It worked!

Thank you ddawson so much.

My thanks go also to any and all people who helped my with it!

Mellin · 11 Apr 2016

A problem (not related to coding but understanding value of variables):
XML tooltip "TOOLTIPTEXT_XPNDR_REPORTED_FLT_LVL" gives me code "FL004" from:

Code:

FL%( (A:PLANE ALTITUDE,feet) 1000 / (A:SEA LEVEL PRESSURE,inHg) - 29.92 + 10 * )%!03d!

I tried to recreate that code in callback code:

Code:

FLOAT64 ftransponser1 = AVar("PLANE ALTITUDE", 0, "feet") / 1000;
    ftransponser1 = ftransponser1 - AVar("SEA LEVEL PRESSURE", 0, "inHg");
    ftransponser1 = ftransponser1 + 29.92;
    ftransponser1 = ftransponser1 * 10;
    sprintf(pelement->string, "FL%3f", ftransponser1);

but it gives me "FL3.65".

Any ideas?

taguilo · 11 Apr 2016

Check formatting tags. To mimic the tooltip text, try:

sprintf(pelement->string, "FL%03d", (UINT32)ftransponser1);

Tom

Mellin · 11 Apr 2016

Much better.
It gives me "FL003", but original XML still gives "FL004".
Maybe it's a problem with shortening of number.

taguilo · 11 Apr 2016

Then try without converting the variable, it should round to 004

....

Tom