FSX C: Vars and how to set it up

[cheangjc]

Hi,

I am currently playing with C++, learning to get to grips with internal C++ to XML Var interaction.

I have successfully read/write L: Vars, but am now looking to see how to let a XML gauge read a C: Var.

(C:MyGauge:Varname,unit) is the syntax from what I understand.

However, I do not know what Mygauge is; Is it the GAUGE_NAME as declared or is it the file name?

Also, How do I set up a C: Var in the C++ gauge, do I have to register with the panel service or something similar to L:Var?

Thanks in advance for any help given

 

[taguilo]

You can't read C++ .gau/dll vars from an XML gauge.
I see you are confusing C: vars ("Custom") which are XML-type vars managed from a dll module (not gauge). in your (C:MyGauge:Varname,unit), what you call MyGauge is in fact the name of a C++ class.
I suggest you check the Panel and GaugesSDK, Mixed Mode folder, Cabin_Comfort example.
And to read a C:Var type in a C++ gauge you're right, first need to register it. Also is a bit more tricky than in XML.

Tom

 

[n4gix]

XML cannot "read" C variables at all.

You need to pass the value of any C variable to an XML L:var...

In the PRE_UPDATE case:

xml_SND1_id = check_named_variable ( "XMLSND1" ) ;
xml_SND1 = get_named_variable_value (xml_SND1_id);

To pass any changes from the C variable to the XML L:var use the set_ construct:

set_named_variable_value(xml_SND1_id, xml_SND1) ;

 

[cheangjc]

Mmmmm. Looks like I have indeed misunderstood that C: Vars can be used in gauges. I basically needed that for String Vars, but I will have to figure an alternative.

Thanks for both of your inputs.

 

[taguilo]

But of course C:Vars can be read/written in .gau/dll gauges.

From your statement I understand you need to read XML string vars (like XMLVars or fs9gps) within C++ gauges. Or maybe others?

If you post some details I can give you an example for both.

Tom

 

[cheangjc]

But of course C:Vars can be read/written in .gau/dll gauges.

From your statement I understand you need to read XML string vars (like XMLVars or fs9gps) within C++ gauges. Or maybe others?

If you post some details I can give you an example for both.

Tom

Hi,

It can? Well, I just tried the Cabin Comfort Code into the a dll gauge and there was no output: (blank or 0)

I would appreciate the example for the C: var in a dll gauge.

 

[taguilo]

This is an example on how to retrieve GPS C: variables.

http://www.fsdeveloper.com/forum/showpost.php?p=378156&postcount=10

For another Custom class, ie XMLVARS, you must replace "fs9gps" in the register_callback functions with "XMLVars".

Bear in mind that if you want to share those C: vars with XML gauges, you'll need to define the source C++ variables in the dll module (like Cabin_comfort.dll) as PUBLIC, and manage the code to handle the exchange process properly.

Tom