After mentioning which types of variables can and can't be set in my last post, I was feeling a little guilty. In the FS2004 SDK we didn't actually define which types of variables CAN be set. So here's an improved table of variable types, since the SDK docs were deficient. Speaking of which, I would love to get out a completely updated doc for the XML gauges, but seeing as a good bit of work needs to be done there, it might be a while before such an update takes place.
Parameter
Stands for…
Read-only?
Units required?
Description
A
Aircraft
Yes
Yes
Get the current parameters of the aircraft
C
Custom Gauge
No (in some cases)
No
To use these variables, a separate C++ module must be written and loaded by flight sim. The fs9view and fs9gps are currently the only gauge modules that use this feature.
E/P
Environment/Program
Yes
Yes
Environment and Program-related parameters include time of day and simulation rate. (Either E: or P: may be used).
G
Gauge variable
No
No
General-purpose user-defined variable local to a particular gauge.
K
Key code
No
No
Key codes that are sent from gauges to Flight Simulator.
L
Local
No
Yes
General-purpose, user-defined variable that can be accessed by multiple gauges.
M
Mouse variables
Yes
No
Reports the state of the mouse for use in mouse click handlers.
R
Resource strings
Yes
No
Get a string from the resource file (which will be localized). E.g. (R:HELPID_GAUGE_FLAPS_UP) See helpids.doc for a complete list of strings
I haven't yet seen this information posted online anywhere, but if anyone knows of any resources out there that cover topics such as this, let me know so I can add links to them!
Scrabble fans: Bonus points if you can make a word (in any language) from the letters (ACEGKLMR) that define the different variable types ...