By way of example, here's a patch to make the position init code (in fg_init.cxx) cleaner, partly thanks to the FGPositioned changes. It reduces the file size by 200 lines - virtually all of which was copy-and-paste. Once the remaining class (FGAirport) is converted to inherit FGPositioned, all the future patches should be like this - touching one or a few files at most.
This factors the start-offset logic out into a helper, which also does the final property setting (which has to happen on both the /preset and 'real' values). Using the accessors in FGPositioned, and the offset helper, a couple of cases become trivial (fix and nav) and others become much simpler.
Convert FGNavRecord to inherit FGPositioned. This is much more self-contained than the FGRunway change, since FGNavRecord already had good encapsulation of its state. However, it's a large diff due to moving around two nasty pieces of code - the 'align navaid with extended runway centerline' logic and the 'penalise transmitters at the opposite runway end' logic.
In general things are more readable because I've replaced the Navaid type enum, and the use of Robin's integer type codes, with switches on the FGPositioned::Type code - no more trying to recall that '6' is an outer marker in Robin's data. The creation code path is also pushed down from navdb into navrecord itself.
Convert FGRunway to be heap-based, and inherit FGPositioned. This is a large, ugly change, since FGRunway was essentially a plain struct, with no accessors or abstraction. This change adds various helpers and accessors to FGRunway, but doesn't change many places to use them - that will be a follow up series of patches. It's still a large patch, but outside of FGAirport and FGRunway, mostly mechanical search-and-replace.
An interesting part of this change is that reciprocal runways now exist as independent objects, rather than being created on the fly by the search methods. This simplifies some pieces of code that search for and iterate runways. For users who only want one 'end' of a runway, the new 'isReciprocal' predicate allows them to ignore the 'other' end. Current the only user of this is the 'ground-radar' ATC feature. If we had data on which runways are truly 'single-ended', it would now be trivial to use this in the airport loader to *not* create the reciprocal.
Here's part 2 - converting FGFix (the simplest one) to be both heap-based and inherit FGPositioned. One minor benefit from this is replacing some dangerous code in FGFixList which used to return the address of an iterator member ('&it->second'). To keep the diff a sensible size, I'm not updating the callers to use the richer FGPositioned types - i.e replacing separate lat/lon handling with SGGeod. I will make those cleanups, but in future patches.
If someone could kindly apply the attached patch, that'll keep this from crashing, I believe. The fix is easy since FGAirport can now always provide an active runway - there's no need to guess at random, or rely on the tower having set one up.
Small patch fixing bugs I've encountered while getting the current CVS to build in MSVC.
* std::lower_bound was used with the key-type of a map, but lower_bound expects the value-type of the collection it works on, with is std::pair. MSVC seems to be more strict about this.
* Added an missing include statement.
* Replaced an rint() call with floor() (MSVC does not offer rint).
Here is a little patch that changes the behaviour of the VOR CDI and OFF-flag
for indicators like the HSI when getting outside the range of the VOR
station.
Currently, when flying at a distance between the effective_range and twice the
effective_range of a VOR station, the in-range property is computed based on
a random value, causing the OFF Flag and the CDI bar to perform an ugly
jitter.
The attached patch introduces a new property signal-quality-norm which is
computed based on the distance to the station and the range. It is 1.0 when
the distance is less than the range and decreases by 1/x^2 for distances
greater than the range leading to a signal-quality-norm of 0.25 for distances
two times the range, 0.125 for three times the range and so on.
The in-range flag is tied to a signal-quality-norm greater than 0.2 (fixed
squelch).
The CDI and GS needle deflection is multiplied with the signal-quality-norm.
The benefit is:
- Ability to animate the OFF-Flag with a smooth transition.
- CDI and GS needle deflection shows correct values when in range
(signal-quality-norm=1.0) and show some wrong indication when the range is
exceeded
- CDI and GS needle start to move, even when the OFF flag is visible
- No more jitter for flag and needles
See the new SenecaII ki525a hsi as an example at
http://www.t3r.de/fg/navpatch.jpg
The numbers on the image are:
(1) the new property signal-quality-norm
(2) distance exceeds the effective-range by 30%
(3) NAV flag has a rotation animation bound to signal-quality-norm and is
partially visible
(4) CDI is partially deflected even with NAV flag shown
This implementation better matches reality - at least, how I observed it ;-)
Good news: I'm working on some automatic testing of the 'core' FG pieces, especially those I'm likely to break in my Navaids / airports / runways work
Bad news: I already broke something, in my runways refactoring. (But my tests caught it!)
Attached patch fixes it - it's (of course) the stupidest thing in the world. Incidentally, standardising this kind of code into some (inlined) header is becoming more and more of a priority for me - I've lost count of the number of times I've seen the 'clamp heading to 0..360.0' and 'reverse a heading and clamp it' idioms in the code. The KLN89 and MkVIII code have (of course) their own helpers for this.
This is a little intrusive on the KLN89 code, but avoids the wasteful cloning of the airports, runways and navaids which current happens, and also combines the ugly string ordering code.
- removes various members from FGRunway which no-one was using
- any of these can be trivially re-instated if and when someone
actually wants to use them - but right now they're simply bloating up
FGRunway, which we have lots of, because it currently includes all the
taxiways in Robin's data.
- that's it.
- Runways are now part of an airport, instead of a separate list
- Runways are no longer represented as a boring struct, but as a class
of their own.
-Improved runway access to unify various runway access methods.
use <enabled>false</enabled> flag for widgets that shouldn't be drawn
instead of <hide>true</hide>. This is consistent with other places
in fgfs, like menu entries, hud elements, subsystem switches, etc.
