X-plane on an iPhone

If you’ve read my past reviews of X-plane, you’ll know that I’m somewhat of a fan of that product. It’s an ultra realistic flight simulator. If you’ll read the product page you will see that it boasts a long list of features. I can assure you, they’re being modest. I don’t pay for software very often but I’ve bought v8 and recently v9 of this one.

Anyway, I just had a little WTF moment reading this little blog post from Benjamin Supnik, one of the lead developers of X-plane who works on the scenery engine. They’ve actually ported X-plane to the iPhone! If so far, you didn’t think much of the iPhone as a development platform, look again. This is really impressive.

I just looked up the product page in iTunes and it has some nice screen shots. Of course they don’t ship the full UI or scenery. All you get is an area around Inssbruck (default area in the demo version of the normal version). Probably it is heavily tuned to work nicely on an iphone. However, the mere fact that they have it running at all is very impressive. Unfortunately, it’s not possible to link to product pages in iTunes, so you’ll just have to look it up yourself, producer is Laminar or you can go to Games->Simulation in the iphone section.

Also hilareous is Austin Meyer (founder and owner of Laminar that builds X-Plane) denying there was an iphone version of x-plane, just before he launched it on September 11th. A bit of a symbolic date for launching a flight simulator, don’t you think?

Sadly, I have no iPhone or ipod touch to play with. Working for Nokia and all that.

X-Plane 9 review

Last weekend I ordered X-plane version 9. I bought version 8 early 2006 and since then I haven’t looked back. Sure, MS Flight Simulator looks great but the flying sucks. Laminar consistently delivers with new features and bug fixes. Version 8 got its last major update (8.64) about half a year ago and since then they have been beta testing version 9. While I could have bought it earlier, I waited until they released it.

A few days ago the package with 6 double layer DVDs was delivered. Installation was not so smooth as I complained about here. But I managed to sort it out and have a working X-plane 9 now. I installed the European and US scenery. The 6 DVDs of world wide scenery is really nice and detailed but consists only of automatically computed landscapes from various databases. Europe now also includes the part I live in (Finland) which was too far north for version 8. However, I prefer to fly southern Europe, where the landscape is a bit more varied.

There are cities, forests, roads, airports, coastlines, etc. where they should be (and in surprising amount of detail) but the simulator lacks custom content like the massive amount of content that comes with Microsoft Flight simulator. To fix that, I installed the excellent Corsica scenery, which is one of the many third party scenery packages available and one of the first ones to be upgraded for version 9. This adds a nice level of realism. Flying in from Nice (another scenery package, warning horrible HTML layout) with the new Cirrus jet was pretty cool and surprisingly easy given that the Cirrus was new to me. According to the product announcement, this plane was actually created by Cirrus themselves and presumably tuned to their specifications and needs. Also, the 3D cockpit is pretty cool and much more user friendly on a PC than the average very complicated panel coming with a X-plane jet.

Technically, version 9 includes lots of improvements to the scenery rendering and simulation. The changes are outlined in great detail in the product announcement page by Laminar owner and founder, Austin Meyer. I have little to add here except to say that it mostly works and delivers as advertised. Don’t expect to max out any of the rendering settings, they have been designed such that this is not possible with any hardware available now. In fact they just raised the bar for future hardware. If you can get your hands on a NVIdia with a few GB of video ram, X-plane will probably find a use for every byte of it. The good news is that it still looks pretty good with object detail not set to “TOTALLY INSANE” (Austin Meyer loves his capitals). In case you are wondering, I have a three year old AMD 4400+ with 2GB and a NVidia 7800 GT. Anything similar or better will run X-plane just fine.

Part of the attraction of X-plane is that it is a niche product build by some dedicated people who know what they are doing and are totally focused on doing it. Considering that they have a very small programmer team and not much other people working for them, it is pretty amazing what they manage to deliver. They have to be smart and efficient about a lot of things. So their UI is totally custom and a bit wacky. But it works. The included planes are so so but there are plenty of free ones available to fix that (and some better ones for a small fee). With all these nice freeware planes out there (e.g. on x-plane.org), you have to wonder why the selection bundled with X-plane is so weak. Most of the planes don’t have 3D cockpits and quite a few even lack textures.

However, at the core of X-plane is an excellent and extremely detailed simulation of just about anything that flies and everything that makes it fly. I mean, they are worrying about the accuracy of the voltage in electrical systems here and how that behaves under different failure scenarios. The attention to detail is just amazing. This is a simulator made by absolute flight sim geeks for flight sim geeks. It has lots of rough edges but it does its core job extremely well and is arguably the best all round flight simulator available today.

Head tracking

I stumbled on two interesting programs that effectively turn my webcam into a head tracking device. The first one is a reasonably priced commercial package called Cachya. They have a trial version available that I installed to play with. The second one is a french open source product freetrack.

Why is this interesting?


(cachya, sightseeing)


(cachya, dogfight)


(freetrack)


(freetrack with a race game)

So, basically this stuff allows you to look around while flying around in your flight simulator. Since I spend quite some time in x-plane that is highly interesting.

Of course I installed both packages.

Freetrack is free but has one disadvantage: you need to attach a bunch of leds to your head for it to work. Since I don’t have any, am not planning a career as a Christmas tree and since the documentation is in French, I didn’t get very far with it. But it’s free and definitely tempting to give another try.

I also tried Cachya. It seems quite nice and doesn’t require any leds. Instead it works with a symbol that you can print out and attach to your cap. You will still look silly of course but not so bad as with a bunch of leds attached to your head. And considering the above videos, I might end up buying it. The only problem is that the trial version so far is not very convincing. A problem is that I have some nasty backlight from the window which tends to confuse it. Also I had lots of issues controlling the demo with my head. So altogether, I’m not quite ready to get my wallet out yet.

Then of course the expensive option is track-ir. This one apparently works but it is quite expensive and you still end up attaching reflectors to your head and connecting a bulky tracking device to your PC.

X-plane 8.50

A few months ago, I posted something about early betas of x-plane 8.50. Well the final version is here and seems to be working as advertised. A lot of feature work has been done in this release, much of it related to the simulation quality but also some nice improvements in the rendering engine.

I just took the Piper single propeller plane that comes with it for a flight from Marseilles to Paris Orly (after first flying from Nimes to Marseille with a custom Cessna 150). This is a nice flight because I have custom scenery for both ends of the flight. Also it’s a pretty long flight and it provides plenty of opportunity to play with various settings and fiddle with the ‘optimal’ throttle, mixture and prop ratio. The latter is pretty realistic because the simulator takes into account all kinds of variables to calculate speed, fuel consumption, oil pressure & temperature, etc (you name it, its there).
The flight was pretty uneventful except that I kept fiddling with the weather. Real weather was pretty awful (about 1 mile visibility) so that was not much fun in terms of visuals and my capabilities (not quite IFR capable yet :-). Also it was a good opportunity to put the new scenery loading logic to the test. Flying to Paris really is not fair because this happens to be 400 MB of custom version 7 scenery. A fresh startup of x-plane with the plane on Orly or Charles de Gaulles typically takes a few minutes longer just because of this scenery.

I’m happy to report that the in the background loading of scenery seems to be working pretty well. The simulator froze a couple of times for loading the stuff from disk (would be nice if that was done in the background as well). But aside from that no more freezes. All the texture loading (to the videocard) and other calculations seem to be taken care of by the second core on my dual core cpu. I think I experienced at most 20-30 seconds freezing overhead over the whole journey. The Paris scenery seemed to come in batches. First I flew into a really nasty ugly empty version 7 area (pretty ugly compared to the default v8 scenery) but then it got better as I got nearer to paris and more textures, 3d models, etc came in visual range. Orly looks great on approach. There were several warning messages about too much textures etc. This is partially due to my rendering settings and also to the fact that the scenery is pretty old stuff.

x-plane 8.50 beta

It seems Austin Meyer has had a busy summer. As you may know, I’m big fan of his flight simulator, x-plane. About three months ago it was upgraded from 8.30 to 8.40. The 0.10 version increment represented a huge list of new and improved features and he managed to throw in some nice performance enhancements as well. The upcoming 8.50 release has a changelist that is even more impressive.

Check it out here: http://x-plane.com/beta.html. The long list includes major improvements to the scenery rendering, simulation accuracy of the plane on the runway, simulation accuracy of other planes in the air (down to simulating the turbulance they cause in the atmosfere) and many minor improvements. The major scenery improvements I’ve been reading about on the scenery blog are just a footnote in this list. Just reading it will take quite some time. Imagine implementing all of that in three months! Anyway, I’m looking forward to trying out the new stuff. Particularly the visual enhancements and formation flying look like they could be fun.

sightseeing over paris

I’ve written quite a bit on x-plane lately. That was before I discovered a few good quality scenery packages. One of these packages is a 400 MB version of Paris, the capital of France. Wow. You can download it here, for free!
Here’s some screenshots (all running beautifully smooth). This is by far the most realistic and detailed scenery I’ve seen for any area in any flightsimulator. X-plane shows off it’s exceptional capabilities. Notice the detail in the background? All part of the scenery. This is typically where you’d see a mess of blinking pixels in ms flight simulator. It simply can’t handle that amount of detail. In x-plane all the screens below were with my default x-plane settings: render on graphics card, everything set to high except for roads and objects (default, see my earlier discussions), 4x anti aliasing. Framerate was excellent most of the time. I hit some bottlenecks while panning the view, otherwise everything stayed smooth and responsive.

Btw. this is a x-plane v7 scenery, not a v8 scenery. This means it is lacking some of the new features. Outside paris everything is the nice and default v8 scenery coming with x-plane.
arc de triomf.jpgEiffel tower and the SeineLe Louvre

Dutch Scenery for X-plane

NL X-Plane : a dutch scenery for X-Plane Sadly link now points to some shoe retail site. Obviously no longer exists 🙁

Just what I wanted. Nice scenery for x-plane. Despite weighing in at 60 GB, the world scenery coming with x-plane is a bit boring in some parts of the world. This is the fix for a small part of the world. The provided scenery for North Holland (region around Amsterdam) is quite well done. Flying at about 3000 feet lots of areas are clearly recognizable. Much better than the default scenery. Also quite nice compared to the nl2000 scenery for ms flightsimulator. Nl2000 is more detailed (in the number of objects mostly) and more polished of course. But then the ms flight simulator rendering engine is complete crap so you don’t actually see that much because everything is flickering all the time. X-plane on the other hand is above all smooth and allows you to see textured details in the distance.

more x-plane tweaking

I’ve finally found some optimal settings for my system. The number of objects in the view determines the framerate. X-plane includes an option to display render statistics including number of objects and framerate.

As a benchmark, I start x-plane, take off from jfk and make a turn towards Manhattan. As I make the turn, the worst case scenario in terms of the number of objects kicks in. Seeing the statistics change makes you understand the effect of various options.

My current options:

  • textures: extreme
  • anti-aliasing: 4x
  • resolution 1024×768 (in a window)
  • distance detail: very high
  • objects & roads: both default
  • compress textures: on
  • other options, set to default

The key options here are objects & roads. I’ve experimented with anti aliasing and objects setting whilst keeping an eye on the statistics. In the scenario above with the settings outlined above, I start out facing east (towards the atlantic) with about 2200 objects and 50 fps. As I take off, the number of objects increases to about 2500. Turning towards Manhattan the number goes up to 3600 and the framerate drops to about 25fps.

By changing the objects setting from default to lots (i.e. this comes after default and before tons, mega tons, too many and totally insane). As the names of these settings suggest, most of them are not realistic. going to lots from default means that the turn to Manhattan now drives the number of objects up to 10000. At the same time the framerate drops to 20 fps which is what (by default) is the level where x-plane starts reducing the visibility to keep the framerate up. In other words, you’re fogged in at 20fps. You can actually lower this number but less than 20 fps is not much fun. In fact I consider 25 to be the minimum for enjoyable flying.

Interestingly enough, the numbers are independent of the anti aliasing setting. Anti aliasing happens on the video card, which can easily handle it regardless of the number of object. I’ve disabled it, set it to 2x and set it to 4x. No difference (except visual quality). It’s purely a cpu thing. Somewhere around 8000 it becomes just to much for my poor amd x2 4400+. Too bad only one of the cores is used.

The settings above are a compromise between visual quality and number of objects. I’ve decided that most of the time, it is more important to be able to see every terrain feature in visual range (e.g. rivers, airports and mountains 20 miles away) than it is to see 10000 little cubes of various shapes with various textures in front of me. So I’ve maxed out texture settings & distance settings, turned on anti aliasing, compress textures and I am now seeing good framerates almost everywhere.

How it Flies

More playing with x-plane. I found this very nice reference on flying an airplane. I’ve learned quite a few useful things already. Just now, I made a silky smooth landing at JFK (New York) coming in at a nice and predictable 3 degree angle at a nice and predictable speed of 80 knots. That is largely due to reading the link above.

Landing at JFK

A few of the things that I have learned tonight (after practicing what I read in the first two chapters) is that there is nothing wrong with either my joystick or x-plane. The eratic pitch behaviour that I used to experience when flying x-plane, and to a lesser extent ms flightsimulator, was almost entirely due to my style of flying (or lack thereof). Correct the style and suddenly flight is as it is supposed to be. That in short is realism. In fact a real airplane would present you with similar (and dangerous) eratic pitch behaviour if you’d try to force your way down without much regard for what you should be doing to accomplish that goal.

I recommend anyone interested in flight (simulation) to spend some time reading the linked stuff. The material consists of a detailed discussion of the physical aspects of flying (e.g. exchanging airspeed for altitude). I’ve seen similar material before but this is a particular good reference in the sense that it provides a good conceptual overview of what is going on (i.e. the ‘how it flies’ part) and also provides valuable tips on how to translate the theory into practice. A basic understanding of physics helps (author is a physisist) but common sense goes a long way.

I was pleasantly surprised that the advice in the book actually works very well in x-plane. I’m now able to keep an airplane at a given altitude without pulling on the yoke all the time. Also I’m now able to effectively control and change airspeed without losing altitude or going into a controlled descent/ascent at the desired vertical speed. All of these are very important aspects of flying in a controlled way. It’s easy to just go full throttle all the time and sort of aim for the runway when landing whilst reducing throttle and extending flaps to sort of touch down without crashing. That’s different from taking off and landing properly. In real life, the latter will ensure you will probably survive the procedure.

x-plane graphics tweaks

Today I played a bit more with x-plane. I made two flights. One from Baltimore to Newark (with a King Air 350) and one from Philadelphia to Newark (Piper PA 180). Both planes were downloaded from xplane.org. More such goodies can be found there.

Additionally I played a bit with the graphics settings. What I found out was that the compress textures setting is really important. As noted in my previous post, the thing is mostly CPU bound. More objects require more CPU. However, with things like resolution and texture size, video ram is the bottle neck. Since I have a nice 7800 GT, there is 256 MB of memory. This may seem like a lot but there is quite a bit of textures in x-plane. Yesterday I found that it was impossible to set the texture size to extreme since that caused x-plane to reduce visibility to about a mile to keep up the framerate. Reason: I was running out of vram! The solution for that is compression, this is supported by the videocard and a common strategy for working with high resolution textures. Probably this should always be turned on unless the video card is really old.

With texture compression on (in the x-plane render settings), I can now have mega tons of objects, tons of roads (these are actual x-plane settings), extreme texture resolution and about ten AI planes in the air. That looks nice! Hundreds of textures have been included with the x-plane global scenery and they are quite good (compared to e.g. the shit that comes with ms flightsimulator).

With these settings, flying over New York is workable (though framerate suffers a bit). Outside of the cities, the number of objects is much less of a problem. Besides, most cities are quite a bit smaller than NY.

screenshot NY
Another thing I noticed is that the scenery in europe does not appear to include objects. So flying outside of the US is a lot less fun. The Alps though are very detailed. Here the lack of winter textures makes them look unrealistic though. This time of year they should all be snow covered and even in the summer some of them remain snow covered. Not in x-plane. I suppose that is the limitation of the approach taken by the global scenery people (no custom modelling, only take in data from sources like satellite images). However, europe is still 4.7GB of data. Most of this data concerns data coming from various satellite images (high detail). Things like rivers, coastlines, terrain types and elevation are all accurate. So even though Amsterdam does not have objects, it still has the right textures in the right place so you can see where the city ends.