This document contains tips for making better Gateway airports. Situations vary, and these suggestions may not apply in all instances.
The X-Plane terrain mesh in the vicinity of airports is dependent on the geographic region, and also the airport boundary that existed at the time the LAST mesh cut occured. Mesh cuts are very infrequent, and usually occur at the start of a new X-Plane release (eg XX-Plane 10, X-Plane 11, etc).
Airport boundaries do the following:
- Flattening of the terrain
- Injection of airport-plausible terrain
- Exclusion of autogen (except roads/power lines)
Boundaries have no effect on the airport PRIOR to the next mesh recut, so we inject them with an eye on the future, and not the present.
Urban Airport Boundaries
In urban environments, it usually makes sense to draw the airport boundary relatively close to the contours of the airport itself, like this:
Rural Airport Boundaries
In less-urban, or rural environments, it often makes sense to draw a boundary that is less tightly contoured, like this:
Boundaries are open to a degree of interpretation. Use these where you want terrain flattening and plausible airport-terrain to occur, and also where you want autogen suppression.
Boundaries determine the terrain mesh that will exist in the vicinity of an airport in the FUTURE. However, this may be a long time from now, and from a pragmatic perspective we want the airport to look good today!
A well-crafted airport can be let down by the underlying mesh – like this:
This can be solved with a manual injection of the appropriate terrain polygon – like this:
Choosing the right terrain polygon is crucial, as many of the available selections in WED render very poorly – we want to avoid this:
and instead target something like this:
Choosing the appropriate terrain polygon often requires trial and error – but here are some nice ones that may save you some time:
Integrating Terrain Polygons
No facility currently exists to ‘soft-blend’ the edges of terrain polygons, and this can be a problem if they are to look plausible at airports.
One technique that often works to disguise this problem is to take advantage of nearby road-networks. This can be a time-consuming process, as the road networks in X-Plane often do not precisely match the location of the real roads that are visible in WEDBing and other satellite imagery available in WED. However, the results are often quite pleasing – and well worth the time invested:
In this example, the edge of the custom terrain polygon has been placed precisely underneath the road, and hence the ‘hard’ edge is hidden from view.
Injecting Missing Terrain
The default mesh in X-Plane does a good job of covering nearly the entire planet with a reasonable degree of accuracy. However, sometimes the mesh does not include man-made projections into the water, and at other locations the mesh may be missing entirely.
When building airports at locations with compromised mesh, it’s tempting to inject a ‘quick and dirty’ terrain polygon – like this:
However, straight edges like these are rarely found in nature, and this also tends to emphasize the fact that the polygon is two-dimensional – because the terrain elevation is zero.
A better method is to randomize the edge of the polygon:
Injecting a second polygon at the demarcation between the land and water further enhances the effect:
If the terrain is a man-made projection, incorporating the ‘Embankment’ facade (X-Plane 11.30 and later) is very pleasing:
Use only the latest facades
The addition of the Terminal Kit to X-Plane 11.10 was a major step forward for Gateway airports. These facades are of a much higher quality than the older terminal facades, and also provide the artist with a great deal more ‘architectural’ capability.
It is highly recommended to replace old terminal facades in any airport project with the nearest equivalent in the Terminal Kit. Here are two examples:
Older Terminal Facade:
Terminal Kit Facades:
Be sure to check out the Terminal Kit manual for more information.
Facades that exist principally for autogen purposes provided, until recently, the only means to create high-rise / non-terminal structures at airports. Because these were not designed for close-inspection, they have lower-quality textures that also appear blurry when stretched.
New generic facades were recently created for the Las Vegas strip landmarks package that was injected into X-Plane 11.25. These are excellent for the creation of non-terminal structures at airports.
Use only these newer facades at airports. Check out this link for more info:
New options for Adjustable Jetway creation were included in X-Plane 11.20. These are far superior to the old ‘fixed’ objects, both in terms of rendering quality, and also the flexibility to create exactly what you need. Additionally, these will implicitly support dynamic jetways in the future, when this capability is added.
There is probably never a case that can be made to use the older fixed jetway objects for new airport projects. It is therefore recommended that these be replaced as a matter of habit anytime you are working with an older airport submission too.
Be sure to check out the Adjustable Jetways manual for more information.
Connecting Jetways to Terminal Facades
Accurate placement of jetways is only part of the picture. Jetways look much more plausible when they join to a solid facade vertex.
Here are two examples to illustrate this point:
Not so good:
Here the jetways go straight into glass walls – not too likely in reality.
Here the jetways connect to solid portions of the terminal side – much more plausible !
Increasingly, modular construction is the way forward for the creation of airports that more closely resemble their real-life counterparts. Pre-constructed objects have fixed dimensions, often have unwanted features, and rarely resemble the real-life structure.
The addition of the Terminal Kit has opened up new opportunities, and despite some limitations, Gateway artists have been using this to inject modular constructions into their airports that have purposes other than terminal buildings.
Modular constructions have the added benefit of being laterally scaleable to the precise dimensions of the real-life structure – that is to say you may stretch them north-south, and east-west (using the WED marquee tool) until they precisely match the footprint of the real structure.
Consider the following two scenarios – the first constructed with conventional hangar objects from the X-Plane library, and the second with custom-built modules.
Default hangar objects:
The modular hangars perfectly match the ‘footprint’ of the real structures. Additionally, the artist had the option to construct open, partially-open, or closed doors here. A nice additional touch!
Pre-fabricated ‘LEGO-Brick’ Modules
Custom-built modules take time to construct. For this reason, we recommend checking out the following – where you are likely to find a module already built by another Gateway artist that closely meets your needs:
After importing your chosen module, you are of course free to re-size it, and make changes as needed !
Making perfect 90-degree angles (Orthagonalize function)
The ‘orthagonalize’ function (with short-cut CTRL+Q) is very useful for ensuring modules have perfect 90 degree angles, as illustrated here:
This prevents warped and irregular shapes when stretching, re-sizing and re-using modules later.
Perfect geometry (Make Regular Poly function)
The ‘Make Regular Poly(gon)’ function (with short-cut CTRL+SHIFT+Q) is very useful for ensuring modules are perfect circles, squares, rectangles, hexagons, etc – as illustrated here:
Matching Bezier Handles
The ‘Match Bezier Handles’ function (with short-cut CTRL+SHIFT+B) is essential to join polygons, where bezier handles are in effect, as illustrated here:
Note that, where the two polygons meet, the nodes must be snapped together before matching bezier handles.
Managing road-networks inside airport boundaries is crucial to a good outcome. Where possible, road-networks should be integrated into the design of your airport, but also excluded if they interfere with runways, taxiways and ramps, if segments of road-network are appearing in the wrong place, or if the road just looks implausible for some reason.
Incursions from Road Networks
Incursions that affect aircraft movements should of course be avoided – with the injection of one or more ‘Road Network’ exclusion zone(s).
Partial Incursions from Road Networks
Partial incursions are often apparent at airports. While these don’t affect aircraft operations directly (and often tolerated when the airport is moderated), these should be suppressed nonetheless. Traffic using the road will not disappear until it reaches the very end of the network.
Incursions ON Road Networks
Incursions by objects / structures / polygons ON road networks are common at airports. These are usually caused when the default road-network appears in a slightly different location to reality.
Gateway artists should avoid these incursions, either by offsetting the asset in question slightly (where a small change only is needed), or suppressing the road-network segment.
Isolated Road Network Segments
A common problem are isolated segments of road network – like this:
Use a carefully placed exclusion zone to suppress instances of isolated segments, while minimizing the loss of desirable portions of the network.
Cheating around Road Networks
Sometimes a small deviation from the real-life location of a structure, or feature at an airport allows for harmony with the X-Plane default road-network. This is because the X-Plane road network uses a vector-data algorithm to determine the location of the roads, and this is not so good at computing tight curves and complex intersections.
In the example below, the parking garages have been adjusted a few meters from their actual location, in order to co-exist with the road-network that bends around them. This is at the discretion of the artist, and should never compromise aircraft operations.
Avoid road duplication. When an airport features a manually constructed road, be sure to exclude all segments of the default road-network that may ‘compete’ with this.
Here is an example of what to avoid. The artist has gone to a lot of trouble creating the airport perimeter road, but has not excluded the default road-network, and so we have two roads overlaying one-another:
Parking lots often occupy huge areas of land in the vicinity of airports, and these have a great impact on the personality, and plausibility of your airport. Many otherwise excellent airport submissions on the Gateway have been compromised by their parking lots.
Until an improved parking lot facade is made available, construction of custom lots is far superior. This can be accomplished with manual placement of parking rows, above an asphalt polygon.
Default parking lot polygon (not recommended)
Custom parking lot (recommended)
Avoid placing individual lines or vehicles, and instead use…
‘14_Single_Spaces.agp’ and ‘7_Single_Spaces.agp’
to reduce the frame-rate impact of your custom parking lots:
If present in reality, hand-placed trees add a nice finishing touch to custom parking lots.
Forest Polygons vs Individual Trees
Forest polygons are excellent for ‘painting’ large areas of trees quickly and efficiently – both in terms of construction time, and rendering speed. However, do not bring forest polygons too close to areas of the airport that require precision. In these instances, individual hand-placed trees are required.
Taxi Route Networks
Don’t Connect Ramp Starts
There is no need to create taxi-route segments that connect the main taxiways to the ramp starts. Aircraft need to leave the taxi-network far from the ramp start, in order to make sensible parking maneuvers. Bringing the taxi-network close to the ramp start gives the aircraft no room to maneuver after exiting the network.
In the example below, the submission was originally declined because the artist had connected the taxi-routes all the way to the ramp starts. The artist’s solution was re-draw the network segments – NEARLY bringing them all the way to the ramp starts, but not quite. The airport now obeys the letter of the law and was ‘Approved’ on the Gateway. Unfortunately, this change did not solve the underlying problem – the AI still has very little room to maneuver:
This is better:
Ground Route Networks
The X-Plane ground truck AI works well for trucks traveling along the network, but less well for trucks joining and leaving the network. Artists are therefore encouraged to evaluate what lies between the parking location and the nearest network, and adjust the network, or truck-placement accordingly.
Consider the following examples:
In the above example, the truck will probably go directly through the terminal facade to join the network.
In this example, the truck will avoid the terminal building – until safely on the network.
Do not place trucks, or truck destinations on the network
Trucks, and truck destinations should be placed near to the network, but never on it. If a truck is located on a ground network, it may impede the flow of other trucks using the network.
Markings and Clutter
Markings and clutter bring airports to life. Even the best architectural work looks unfinished without these elements in your project:
Consider creating clutter groups in your WED project. Three groups of randomly chosen clutter objects is usually enough. You can use these groups repeatedly at various locations around the airport, with different orientations each time. It works well, saves a lot of time, and the duplication won’t be noticed!
In the above example, the same clutter group has been used three times, with a different orientation. The duplication is not easily noticed, and saves a great deal of time versus individual object placement.
Colored_area_green.pol and taxi-hatch
If your airport features green asphalt to indicate non-movement areas, be sure to use the Colored_area_Green polygon and not a draped sign polygon.
Custom Ramp Parking Areas
Ramp parking areas contain markings and other characteristics that differ between airports. The default ‘Ramp_Parking’ object often does not meet this need, and it is worth considering creating a custom design that can be replicated at each gate of your airport.
Here is an example in WED. The white markings have been custom made, and integrated with the default ramp stripe, a ramp start (with the appropriate size and type), and a grunge object that matches the desired footprint.
By creating a group in WED to contain the components of your custom ramp-start area, you can replicate the design quickly for every gate – by duplicating your group.
Here is what this particular design looks like in X-Plane:
Approach lighting piers
Approach lighting is normally a property of the runway itself (in WED). However, sometimes this does not yield the desired result – particularly if the lights at the real airport extend into the water on piers.
When relevant, custom lighting piers are a very nice touch that really enhances the approach to a runway. These can be constructed using:
You will need to disable the approach lighting associated with the runway in WED, and place individual lighting objects at the appropriate location on your pier facade instead.
Be sure to pick the correct lights and arrange these as they appear at the real airport. Enable ‘Set MSL’ for each lighting object, and use the appropriate altitude MSL to integrate these with your pier.
The wooden pier facade includes properties for pylons and railings. If these are enabled, take care to ensure these don’t obstruct the lights !
Here is an example custom-built approach lighting pier that demonstrates these techniques in action:
Static Aircraft vs Ramp Starts
Static aircraft objects will appear at the same location, and with the same appearance every time you visit the airport.
Aircraft spawned at ramp starts sometimes appear, and sometimes the ramp remains empty. This generates a degree of randomness that is plausible for a dynamic world.
As a general principle, you should use ramp starts at all locations where aircraft may potentially move, and static aircraft objects at all locations where you wish an aircraft to ALWAYS be present.
Testing your Airport (before submitting)
Submission volumes on the Gateway are generally very high, and the wait periods for moderation can be up to two weeks. To avoid frustrating delays, and possibly missing a vital cut-off date for the next X-Plane release, be sure to check out the document “Tips for Getting Your Airport Approved on the Gateway.”
Most frequent decline reasons
Look out for these!
- Runways, taxiways, ramps/ramp-starts, windsocks and airport-related objects and facades should be completely inside airport boundary.
- Segments of ATC network are joined to, or overlapping ramp starts.
- Taxiway/runway join issue(s). For info: https://forums.x-plane.org/index.php?/forums/topic/131437-how-to-draw-taxiway-exits/
- Ramp-start incursion(s) on nearby objects or facades.
- One or more ground truck parking locations/destinations is too far from nearest ground-route network.
- Airport has no ramp starts.
- (seaplane bases and closed airports are exceptions here)