Chapter 3: Initial Flight Setup

General Access
X-Plane has been written to operate on Windows, Macintosh, and Linux systems. For consistency’s sake, the layout and appearance of X-Plane is the same across all three. This may be slightly different than the interface that users are accustomed to, but once they pass the learning curve, they generally find it easy to use.

Here are a few pointers to help the learning process:
 * X-Plane's menu is hidden when the simulator is first launched. To access the menu bar, just move the mouse pointer to the top of the screen.  When the mouse is within a centimeter or so of the top edge of the screen, the menu bar will appear.  There is no keyboard command to access the menu bar.
 * Any window within X-Plane can be closed by clicking either of the Xs found in the upper left and upper right corners. Alternatively, those windows may be closed by hitting the Enter/Return key.
 * Key commands can be found by opening the Joystick & Equipment screen and going to the Keys tab. Key command assignments can also be changed using this screen (see Chapter 4) to anything desired.  Also, note that many of the keyboard shortcuts are shown in the X-Plane menus.  For example, opening the View menu will display the list of available views on the left side of the drop down menu, with the list of corresponding keyboard shortcuts on the right.

Like most programs, the simplest way to navigate around X-Plane is using the mouse, though there are many shortcut key commands to help a user navigate quickly through the options after he or she becomes more familiar with the program. These shortcuts are particularly important when using the mouse to fly. In that case, it is much easier to use the '2' key to drop a notch of flaps than it is to let go of the controls, reach down with the mouse to adjust the flaps, and then reach back up and grab the controls again.

Also note that most instruments and controls inside the cockpit are interactive, meaning that the mouse can be used to alter switches, set frequencies, manipulate the throttle(s), change the trim, etc.

Before using X-Plane, the user may need to configure and calibrate the joystick (if applicable) and set the display options to optimize the software for use with the system.

Joystick Configuration and Calibration
Note: When using a joystick or other hardware, it will need to be plugged in before starting X-Plane. If it is not, X-Plane will not see the input devices.

The first thing that must be done to use a joystick (or other input device) with X-Plane is to properly configure it within the program. Throughout this section we will refer to any input device as a joystick; the instructions apply to yokes, throttle quadrants, and rudders also.

Axis Assignment
Once X-Plane is running, move the mouse to the top of the screen and click Settings, then select Joystick & Equipment, as in the following screenshot.


 * [[Image:Settings--Joystick_and_Equip.png]]

This will bring up the window allowing the user to configure and calibrate the flight controls. If it isn’t already selected, click on the Axis tab at the top of the screen.

To begin, move the joystick’s controls around to see how the axes are mapped in X-Plane. As this is done, one of the green or red bars will move for each input that is actuated. Thus, when the stick is rolled left and right only one green or red bar will move; when it is pushed back and forth another bar will move. Each control’s desired function is selected from the drop down box to the left of its bar.


 * [[Image:Calibrate_axes.png]]

The axis bars are green when they are assigned a function, and they are red when they are not assigned a function. For instance, before the throttle axis has been configured, moving the throttle might move a red bar. After assigning that bar to throttle, it will turn green.

The normal configuration is as follows:


 * 1. Move your joystick or yoke forward and back. A green or red bar should move as you do so.  Click the drop-down menu next to it and set it to pitch.  Do not check the reverse box next to this control unless, when flying, the aircraft’s pitch control is working backward.


 * 2. Move your joystick/yoke left and right. The green or red bar that moves should be set to roll.  Do not check the reverse box next to this control unless, when flying, the aircraft’s roll control is working backward.


 * 3. Twist your joystick (if applicable). The bar that moves should be set to yaw.  If you do not assign a yaw axis, X-Plane will attempt to stabilize it for you.  Once again, do not check the reverse box unless, when flying, the aircraft’s yaw control is working backward.


 * If using rudder pedals, slide them forward and backward and set the green/red bar that moves then to yaw.


 * Additionally, only when using rudder pedals, press the left pedal down with your toes. The green or red bar that moves should be set to left toe brake.  Do the same for the right pedal, and set that green bar to right toe brake.


 * 4. Move your throttle forward and back (on a yoke, this is typically the leftmost lever). Set this bar to throttle.

Note: Any green bar which is not actively controlled by your hardware needs to be set to none. When this is set, the bar will turn red, indicating that X-Plane is not using the axis.

Control Calibration
Control calibration is a step of vital importance that often gets left out. It is, however, necessary due to the vast array of hardware that X-Plane can interface with. Some devices may send a signal from 0 to 1,000 when a user moves a given control from one limit to the opposite, while another device may send a signal (given the same movement of a user’s hand or foot) from, say, -6,000 to 3,992. The only way for X-Plane to know the range of the joystick’s input is for the user to “teach” it.

All it takes to calibrate the joystick hardware is to move all the axes of the joystick through their full range of motion while on the Axis tab of the Joystick & Equipment window. Be sure to move each of the joystick’s variable controls (that is, all sliders, joysticks, rudders, etc.) through their full range of motion—-take them all the way forward, all the way back, left, and right. All of this can be done quite rapidly, as X-Plane can monitor all the different inputs at once.

Button Assignment
Each of the buttons and switches on the joystick can be assigned a function within X-Plane (for example, toggling the brakes or landing gear). To do this, open the Buttons: Basic tab of the Joystick & Equipment window (outdated versions of X-Plane have only a Buttons tab). As you operate your joystick’s buttons and switches you will see the box in the upper left corner change the number it displays. This indicates that X-Plane has received the input and is ready to assign that button/switch a function.

The instructions below reference only buttons. They apply, however, to switches too, though a switch can have a function assigned to both its “up” and “down.”

To change a button assignment, simply operate that button on your joystick and then select the function that should be assigned to it by clicking on the circular toggle next to it. Repeat this operation for as many buttons as need functions assigned. Close the Joystick & Equipment window and the settings will be saved.

For instance, in the following screenshot, a button was pressed on the joystick—-it happened to be button 000. The round button next to Toggle brakes regular effort was clicked, thus setting button 000 to toggle the brakes.


 * [[Image:Toggle_brakes.png]]

Note: Users must select the desired button by pressing and releasing it prior to assigning it a function. If this is not done, the assignment of the last button pressed will be overwritten.

Sensitivity
To modify the joystick’s sensitivity or the stability of the aircraft, open the Center tab at the top of the Joystick & Equipment screen. The top-left sliders (seen below) control the response curves for the pitch, roll, and yaw axes of the joystick.


 * [[Image:Joystick_and_Equip_-_Sensitivity.png]]

If these sliders are set all the way to the left, the aircraft’s response to that axis’ input will be completely linear. This means that a 50% deflection of the joystick will deflect the airplane’s flight controls 50% of their travel. As these sliders are moved to the right the response becomes curved. In this case, a deflection of the joystick from center to its halfway point may only deflect the aircraft's controls by 10%. This will dampen any aircraft movements and desensitize the user’s controls. Keep in mind, however, that in this case, the remaining 90% of the control surface deflection must take place in the last 50% of joystick movement. Thus, the controls will be dampened for the first half or so of their travel and then become hyper-sensitive for the remainder of their throw. This gives the user plenty of fine-tune control near the center of the flight control envelope to hold altitude and roll precisely, but still allows for full control authority at the extremes.

Try flying with the sliders in various different positions to see what setting works best.

Stability
In the upper right portion of the Center tab’s screen is another set of sliders, seen in the following image.


 * [[Image:Joystick_and_equip_-_stability.png]]

These control X-Plane’s stability augmentation mode by dampening the predicted forces acting on the aircraft flight control surfaces. If these sliders are all the way to the left, then there is no stability augmentation of the aircraft. As the sliders are moved to the right, X-Plane will automatically add some stability augmentation to the aircraft, adding some elevator input to level the nose, some aileron input to minimize the roll rate, and some rudder input to counter any aircraft yaw rates. In other words, the simulator will try to make the plane easier to fly by adding control inputs for the user. The downside, of course, is that as X-Plane adds stability, the aircraft becomes less responsive (and less realistic).

Setting Null Zones
Null zones determine how much the joystick must be moved before X-Plane actually starts to take action. A null zone may be set for each joystick axis to fine-tune how responsive the control surface inputs are, but this function is typically used to prevent hardware from 'creeping' in flight or to ignore the constant 'jittering' that many older controllers will send to X-Plane.

To set a null zone, first open the Center tab of the Joystick & Equipment window. Now drag the nullzone slider (on the lower half of the window, seen in the following image) to the desired position; the greater the percentage, the higher the “dead range” that will not affect the airplane’s controls.


 * [[Image:Joystick_and_equp_-_center_-_null_zones_center.png]]

Close the dialog and these axis positions will be saved.

Centering the Controls
Directly beneath the nullzone slider (seen in the image above) is the CENTER YOKE AND PEDALS button. Using this button will allow the user to correct for flight controls that don’t return to the center of their range-—for instance, a joystick that moves left to right in a range of 0 to 100, but returns to 55 when the user lets go of it. Without centering such a joystick, the craft would constantly roll to the right.

Adding Special Equipment
The final tab in the Joystick & Equipment window, Equipment, is used to setup special equipment for use in X-Plane. This tab is generally used on multi-computer X-Plane configurations in professional, FAA-certified simulators or to tie in various GPS navigators (such as a real Garmin 96/296/396 or a 430 GPS radio). After being connected to the computer, this equipment should be set up per the manufacturer’s recommendations, then checked off on the Equipment screen to tell X-Plane that it is connected.

Troubleshooting Flight Controls
If the joystick and other flight controls appear to be configured correctly according to the above sections but are not giving the desired response in the simulator, it’s time to troubleshoot. Thankfully, X-Plane makes it easy to find out how the software is perceiving the flight controls’ input.

In the following example we’ll assume that the plane’s pitch, yaw, and roll are not matching the way the joystick is being moved. A similar procedure may be used for other malfunctioning controls.


 * 1. Move your mouse to the top of the screen and open the Settings menu.


 * 2. Click Data Input & Output, as seen below.


 * [[Image:Data_in_and_out_-_selecting_it.png]]


 * 3. Select the rightmost box next to joystick 1 ail/elv/rud (found in the fourth group from the top in the far left column, as seen in the following screenshot). This box will cause X-Plane to display the input it is receiving while running the simulation.


 * [[Image:Turn_on_joystick_ail_elv_rud_crop.png]]


 * 4. Close the Data Input & Output window.


 * 5. A box in the upper right should be displaying the elev, ailrn, and ruddr commands (elevator, aileron, rudder) being received from the joystick.


 * For instance, in the following screenshot, the stick is being pulled back and to the left with a neutral yaw axis (thus deflecting both the elev and ailrn inputs from zero, but leaving the ruddr at about zero).


 * [[Image:Result_of_ail_elv_rud_crop.png]]


 * 6. Now, center the stick and pedals. Each axis should indicate 0.0000, or close to it.


 * 7. Move the stick full left. The ailrn should indicate -1.0000 or near -1.0000.


 * 8. Move the stick full right. The ailrn should indicate 1.0000 or near 1.0000.


 * 9. Move the stick full aft. The elev should indicate 1.0000 or near 1.0000.


 * 10. Move the stick full forward. The elev should indicate -1.0000 or near -1.0000.


 * 11. Move the rudder full left. The ruddr should indicate -1.0000 or near -1.0000.


 * 12. Move the rudder full right. The ruddr should indicate 1.0000 or near 1.0000.

By moving the stick and pedals and seeing what values they are sending X-Plane, the user can see if X-Plane is getting proper stick input.

If the correct values (according to the tests above) are not being received in X-Plane, then the issue is with the hardware’s calibration in Windows (not X-Plane). If it is indeed calibrated correctly in Windows, the hardware itself is malfunctioning. On the other hand, if the correct values from the above tests are being received, then the hardware is working fine.

Rendering Options Setup
X-Plane is a very advanced simulator that has been designed for use across a broad range of computers with varying specifications. As such, X-Plane provides the user with the option to make changes to numerous settings to optimize performance with a particular system set up. For this reason, this is one of the most critical portions of this manual. The Rendering Options window allows users to match X-Plane's settings (and thus the demands the simulator puts on the computer) to their computers’ capabilities. The Rendering Options screen is where all the settings affecting the display quality and X-Plane's performance are set. The settings in this window will likely need to be experimented with to get the best results from X-Plane on a specific computer. Generally speaking, the higher the rendering options are set, the lower the performance and frame rate achieved. The rendering options that are set will have a greater effect on X-Plane’s performance than any other changes that users can make.

The Rendering Options screen can be found by moving the mouse to the top of the screen, opening the Settings menu, and clicking Rendering Options, as in the following screenshot.


 * [[Image:Selecting_Rendering_Options.png]]

Frame Rate and the Quality of Flight Simulation
Here is why frame rate is so important to the realism of X-Plane’s simulation.

The simulator's performance is measured in frames per second (FPS). This number is referred to as frame rate. This is how many times per second the complete set of programming (currently more than 700,000 lines of code!) can be run. Each time the computer runs through the program it advances the aircraft and recalculates the images that are seen (cloud formations, scenery, aircraft instruments, other aircraft, etc.).

Obviously, X-Plane has to be tremendously flexible to be able to run on a three year old computer and also take full advantage of the latest and greatest hardware available. There are two things that affect X-Plane’s frame rate-—first, the computer's capabilities and second, how much it is being asked to simulate (e.g., how much visibility is set, how many buildings, clouds, and other aircraft are being drawn, etc.). It will be much harder for the computer to compute images when flying an airplane in thirty mile visibility with 8,000 three-dimensional buildings and cloud puffs than it would be if X-Plane were set up with only two or three miles of visibility and no clouds.

The faster a computer can run X-Plane the more realistic and rewarding the simulation will be. Testing has shown that the human brain can separate individual frames at frame rates of less than about 20 FPS, causing the simulation to appear “choppy.” Coincidentally, this is also about the same place that the engineering behind the simulation begins to fall apart. For this reason, X-Plane has set the minimum operating speed at this level. If a computer is not capable of delivering a frame rate of 20 FPS while rendering the level of detail set up in the Rendering Options page, X-Plane will automatically introduce fog to help the simulation to run more smoothly. The fog keeps X-Plane from having to draw the world to as great a distance, allowing the simulation to run faster.

Setting Up the Monitor
The following options (Texture Resolution, Screen Res, Anti-Alias Level, etc.) are all found on the Rendering Options Screen, accessed by moving the mouse to the top of the screen (thus making the menu appear), clicking Settings, then Rendering Options, as seen below.


 * [[Image:Selecting_Rendering_Options.png]]

Texture Resolution
The Texture Resolution drop-down box (highlighted in the image below) determines the clarity and detail of the textures displayed in X-Plane.


 * [[Image:Texture_res.png]]

Textures are the image-maps that are draped over the terrain and aircraft to make them look realistic. If the texture resolution is set to low, the runway and terrain will look rather blurry and blocky. While this will not look very good, it will use very little video memory (VRAM), so a high frame rate will be more easily achievable. The more powerful a computer’s video card is, though, the higher the texture resolution can be set in X-Plane without hurting the frame rate. The frame rate will be very badly reduced, though, if a texture resolution is selected that requires more VRAM than the computer’s video card has.

Users can easily determine how much VRAM is required to render the given level of detail-—the very bottom of the Rendering Options screen reads “Total size of all loaded textures at current settings: xx.xx meg.” For instance, in the image below, X-Plane has loaded 75.44 MB of textures into VRAM.


 * [[Image:Total_size_of_all_loaded_textures.png]]

In most cases, this number will only be updated after X-Plane is restarted—-that is, users cannot change the texture resolution, close the Rendering Options window, and reopen it to check the amount of VRAM used.

If the system has a 128 MB video card and the VRAM currently used is only 32 MB, then a higher texture resolution can be set without problems. This will cause the scenery, runway, and airplane to all look sharper and crisper. As long as X-Plane is not requiring more VRAM than the system’s video card has, the simulation’s frame rate will not be impacted. Note that if a texture resolution is set which requires substantially more VRAM than the video card has, the sim’s frame rate will be massively impacted as the computer begins to use system RAM to store textures—-a very slow process.

In a perfect world, the VRAM used will be about equal to or a bit more than the VRAM of the system’s video card. This will give maximum texture detail without overflowing the video card’s memory and reducing the frame rate.

Set Color Depth and Monitor Resolution on X-Plane Startup
If the set color depth and monitor resolution on X-Plane startup box (highlighted in the screenshot below) is checked, X-Plane will automatically reset the computer’s monitor to the resolution that X-Plane is set to every time the program loads.


 * [[Image:Set_color_depth.png]]

This forces the sim to always run full-screen. Note that this does not set X-Plane to the current resolution in Windows; to do that, read down to Screen Res (Resolution).

If this box is checked, the user will also get to choose a color depth of 16-bit or 32-bit. 32-bit looks a little better. If this box is not checked, then X-Plane will run in whatever the color depth is set to in the operating system, which is probably 32-bit (or "millions of colors" as described on Macs).

Note: If the system’s monitor does not have a 4:3 aspect ratio, everything on the screen will be distorted if X-Plane is forced to run in full screen (by checking the set color depth and monitor resolution on X-Plane startup button) with a screen resolution of 1024x768. This is caused by X-Plane trying to stretch a 4:3 image into a 16:9 or 16:10 space. For a detailed discussion on these aspect ratios, please see the discussion in Chapter 2.

Anti-Alias Level
The anti-alias option, highlighted in the following image is pretty interesting.


 * [[Image:Anti-aliasing.png]]

There are only about a million pixels on a computer’s monitor. This may seem like a lot, but in reality, it's not for what X-Plane is doing. When a computer tries to draw diagonal lines across the rectangular pixels of a monitor, "jaggies" result—pixelated-looking "stair-stepped" lines. These jaggies may be (somewhat) eliminated by selecting anti-aliasing. This will cause X-Plane to actually draw the simulated world several times per frame and blend those frames together, resulting in a better looking image. This will completely kill the sim’s frame rate if the system doesn’t have a strong video card, but if the video card can take it, crank this option up.

Screen Res (Resolution)
This control (highlighted in the image below) sets the screen resolution of the X-Plane window.


 * [[Image:Screen_res.png]]

To change the resolution, click the up or down arrow next to each digit of the setting. For example, to change the resolution from 1024 x 768 in the image above to, say, 1280 x 768, one would click twice on the arrow above the zero in 1024, six times on the arrow above the two in 1024, and four times on the arrow below the four in 1024.

The default and recommended resolution setting is 1024 x 768 pixels. Other screen resolutions can be used, but the simulation’s frame rate will deteriorate a little as the screen area increases.

Making X-Plane Full Screen
The screen res control can also be used to cause X-Plane to fill the entire screen. If the X-Plane window does not fill the screen, determine what screen resolution the computer is running at and enter that resolution here. This can also be done the other way around, by setting the resolution of the computer to match the resolution in X-Plane. Changes to this setting will take effect after X-Plane is restarted.

Windows XP users can determine their current resolution (and change it) by doing the following:


 * 1. Right click on the Desktop and click Properties.


 * 2. In the window that opens, click the Settings tab.


 * 3. Drag the Screen Resolution slider to the desired resolution.

In Vista:


 * 1. Right click on the Desktop and choose Personalize.


 * 2. Click Display Settings.


 * 3. Drag the resolution slider to the desired resolution.

In Windows 7:


 * 1. Right click on the Desktop and click Screen Resolution.


 * 2. Click on the Resolution drop-down box and drag the slider to the desired resolution.

Mac users can do the same by doing the following:


 * 1. Open the System Preferences from either the dock or the Apple menu.


 * 2. Open the Displays menu and click on the Display tab.


 * 3. Select the desired resolution under “Resolutions.”

Changing X-Plane's resolution to match the resolution of a widescreen monitor will cause most 2-D cockpits to have blank bars on their left and right, through which scenery outside the plane will be visible. Common widescreen resolutions are 1920 x 1080, 1440 x 900, 1360 x 768, 1280 x 720, etc. For more information on this problem, see Chapter 2.

Draw IOS on Second Monitor on Same Video Card
An Instructor’s Operating Station (IOS) may be run from the same computer as the sim when using a dual output video card. To enable this, check the box next to draw IOS on second monitor, highlighted below.


 * [[Image:Draw_ios.png]]

The video card must first be configured to output to both screens in the operating system. Checking this box will cause a second X-Plane window to open on the second screen. In this window, move the mouse to the top of the screen and click Location, then Local Map. There, check the IOS box, as shown in the following image.


 * [[Image:Local_map_-_checking_ios.png]]

On the left will appear the options to load different aircraft, relocate the aircraft, fail systems, and alter the weather for the “student” pilot. Note that this IOS functionality is available not only on a second screen on the same computer, but also from a second computer networked to the student computer via a LAN or the Internet. This option has no effect on frame rate.

For more information on running an IOS, see Chapter 5.

Setting Up the X-Plane World
Each of the controls in this part of the chapter (Setting Up the X-Plane World) is found in the PERFORMANCE RENDERING OPTIONS section of the Rendering Options window, highlighted in the following image.


 * [[Image:Performance_rendering_options.png]]

Forest Density
This control determines how dense the forest and shrubbery are in X-Plane. Keep in mind that drawing more and more dense forestry will have a moderate effect on the simulator's ability to maintain frame rate.

World Detail Distance
This will set the level of detail for objects in the world scenery, and from how far away this detail will be visible. Changes to this setting will take effect after X-Plane is restarted and have a large effect on frame rate. Be careful with this one.

Number of Objects
This will determine how many three-dimensional objects (e.g., buildings) are drawn in the world scenery. This will have a very strong effect on the simulator's performance-—flying over New York City with 8,000 little 3D buildings is much more difficult for X-Plane to draw than flying over rural Iowa with only 20. Changes to this setting will take effect after X-Plane is restarted.

Number of Roads
This will set the number and complexity of roads and rivers being displayed in X-Plane. Changes to this setting will take effect after X-Plane is restarted and have a moderate to large effect on frame rate.

Airport Detail
This drop-down menu modifies the level of detail rendered at airports, adding windsocks, beacon lights, and texture and markers to runways. It has a minimal effect on frame rate.

Traffic Density
This control modifies the amount of air traffic, as well as the amount of the associated ATC communications heard over the radio. It has a minimal effect on frame rate.

Anisotropic Filter Textures
Anisotropic filtering is a somewhat complicated concept.

Imagine taking a photograph and looking at it from about two feet away, with your eyes directly above the image and perpendicular to it. Things are clear and sharp, right? Now imagine taking the same picture and rotating it 90 degrees away from you so you're looking at the edge. Obviously, the image is no longer visible. Now rotate it back towards you 5 or 10 degrees. You can just start to make out the image, but since you're looking at it from such a low angle, the picture is fuzzy and poorly defined.

This is analogous to looking at the X-Plane scenery from a low altitude on a clear day. The images directly in front of the aircraft will be relatively clear, but the closer the scenery gets to the horizon, the fuzzier the image becomes. The anisotropic filter helps to clear this fuzziness away, making the image clearer. This option has a minimal effect on most machines and a moderate impact on some machines. Try it out and see if you like it and if you can live with the performance penalty.

Draw Birds in Nice Weather
This is a relatively new feature in X-Plane that arose from a near-miss between Austin (the author of X-Plane) and a small flock of birds. He was departing from Columbia, South Carolina one day in his Cirrus. As he was climbing out, a flock of birds flew in front of his aircraft and Austin thought he was about to incur multiple collisions. As it turned out, the birds did not collide with him, but it was enough to open his eyes to realize that this potential hazard needed to be modeled in X-Plane.

Each bird in X-Plane is modeled independently and has its own “mission.” For this reason, the flocks of birds look very realistic. Colliding with the birds will cause damage to the aircraft as well as engine failures and other things, just like in reality. This control has a marginal effect on frame rate.

Draw Hi-Res Planet Textures from Orbit
X-Plane can simulate orbital and sub-orbital flight using the Space Shuttle and other spacecraft. If selected, this option will display high-resolution images of the Earth when simulating space flights. These high-resolution images will typically be displayed at altitudes of 100,000 feet or higher. This has no effect on frame rate except when flying above that altitude.

Draw Forest Fires and Balloons in Warm Weather
When checked, this option will draw randomly generated forest fires for practicing water bombing. X-Plane can realistically simulate such operations, requiring the user to fly a water bomber such as the CL-415 (found in the Seaplanes folder) and scoop up water from the ocean or a nearby lake. This option has a negligible effect on frame rate.

Draw View Indicator
This is a handy feature that will draw a little orange triangle in the top center of the screen when looking any direction other than forwards. It rotates about a depiction of the aircraft and points in the direction that the screen is viewing. This is helpful in maintaining situational awareness. This option has a negligible effect on frame rate.

Dim Under High G Load or Hypoxia
When this box is checked, X-Plane will simulate the effects of gravity, creating G-force blackouts under tight maneuvers or hypoxia from high altitude flying. These effects are true to life, causing the screen to either “black out” or “red out,” just as a pilot would experience a loss of vision under extreme high or low G situations. Additionally, a black out will occur when flying at too high an altitude without first setting the pressurization or oxygen system, just like in real life. This option has a negligible effect on frame rate.

Use Pixel Shaders for Amazing Fog and Water Effects
Using pixel shaders allows X-Plane to add 3D lighting on a per-pixel basis. Rather than having the simulator tell the graphics card how to light an area, the graphics card determines it in real time, creating a very realistic image. Depending on the graphics card, this can have a large effect on frame rate.

Draw Volumetric Fog
This option only appears when using pixel shaders. Normally, fog is applied to the entire scene with the same density. Using volumetric fog creates a number of small, localized fog effects, causing the density to vary. This can have a significant effect on frame rate.

Water Reflection Level
This option also appears only when using pixel shaders. Changing the reflection level of the water also changes how many calculations the computer must do on each pixel in the water. Its effect on frame rate varies based on the amount of water in the scene.

Expert Rendering Options
The following three controls are found in the EXPERT RENDERING OPTIONS section (highlighted in the following image) of the Rendering options screen.


 * [[Image:Expert_rendering_opts.png]]

Compress Textures to Save VRAM
Checking this box and restarting X-Plane may enable the simulator to use about twice the VRAM as before without overflowing the video card. However, doing so may cause some of the crispness and precision to be lost from textures. Try it out and see what happens.

Do Any Scenery Loads in the Background
This causes X-Plane to try to load as much scenery as possible without pausing. This is where a dual- or quad-core processor really shines.

Runways Follow Terrain Contours
X-Plane includes a feature whereby runways and taxiways can follow the elevations of the terrain upon which they are drawn. In some cases, the changes in elevation of the terrain may be very abrupt, which can make airport runways overly bumpy. Unchecking this box will cause X-Plane to flatten the terrain under runways to alleviate potential problems. This option has no effect on frame rate.

Special Viewing Controls
The following controls are found in the SPECIAL VIEWING CONTROLS section (shown in the screenshot below) of the Rendering Options window.


 * [[Image:Special_viewing_controls.png]]

Lateral Field of View
The field of view setting will change the way X-Plane displays the view of the outside world. Higher settings will allow more of the terrain to be viewed at any one time, but will reduce performance. Higher settings will also increase the “fish eye” effect of the simulator. The default value is 45 degrees, which generally gives good performance and a natural view.

Minimum Frame Rate
As discussed earlier in this chapter, the frame rate is the number of unique pictures (“frames”) that the simulator displays per second. The term comes from the motion picture industry, where each frame was a separate picture taken by a movie camera. In X-Plane, as frame rate increases, so does the accuracy of the flight model and its visual appeal. This control will set a minimum frame rate that X-Plane will attempt to maintain. If the system has too many rendering options set too high, X-Plane will automatically reduce the visibility in an attempt to maintain the frame rate specified here.

The frame rate should not go below 20 frames per second (fps) because the flight model needs at least 20 fps to do a decent job simulating most airplanes. On smaller, lighter planes, though, which have less inertia and more speed and maneuverability, X-Plane will need more than 20 fps to fly accurately. This is due to these planes’ ability to flicker around the sky so quickly. A high frame rate is needed to accurately track the plane's rapid accelerations.

If the frame rate gets too low for the flight model to handle, then the plane is likely to start oscillating quickly back and forth (referred to as “simulator flutter,” often occurring with autopilot on) as the flight model tries unsuccessfully to predict what the plane will do next. At this point, the computer is running too slowly to take small enough steps in the flight model to see what the plane will really do at each moment. Smaller and more maneuverable planes will accelerate more quickly, and greater accelerations require a higher frame rate to simulate.

Multi-Computer Simulators
The following options in the Special Viewing Controls are used for multi-monitor or multi-computer simulators. A setup like this allows X-Plane to run different views on different monitors (for example, a left, center, and right view on three different monitors, or an instrument panel on one screen and the forward view on a second screen). Note that in a multi-computer setup, each computer requires its own copy of X-Plane.

To set up a multi-computer simulator, the various computers must first be linked together over a network. X-Plane should then be launched on each computer. On each computer, open the Settings menu and click Data Input & Output. On this screen go to the Inet 1 or Inet 2 tab and enter the various IP addresses of the different machines in the appropriate location.

For more information on multi-computer setups, see Chapter 6's Net Connections section, as well as Chapter 8's  Setting Up Advanced Networks and  Setting Up Multiple Monitors. Don't hesitate to call customer service if you have difficulty and would like some assistance.

Under normal, single computer configurations, these options can all be left at their default values

Lateral, Vertical, and Roll Offsets
Let's say that you have three networked computers for additional visuals to form a wrap-around cockpit. Each computer might have a 40 degree FOV. You should enter a lateral offset of -40 degrees for the left visual, 0 for the front visual, and +40 degrees for the right visual. If each visual has a field of view of 40 degrees, these images will blend together seamlessly if you don't consider the width of the frame around the monitor. If you cannot set up the monitors to run their effective image all the way to the edge (as you can with some, even though you won’t be able to see the part theoretically under the border) then you might try a field of view of maybe 38 degrees, based on whatever fraction of the monitor is visible.

Vertical and roll offsets are the up/down and tilt equivalents of the lateral offset.

Please note that lateral, vertical, and roll offsets are only available in degrees; ratio values are no longer supported.

Note: While the view offsets do indicate how much to the left or right or up or down each view is looking, people still make the same mistake over and over: they run a center view with a cockpit in the center screen, and external visuals on the left and right (which is fine) but they notice that the horizon in the center (cockpit) screen does not line up with the horizons on either side. The reason for this is that the center-point of the screen where the horizon rests in a level flight attitude is up near the top of the screen in the cockpit view (to make room for the instrument panel) and the center of the screen for the external visuals (which do not need room at the bottom for the instrument panel). Often, people will incorrectly lower the vertical offset of the center panel (with the cockpit).

This results in countless problems with the views not lining up. It is like taking the wheels off the left side of one’s car and then thinking the problem is solved by holding the steering wheel to the right to drive straight. It is not the correct response to the problem. In this case, users should go to the viewpoint screen in Plane-Maker and set the cockpit viewpoint center to 384 pixels (that is, half of the 768 pixel height of the screen) so that the viewpoint center in the cockpit window is the same as the viewpoint center in the side-view screens. Only then will the horizon always line up across all the visuals! In other words, the only time a vertical offset should be used is if there is one monitor on top of another. If a user has to enter a vertical offset for one of two monitors that sit beside each other, s/he is doing something wrong! The problem should be solved by making sure that the viewpoint center is at the same pixel height on all the computer monitors that are side-by-side, and that height is always 384 pixels (halfway up a 768 pixel screen) for the external visuals.

Lock View to Forward Cockpit
When views are changed within X-Plane, that changed view propagates to all the external visuals. Checking this box causes a view to always be forward-with-cockpit.

Setting up X-Plane to Achieve the Best Results
Please see Setting Up X-Plane for Best Performance for instructions on optimizing X-Plane’s performance for the best performance on a given computer.