Ground2K for Beginners

 

An Introduction to Ground2K version 4

 

July 2003

 

 

 

 

Index

 

Description of Ground2K

An explanation of Flight Simulator terrain

Using Ground2K

Installation of scenery

Common problems and errors

Glossary

Support

 

 

 

 

 

These short user notes for Ground2K by Christian Fumey are meant for the beginner who would like to modify the default terrain scenery in Microsoft Flight Simulator 2002, but has no knowledge of the concepts or tools available.

These notes are NOT a replacement for Christian’s notes accompanying his program. Instead, they should be considered a supplement providing basic knowledge for beginners.

Please take the time to read Christian’s notes – they are far more comprehensive than what you will find here, and cover the functions of Ground2K in much greater detail.

In order to avoid any confusion caused by unfamiliar jargon, you will not find technical terms or explanations of the inner workings of Flight Simulator terrain here.

If you desire to learn more about this, you should consult the TMF Manual (tmf_manual.zip available in the AvSim library) by Christian Stock, pioneer in the field – this is a relatively easy to understand and very complete explanation on the subject. Essential reading for everyone who makes or modifies terrain.

For a more specialized and highly technical explanation of these matters, please read the LWM Tutorial (lwmtut.zip available in the AvSim library) by Richard Ludowise. Thanks to Dick’s knowledge of the Flight Simulator terrain engine and his wonderful tools, it has been possible to create easy to use programs like Ground2K.

If you wish to know the official party line on the subject, you can download the numerous Microsoft Software Development Kits (S.D.K.), available on the Microsoft Flight Simulator 2002 web site ( http://zone.msn.com/flightsim/default.asp ).

 

What does it do?

Ground2K is a very easy-to-use drawing tool for Microsoft Flight Simulator 2002 with which you can:

-         exclude elements of the default terrain;

-         create roads and railroads;

-         create coasts and shorelines;

-         create rivers or streams;

-         create lakes and other bodies of water;

-         create islands, either within a lake or on the open sea;

-         change the default land classification assignments;

-         change the default water classification assignments;

-         inlay textured polygons directly into the ground using textures of your choice (as, for example, parks, gardens, high-detail aerial images, etc);

-         modify the terrain attributes of  entire regions;

-    modify the altitude mesh;

-         and even draw your shapes by simply flying or slewing over the terrain within Flight Simulator.

 

There are some things that you CANNOT do with Ground2K:

-         you CANNOT  import Land Cover/Land Use data and have Ground2K automatically create the appropriate Flight Simulator land class;

-         you CANNOT import SHAPE files and have Ground2K automatically create roads, rivers, coasts, lakes, etc.;

-         you CANNOT import a background image (map or aerial picture) and have Ground2K automatically determine the terrain elements;

-         you CANNOT create large-scale custom terrain (photo-real ground textures) using aerial images.

 

Ground2K is a drawing tool – this means that you must draw all the terrain elements yourself. However, the process is extremely simple and the program automates all the difficult or complex parts. For example, you are not required to break down your drawings into simple convex shapes – you can make lines as complex as you wish. Or, your lines do not need to be cut off at the boundaries of the ground tile – you can extend all lines as far as is necessary.

At the moment, all the details of Flight Simulator terrain are not yet known. This means that you may occasionally get unexpected results or even crash Flight Simulator with your new scenery. This should only happen, however, if you attempt something out of the ordinary. For most users, this will not occur.

In any case, it is simple to just throw out the offending scenery and try again. The process is quick and simple and you are encouraged to experiment and discover all the possibilities yourself.

 

Theory and Practice

In this short user’s guide, you will essentially find 2 sections.

The first clarifies some basic concepts that should help you better understand the terrain scenery in Flight Simulator 2002. These explanations deal with the following:

1.      the new type of terrain and its structure;

2.      the use of layers;

3.      the LOD grid;

4.      land and water class.

The second section is the user guide itself, and presents a concrete example of scenery creation where you can learn some of the principal functions of Ground2K. Here, you will find how:

1.      to create a background bitmap over which you can draw new terrain elements;

2.      to exclude the default terrain elements;

3.      to create new coasts and shorelines;

4.      to create roads and railroads;

5.      to create lakes;

6.      to create textured polygons;

7.      to modify the land and water class;

8.    to modify the altitude mesh.

  In addition, there is a short section on installing your new scenery and how to get answers to your questions and solutions for your problems.

If you prefer, you do not have to read the first part, but can simply jump right to the second part and start making scenery. “Learn by doing” is a perfectly valid way to gain the necessary knowledge.

 

The Way of the World

The new world order

The latest version of Flight Simulator has introduced some very important changes in the way that terrain scenery is displayed.

In Flight Simulator 2000, terrain consisted of an altitude mesh underlying a number of layers of textured polygons. For example, there was a layer of ground textures upon which was placed a layer of water textures. On top of this came a layer of airport ground and then, many times, another layer with textures representing parks or golf courses. Finally, a layer of roads. All these layers created a tremendous strain on the resources of the graphics card, as it struggled to paint them all. The result was very low frame rates and the infamous “stuttering” as the graphics card stopped drawing while it loaded all the textures into its memory. There was also a lot of “shimmering” due to the conflict between the different layers of textures – often, the graphics engine could not decide which layer should appear on top.

The new version of Flight Simulator has taken a completely different approach to terrain scenery. There is still an underlying altitude mesh, but the various layers of textures have been eliminated. Instead, the ground now consists of different elements that are combined by the graphics engine into one unique ground tile. The assigned land class calls a particular ground texture onto which are integrated various terrain elements. These elements – coastline data, river and lake data, road and railroad data, special ground textures for airport skirtings and parks – are directly inlaid into the ground tile before being drawn by the graphics engine.

Here is an example, taken from the TMF Manual, by Christian Stock:

 

 

 

You can see that the graphics engine takes the ground texture, a water texture, and a line depicting a lake, then creates a single unique ground tile integrating all these elements

The result is that the graphics card must now draw only one texture, and not multiple layers of textures. Frame rates have gone up and stuttering has been mostly eliminated.

This is without a doubt the single greatest advance of Flight Simulator 2002 and an admirable achievement by the Flight Simulator Development Team.

There have been some compromises made, nevertheless, as we shall see.

 

Layers, we’ve got layers

So, if layers have been eliminated, then why are we still discussing them?

In fact, the concept of layers has now been displaced to the different terrain elements, each of which is assigned a layer number. This layer number simply establishes a priority for each element, ensuring that when the final ground tile is created, some elements will not be hidden by others. For example, roads have the higher layer number and therefore will always appear on top of rivers or streams.

The following is extracted from the Microsoft S.D.K.:

 

The following table lists how the layer values are distributed.

Type of Data  
Layer ID

Water Texture

0 – 3

Land Texture

4 – 7

General

8 – 100

The following table lists the layer values used in Flight Simulator 2002.

Type of Data  
Layer ID

Airport Skirtings and Parks

4

Shorelines

8

Streams

16

Dirt and Minor Roads

31

Major Roads

32

 

 

We can see that Microsoft indicates 101 (0 to 100) possible layers, more than sufficient for the creation of highly diverse terrain. However, for terrain elements, they only use 5 layer numbers: 4, 8, 16, 31, and 32. All the others are free and can be used by scenery designers.

It is very important to understand the importance of layers. When creating new terrain elements in Ground2K, you will have to assign them a layer number. This means that you must determine where they will appear (over or below) in relation to the other elements of terrain.

 

A  LOD of grids

The Flight Simulator world is geometrically broken down into what is called the Level of Detail, or LOD. This is nothing more than a simple grid that progressively gets smaller and smaller. It is used to delineate the elements that are drawn by the scenery engine.

For example, the following image is taken from the TMF Manual, by Christian Stock:

 

 

As you can see, a grid is divided into 4 equal parts. Each of these parts is then itself divided into 4 parts, and so on, down to the smallest level of detail in Flight Simulator.

Here is the Microsoft table showing the dimensions of most of the LOD grids:

 

 

The only ones that need be remembered for purposes of creating terrain (other than altitude mesh) are the following 

-         LOD13: This is commonly called an Area. An Area contains 256 x 256 points. By coincidence, this is also the size of Flight Simulator ground textures, so you can consider that an Area covers exactly the space of a ground texture. (By an even greater coincidence, ground textures are exactly 256 x 256 pixels in dimension.)

-         a point: As we have seen, there are 256 x 256 points in an Area. Each point represents approximately 4.8 meters – that is about 16 feet, for the metrically challenged – and is the smallest unit of display in the game. This means that, normally, Flight Simulator cannot represent any element of terrain scenery that is smaller. This is one of the more important compromises that were made in this version of the game. On the other hand, this limitation ensures that frame rates will not suffer in the case of complex scenery.

-         LOD8: This is known as a Cell. A Cell consists of a grid of 32 x 32 Areas. It is a basic unit used for the creation of terrain.

-         LOD5: This grid consists of 256 x 256 Areas and is the basic unit used for the creation of land classification scenery.

 

 Please note that the LOD grid is fixed to precisely defined longitude and latitude – it cannot be shifted around over Flight Simulator scenery. Ground2K always establishes a LOD grid (divided into Areas) over the work space of your scenery project.

 

 

Land and Sea

The basic ground tile in the Flight Simulator world is determined by what is called “land classification” and “water classification”.

Each Area receives either a land class or a water class value that then decides what ground texture should be used there.

 

Here is the list of land classes, taken from the Microsoft S.D.K.:

Table of Land Classification Values

Value

Land Classification Description

0

Ocean, Sea, Large Lake

1

Large City Urban Grid Wet (DO NOT USE)

2

Low Sparse Grassland

3

Coniferous Forest

4

Deciduous Conifer Forest

5

Deciduous Broadleaf Forest

6

Evergreen Broadleaf Forests

7

Tall Grasses And Shrubs

8

Bare Desert

9

Upland Tundra

10

Irrigated Grassland

11

Semi Desert

12

### Unused ###

13

Wooded Wet Swamp

14

### Unused ###

15

### Unused ###

16

Shrub Evergreen

17

Shrub Deciduous

18

### Unused ###

19

Evergreen Forest And Fields

20

Cool Rain Forest

21

Conifer Boreal Forest

22

Cool Conifer Forest

23

Cool Mixed Forest

24

Mixed Forest

25

Cool Broadleaf Forest

26

Southern Deciduous Broadleaf Forest

27

Conifer Forest

28

Montane Tropical Forests

29

Seasonal Tropical Forest

30

Cool Crops And Towns

31

Crops And Town

32

Dry Tropical Woods

33

Tropical Rainforest

34

Tropical Degraded Forest

35

Corn And Beans Cropland

36

Rice Paddy And Field

37

Hot Irrigated Cropland

38

Cool Irrigated Cropland

39

### Unused ###

40

Cool Grasses And Shrubs

41

Hot And Mild Grasses And Shrubs

42

Cold Grassland

43

Savanna (Woods)

44

Mire Bog Fen

45

Marsh Wetland

46

Mediterranean Scrub

47

Dry Woody Scrub

48

Dry Evergreen Woods

49

### Unused ###

50

Sand Desert

51

Semi Desert Shrubs

52

Semi Desert Sage

53

Barren Tundra

54

Cool Southern Hemisphere Mixed Forests

55

Cool Fields And Woods

56

Forest And Field

57

Cool Forest And Field

58

Fields And Woody Savanna

59

Succulent And Thorn Scrub

60

Small Leaf Mixed Woods

61

Deciduous And Mixed Boreal Forest

62

Narrow Conifers

63

Wooded Tundra

64

Heath Scrub

65

### Unused ###

66

### Unused ###

67

### Unused ###

68

### Unused ###

69

Polar And Alpine Desert

70

### Unused ###

71

### Unused ###

72

Mangrove

73

### Unused ###

74

### Unused ###

75

### Unused ###

76

Crop And Water Mixtures

77

### Unused ###

78

Southern Hemisphere Mixed Forest

79

### Unused ###

80

### Unused ###

81

### Unused ###

82

### Unused ###

83

### Unused ###

84

### Unused ###

85

### Unused ###

86

### Unused ###

87

### Unused ###

88

### Unused ###

89

Moist Eucalyptus

90

Rain Green Tropical Forest

91

Woody Savanna

92

Broadleaf Crops

93

Grass Crops

94

Crops Grass Shrubs

95

### Unused ###

96

### Unused ###

97

### Unused ###

98

### Unused ###

99

### Unused ###

100

Ocean, Sea, Large Lake

101

Large City Urban Grid Wet

102

Large City Urban Grid Dry

103

Large City Urban Non Grid Wet

104

Large City Urban Non Grid Dry

105

Medium City Urban Grid Wet

106

Medium City Urban Grid Dry

107

Medium City Urban Non Grid Wet

108

Medium City Urban Non Grid Dry

109

Large City Suburban Grid Wet

110

Large City Suburban Grid Dry

111

Large City Suburban Non Grid Wet

112

Large City Suburban Non Grid Dry

113

Medium City Suburban Grid Wet

114

Medium City Suburban Grid Dry

115

Medium City Suburban Non Grid Wet

116

Medium City Suburban Non Grid Dry

117

Small City Suburban Grid Wet

118

Small City Suburban Grid Dry

119

Small City Suburban Non Grid Wet

120

Small City Suburban Non Grid Dry

121

Large City Highrise

122

Ice

123

Inland Water (DO NOT USE)

124

Ocean Inlet (DO NOT USE)

125

Non Perennial Inland Water (DO NOT USE)

126

Non Perennial Inland Sea (DO NOT USE)

127

Reef

128

Grass

129

Arid

130

Rock

131

Dirt

132

Coral

133

Lava

134

Park

135

Golf Course

136

Cement

137

Tan Sand Beach

138

Black Sand Beach

139

Airfield1 (DO NOT USE)

140

Airfield2 (DO NOT USE)

141

Rock Volcanic

142

Rock Ice

252

Custom Texture with All Seasons

253

Custom Texture

254

Transparent

255

Invalid


A land class is not the equivalent of a ground texture, however. In order to take into account variations in ground textures that exist in different parts of the world (for example, a large city in Asia does not look the same as a city in the Americas),  a land class value will use different ground textures depending on where in the world it is.

In principle, the world is divided into 10 different regions (A-Europe, B-North America, C-US Red Desert, D-Central and South America, E-Africa, F-Asia and Pacific, G-Australia, H-Antarctic, I-Arctic, J-North Tundra Belt), and each should have its own complete set of ground textures. However, all ground textures were not completed in time to ship with this version of Flight Simulator. For the moment, mostly North American ground textures are available, and even some of those were not finished.

This means that when you assign a land class value anywhere in the world, you will usually get North American ground textures. 

No doubt, the Flight Simulator Development Team is working diligently at this very moment on this matter, and the next version of Flight Simulator will contain a greater variety of ground textures.

Water class is slightly less complicated. Here is the list of water classes:

Water Texture Classification 

Starting Number

000

 

Water Texture Description

001

Shallow Inland Water–Blue

002

Deep Inland Water–Blue

003

Ocean Inlets–Blue

004

Non Perennial Inland Sea–Blue

005

Non Perennial Inland Water–Blue

006

Outflow Water – Blue

 

 

007

Shallow Inland Water–Brown

008

Deep Inland Water–Brown

009

Ocean Inlets––Brown

010

Non Perennial Inland Sea–Brown

011

Non Perennial Inland Water–Brown

012

Outflow Water–Brown

 

 

013

Shallow Ocean Water 1–Class1 (High Plankton Concentration)

014

Shallow Ocean Water 2–Class1 (High Plankton Concentration)

015

Shallow Ocean Water 3–Class1 (High Plankton Concentration)

016

Shallow Ocean Water 4–Class1 (High Plankton Concentration)

017

Medium Depth Ocean Water–Class1 (High Plankton Concentration)

018

Deep Ocean Water–Class1 (High Plankton Concentration)

 

 

019

Shallow Ocean Water 1–Class2 ( Med High Plankton Concentration)

020

Shallow Ocean Water 2–Class2 ( Med High Plankton Concentration)

021

Shallow Ocean Water 3–Class2 ( Med High Plankton Concentration)

022

Shallow Ocean Water 4–Class2 ( Med High Plankton Concentration)

023

Medium Depth Ocean Water–Class2 ( Med High Plankton Concentration)

024

Deep Ocean Water –Class2 (Med High Plankton Concentration)

 

 

025

Shallow Ocean Water 1–Class3 (Med Low Plankton Concentration)

026

Shallow Ocean Water 2–Class3 (Med Low Plankton Concentration)

027

Shallow Ocean Water 3–Class3 (Med Low Plankton Concentration)

028

Shallow Ocean Water 4–Class3 (Med Low Plankton Concentration)

029

Medium Depth Ocean Water–Class3 (Med Low Plankton Concentration)

030

Deep Ocean Water –Class3 (Med Low Plankton Concentration)

 

 

031

Shallow Ocean Water 1–Class4 (Low Plankton Concentration)

032

Shallow Ocean Water 2–Class4 (Low Plankton Concentration)

033

Shallow Ocean Water 3–Class4 (Low Plankton Concentration)

034

Shallow Ocean Water 4–Class4 (Low Plankton Concentration)

035

Medium Depth Ocean Water–Class4 (Low Plankton Concentration)

036

Deep Ocean Water –Class4 (Low Plankton Concentration)

 

 

037

Shallow Ocean Water 1–Class1 (High Plankton Concentration), Tropical

038

Shallow Ocean Water 2–Class1 (High Plankton Concentration), Tropical

039

Shallow Ocean Water 3–Class1 (High Plankton Concentration), Tropical

040

Shallow Ocean Water 4–Class1 (High Plankton Concentration),Tropical

041

Medium Depth Ocean Water–Class1 (High Plankton Concentration), Tropical

042

Deep Ocean Water –Class1 (High Plankton Concentration), Tropical

 

 

043

Shallow Ocean Water 1–Class2 ( Med High Plankton Concentration), Tropical

044

Shallow Ocean Water 2–Class2 ( Med High Plankton Concentration), Tropical

045

Shallow Ocean Water 3–Class2 ( Med High Plankton Concentration), Tropical

046

Shallow Ocean Water 4–Class2 ( Med High Plankton Concentration), Tropical

047

Medium Depth Ocean Water–Class2 ( Med High Plankton Concentration), Tropical

048

Deep Ocean Water –Class2 (Med High Plankton Concentration), Tropical

 

 

049

Shallow Ocean Water 1–Class3 (Med Low Plankton Concentration), Tropical

050

Shallow Ocean Water 2–Class3 (Med Low Plankton Concentration), Tropical

051

Shallow Ocean Water 3–Class3 (Med Low Plankton Concentration), Tropical

052

Shallow Ocean Water 4–Class3 (Med Low Plankton Concentration), Tropical

053

Medium Depth Ocean Water–Class3 (Med Low Plankton Concentration), Tropical

054

Deep Ocean Water –Class3 (Med Low Plankton Concentration), Tropical

 

 

055

Shallow Ocean Water 1–Class4 (Low Plankton Concentration), Tropical

056

Shallow Ocean Water 2–Class4 (Low Plankton Concentration), Tropical

057

Shallow Ocean Water 3–Class4 (Low Plankton Concentration), Tropical

058

Shallow Ocean Water 4–Class4 (Low Plankton Concentration), Tropical

059

Medium Depth Ocean Water–Class4 (Low Plankton Concentration), Tropical

060

Deep Ocean Water –Class4 (Low Plankton Concentration), Tropical

 

There are no regional variants of water classes, and all the water textures are available except for number 012. However, you should be aware of the different types of water class textures grouped by depth.

 

From the Microsoft S.D.K.:

Water Depth Breakdown

To give greater visual control, the water was categorized by depth, plankton concentration, and tropical. The depth of the water defined in the table below tends to dictate the darkness of the water color: the deeper the water, the darker the texture. The plankton concentration determines the amount of green in the water color:  the more plankton, the greener the water. The tropical waters were highlighted because they tend to have a more vibrant color. 

Shallow Ocean Water 1: 0-5m
Shallow Ocean Water 2: 6-15m
Shallow Ocean Water 3: 16-30m
Shallow Ocean Water 4: 31-50m
Medium Depth Ocean Water: 51-80m
Deep Ocean Water: >80m

 

 

 

How It Works

 

Since Ground2K is a drawing tool, you will normally provide an image that will serve as a background on which to trace the terrain elements that you desire. 

This background image can be a map, an aerial picture, a screenshot of Flight Simulator, or any other image that you want. Picture size is limited to 10 000 x 10 000 pixels, and the larger the picture, the longer it will take to load in Ground2K. If your image is larger, either reduce the size to below this limit or break up your image and create different projects.

The image MUST be in bitmap format. No JPEG or TIFF allowed.

In addition, you will need the geographic coordinates of 2 points on that background picture. The coordinates can be the northwest and southeast corners of the image, or any 2 points within the picture that are in its northwest and southeast parts.

Once you have created the background, you would normally exclude the unwanted elements of the default terrain that will be replaced by new terrain.

Then, simply draw the new elements.

In this example, you will learn: 

            -         to create a background image;

-         to create a new project in Ground2K;

-         to exclude default terrain elements;

-         to create a new coast and shoreline;

-         to draw roads and railroads;

-         to create a lake;

-         to create a textured polygon;

-         to modify the land and water class.

 

The background image

Whether you desire to modify coasts, draw rivers or roads, or add bodies of water, you will most likely use a detailed image as a guide.

Here, Monaco was chosen for the project. As you can see, the default scenery for Monaco is somewhat deficient.

 

 

However, it should really look like this:

 

 

Very good and well-detailed maps can be found with a quick search of the internet..

 

Fortunately, this map also has lines of latitude and longitude on it, so alignment is particularly easy.

This map would be more than adequate as a background. Nonetheless, it is important to remember that the default coasts in Flight Simulator are often located rather far from where they should be in real life.

This means that if you were to use only a map as a guide, any terrain that you traced over it would most likely not be aligned with the default scenery.

For this reason, it may be interesting to take the map and place it over a screenshot of the default scenery.

 

Now, you can draw so that the new coasts or roads will line up well with the default terrain.

Tip: CellGrid by Richard Ludowise (available in the AvSim library) is a very useful tool that will place a LOD grid anywhere in Flight Simulator. This grid is divided into Areas that are numbered; you can easily visualize all the Areas that you wish to modify. Also, your screenshot can now be cropped to the exact Areas that you want. You can also get TDFCalc by the same author – with this little tool, you can slew anywhere in Flight Simulator and obtain the coordinates that you will need for Ground2K.

You can also try GridGen by Edgar Knobloch (also in the AvSim library) that will place a grid of latitude and longitude in Flight Simulator. With such a grid, you can very easily align a map to the screenshot.

In this project, we shall exclude the default shorelines, create new shorelines, add roads and railroads, add a lake and a textured polygon, and modify the land class.

 

Create a new project

When you launch Ground2K for the first time, you must provide a name for your project and declare the background bitmap and its coordinates. This process differs somewhat from standard Windows methods.

 

 

  1. To name your project, you must double-click in the white space on the first line.

    This will call up the standard Windows File dialog.




    Enter a name for your project and click on "Open".

    You will return to the New File window. Click on “NEXT”.

    Warning: Once you have clicked the “NEXT” button, you cannot  return to modify your project name.

    2.      To declare your background image, double-click in the white space on the second line and select your
           background image in the standard dialog..

  1. After selecting your image,  click on the button labeled “NW/SE coordinates in the map”. The map coordinates window will appear.



    Here you will indicate the coordinates of the image. By default, these points are located at the extreme northwest and southeast corners. If you wish to place these points elsewhere, simply click on the “NW point” button and click on the image to place the new location. Do the same with the “SE point” button. The new points should be located in the northwest and southeast parts of the image.

    Ground2K expects coordinates in decimal degrees format (for example, 45.10986º). If you have this information in degrees:minutes:seconds format (45:06:35.50º), use the Degrees Calculator in the Tools menu of the main window to convert your coordinates to decimal degrees.

    If you are unable to obtain coordinates for your background image, simply launch Flight Simulator and slew to the location of any landmark in the default scenery, for example, highway intersections, a bend in a river, the end of a lake, etc. Use these coordinates for the corresponding locations in your background image. Make sure that these coordinates correspond roughly to the northwest and southeast parts of the image.

    Once you have entered the coordinates of your image, click OK to return to the New File page.

  2. The coordinates in both decimal degrees and degrees:minutes:seconds will be displayed. Click “Next” to continue to the following section.

    Note: If you wish  to modify the coordinates of your image after having clicked on "Next", simply use the "Coordinates of the map" option in the Parameters menu.

  3. You must provide a name for the scenery bgl that will be created. Double click on the white zone and enter a name, for example, “Monaco”.

  4. You must also provide a name for the exclude bgl.  Double click on the white zone and enter a name, for example, “0_Monaco_exclude”.

    Note: Flight Simulator must read the exclude bgl first before any other terrain bgl. By placing a zero (0) before the name of your exclude bgl, you can avoid any potential errors.

  5. Finally, in the Land Class and Water Class section (LC and WC);

    - check “Update .raw general file”. Any modifications that are made to land class will now be registered;

    - select a directory for the raw file. The raw file is the separate image containing land class assignments. You could, for example, select the “Temp” folder in the Ground2K directory;

    - select a directory where the land class bgl will be created, for example, the Ground2K directory.

    Warning: Failure to provide all information will generate an error.

  6. When you are finished, click OK to return to the main window in Ground2K.

.

The work space 

At this point, your background image will appear in the main window and you can begin to work on terrain.

 

It is very simple to use Ground2K. Just click on the appropriate icon in the toolbar.

The dashed lines over the image correspond to the LOD grid divided into Areas.

The status bar at the bottom indicates:

-         the x,y position of the mouse pointer relative to the image dimensions;

-         geographic coordinates in both decimal degrees and degrees:minutes:seconds;

-         the coordinates of the corresponding Cell;

-         the coordinates of the Area;

-         the x,y position of the mouse pointer relative to the Area (points 0 through 255);

-         the custom name of the ground tile for those who are making custom textures.

 

Excluding terrain

To exclude a terrain element, you must exclude the layer number assigned to it.

Type of Data  
Layer ID

Airport Skirtings and Parks

4

Shorelines

8

Streams

16

Dirt and Minor Roads

31

Major Roads

32

For example, all major roads have a layer number of 32. Therefore, to exclude a major road, you must exclude layer 32. All terrain elements in that layer will be excluded.

Exclusions are applied separately to each Area. You must determine all the Areas where you will exclude terrain.

  1. Click on the “Exclude in Areas” icon     on the toolbar.

  2. Double click within the Area where you want to exclude terrain. (In this case, we wish to exclude the default shoreline. So, we double click in each Area where we wish to create a new shoreline.) This brings up the Exclude window.



  3. Place a check mark next to the type of terrain that should be excluded. (In this example, we shall exclude shorelines before creating the new Monaco coast.)

  4. Click OK to create the exclusion.

  5. Repeat the process for all Areas where you wish to remove the terrain element.

 

 

Drawing in Ground2K

 

When creating new terrain features in Ground2K, you will basically draw 2 different shapes: polygons and lines.

 

Polygons - A polygon is a closed many-sided figure. It can contain land (a Land Mask), water (a Water Mask), or a texture of your choice. You can assign a Land Class value to the polygon and it will show the respective ground texture along with all its seasonal variants and autogen. Or, you can provide textures of your own.

Often, you will draw only part of the polygon; for example, a new coast (Land Mask) may be a complex curve that you do not close. Ground2K will always close this sort of polygon by drawing a straight segment from one end of the curve to the other.

A polygon can be drawn in any sense that you wish, that is to say, in a clockwise or anti-clockwise direction. Ground2K will fill the interior of the polygon with land, water, or a texture according to your choice.

Polygons may not cross over themselves, or they will generate an error in Ground2K. For this reason, it is best not to try to close a polygon yourself, as you risk crossing the ends over each other. If you are drawing a closed polygon (for example, a lake or an island), bring the ends close to each other without letting them touch and Ground2K will automatically close the polygon for you.

 

Lines - A line can be a road, a shoreline (beach, riverbank, lake bank, etc.), a stream, a railroad, for example.

Some types of lines (shorelines) have a texture with a side that faces land and another side that faces water. Often, the water side has a wave effect. For this reason, shorelines should be drawn so that land is on the right-hand side of the line as you are drawing it. This will ensure that the shoreline faces the right way and that the wave effect appears in the water, not the land.

All other sorts of lines (roads, railroads, streams) can be drawn in any direction that you choose.

Lines may cross over themselves without generating errors.

 

 

The Properties window for Polygons and Lines

 

Whether you draw a new coast, a road, a lake, or any other terrain feature, you will have to assign the properties for that element in the Properties window.

 

 

On the Main tab, you can choose the following options:

Poly/Line/Shore section

  1. Poly without shore - this could be a coast, an island, a lake, a river, etc. It is not surrounded by a shoreline (although you can draw the shoreline in a separate step), and can be either filled with land (Land Mask), water (Water Mask), or a texture (VTP, i.e., Vector-Based Textured Polygon).

  2. Poly with shore - you could draw your coast, lake, or island first and then draw the shoreline around it, but Ground2K can automatically draw a shoreline along the edge of your polygon in one operation, if you wish.

  3. Line/LakeShore - choose this if you draw the shoreline separately, or if you draw a road, stream, railroad.

  4. Coastline - this option allows for the creation of a coastline (for example, a beach) and places water (Water Mask) automatically on the correct side of the line. The elevation of the coastline/water can also be determined here.

 

Type_Poly section

If you have chosen either Poly without shore or Poly with shore, then you must choose one of the following:

LWM Poly - LWM (Land/Water Mask) can be either a body of land or a body of water. It always reveals the underlying land class or water class. The water is true Flight Simulator floatable water.

VTP2 Poly - this type of polygon can be a texture of your choice, or you can provide all seasonal variants of the texture (Winter, Hard Winter, Spring, Summer, Fall, Night Lighting). You can also assign a land class value to this type of polygon, in which case the respective ground texture will be displayed with all its seasonal variants and complete autogen buildings and trees.

VTP1 Poly - resembles the previous option, except that autogen does not appear. However, VTP1 is more flexible in the placement of textures, and allows you to resize your texture and move it around within the polygon.

 

 

Lines tab

 

 

If you have chosen "Poly with shore", "Line/LakeShore" or "Coastline", then you must select from the following:

Line/Shore section - select the type of line that you desire (different types of shorelines, streams, roads)

Land on the right - if you have chosen a line with a wave effect (i.e., a beach), place a check mark here and draw your line in such a way that land is on the right-hand side as you are drawing

Join ends of line - place a check mark if you want Ground2K to close the line for you. This operation is valid only for the line, not for any accompanying polygon.

Width - insert a value in meters, although the line will only display about 2/3 of this value in Flight Simulator because of transparencies in the textures

Layer - assign a layer for the line

 

LWM tab

 

If you have chosen "Poly without shore" or "Poly with shore" and indicated that it is an "LWM Poly", then you must select the type of mask that you desire here, land or water.

You can also assign a new elevation value to your LWM polygon - this forces the underlying altitude mesh to the new elevation. A value of "-9999" will keep the elevation unchanged from the underlying altitude mesh - that is, your polygon will follow the mesh altitude.

 

VTP1 Polys tab

 

If you have chosen "Poly without shore" or "Poly with shore" and indicated that it is a "VTP1 Poly", then you would choose either to assign a land class value to the polygon or indicate the names of the textures that you want to fill the polygon.

 

VTP2 Polys tab

If you have chosen "Poly without shore" or "Poly with shore" and indicated that it is a "VTP2 Poly", then you would choose either to assign a land class value to the polygon or indicate the names of the textures that you want to fill the polygon.

 

 

Create a new coast

There are 2 distinct elements: a coast (a polygon filled with land - Land Mask) and a shoreline between the land and the water. 

You could first draw the coast (a polygon filled with land), then the shoreline along the edge of the coast polygon. But, Ground2K can easily create both elements at the same time. Just simply draw the shoreline; Ground2K will create the coast polygon on one side and fill it with land, and automatically place the shoreline on the edge of the land.

  1. Click on the “Road/river/lake” icon      on the toolbar. All the related icons will now be available.

  2. Click on the “New object” icon.  

  3. Place the mouse at the initial position of your new coast.

    Tip: You should draw your combined coast/shoreline in such a way that land is on the right-hand side of the line. This will ensure that the shoreline texture is displayed with correct orientation and that wave effects appear on the water side of the texture.

    Also, you would usually begin drawing the new shoreline at the edge of the first Area where it will appear. However, in order to avoid any gaps between the new and the default shorelines, you might consider starting your line in the adjoining Area, where it will overlap the default shoreline.


  4. Click once to place the first point of your new shoreline. At this point, the Attributes page for Polygons/Lines will appear.



    These pages contains all the options for every type of line or polygon that you will draw in Ground2K.

  5. Since we are drawing a coast (Land Mask) with a shoreline (Line), select “Poly with shore”.

    Then, in the "Type_Poly" section, choose "LWM Poly".






    In the "LWM" tab, select "Land", since we want to fill this coast polygon with land.






    Note: If your project consists of a coast that is far offshore from the default coast or if it is land in the middle of  water (for example, an island), you may find that nothing will show up in Flight Simulator. The reason is that land must first be declared in an Area and then a land class value assigned to it for it to appear.

    To remedy this, you should create an LWM  polygon encompassing all that you want as land. Then, choose the Land Class icon and assign a land class value to the respective Areas.


  6. In the “Line/Shore” tab, you can choose the type of shoreline that you desire.





    For this project, we choose “Ocean/white sand/ perennial” which has a wave effect linked to it.

    Note: For the moment, no matter what type of shoreline you choose will always result in the same beach shore being used. It seems that the different shore textures were not finished in time to ship with this version of Flight Simulator.

    Nonetheless, we can imagine that future versions of the game will provide all possible shorelines. Therefore, it would be wise to choose carefully now so as to make certain that your new terrain will appear correctly in the next version of Flight Simulator.


    Check “Land on the right”  and be certain to draw your shoreline with land on the right-hand side of the line. This will ensure that the shore texture faces the right way and that any wave effects will be in the water side, not the land side of the texture.

    Uncheck “Join ends of line”. Ground2K can automatically close a line; for example, if you were drawing a shore around a lake or an island, you might want a continuous shore, and so you would select this option. However, in this instance, the shoreline is placed on the edge of the coast polygon, and selecting this would result in a line of beach going through the land from one end of the new coast to the other. Make sure that this is NOT checked.

    In “Width”, indicate how wide you wish the shoreline to be. It is thought that this is measured in meters, however the width in Flight Simulator may appear smaller. This is because part of the texture used for shorelines contains a transparent part - the apparent width will therefore be around two-thirds of the indicated width..

    Note: The default shorelines seem to have a width of about 60, so you may want to use this. For a long straight beach, this value is quite acceptable. However, for a highly-detailed shoreline that curves in on itself often, such as Monaco, such a wide beach will overlap itself and eliminate fine detail. For this example, it would be better to use a width of 20.

    In “Layer”, indicate the layer number for the new shoreline.

    Note: The default shoreline (layer number 8) has been excluded in the Areas of the project. If you place the new shoreline in that layer, it too might  be excluded. To avoid potential problems, choose a different layer number, for example, 9.

  7. Click OK to return to the main window.
  1. Proceed to draw the shoreline. Click to place points along the line as needed until you arrive at the end. Use the "Zoom +" icon on the toolbar for enhanced detail.

    Warning: When you are drawing a polygon, avoid crossing the line over itself. This will generate an error. Simple lines, however, such as roads or streams  can cross over themselves.

    Tip: In order to avoid gaps between the end of the new shoreline and the default, extend the new shoreline into the next Area so that it overlaps the default.

  2. When you have finished drawing the line, press ESCAPE to exit this function.

 

Draw roads and railroads

A road is considered a line, and the procedure for creating it is comparable to the above. The only difference is that there is no polygon associated with this line.

 

  1. Click on the “Road/river/lake” icon      on the toolbar. All the related icons will now be available.

  2. Click on the “New object” icon.  

  3. Place the mouse cursor at the initial position of your new road. Click once to place the first point of your new road. At this point, the Attributes page for Polygons/Lines will appear.



  4. In the first section, “Poly/Line/Shore”, you should indicate the nature of what you are drawing.

    Since a road is a line, select “Line/LakeShore”.

  5. In the “Line/Shore” tab, you can choose the type of road that you desire (divided or undivided median, asphalt or dirt, 2 to 10 lanes, etc.).





    Uncheck “Join ends of line”.

    In Width, choose a value.

    Tip: Many of the default major roads seem to have a width of 40, while minor roads may have a width of 20.

    In Layer, indicate the layer for this new road.

    Tip: Since we have not excluded any roads in this project, we could use the same layer number as the default roads. However, there are plenty of free layer numbers, and using a different value ensures that the new road will not be excluded by any other project that happens to cover the same Area. For instance, we could use layer number 33 for new roads.



    There are no polygons created in a road, so nothing else need be specified on the Attributes page.

    Click OK to return to the main window.

  6. Proceed to draw the road. Click to place points along the line as needed. Use the "Zoom +" icon on the toolbar for enhanced detail.

  7. When you have finished drawing the line, press ESCAPE to exit this function.

    Warning: Roads (and railroads) eliminate all autogen buildings and trees in their path.

    T
    ip: You may not be satisfied with the appearance of the roads in Flight Simulator. Various people have provided replacement road textures that improve their look – just search in the AvSim library.


Railroads can be drawn in the same manner as roads. As there is not at present a distinct railroad texture for this terrain element, you may want to use a dirt road to represent them.


Tip: The author of Ground2K, Christian Fumey, provides a railroad texture for your use. Place it in the FS2002/scenedb/World/texture folder and see if you like it.

 

 

 

Create a lake

 

There are no lakes in Monaco, but there are plenty of pools (not including the fountain in front of the Casino.)

 

 

A lake is simply a polygon with or without a shoreline. In this case, we shall draw the pool without a shoreline.

 

  1. Click on the “Road/river/lake” icon      on the toolbar. All the related icons will now be available.

  2. Click on the “New object” icon.  

  3. Place the mouse cursor at the initial position of the pool polygon.




    Click once to place the first point. At this point, the Attributes page for Polygons/Lines will appear.




  4. In the first section, “Poly/Line/Shore”, you can choose the type of polygon, in this case, “Poly without shore”. In the "Type_Poly" section, choose "LWM Poly".


    Note: If you were drawing a lake with a shoreline, you would select “Poly with shore” in the first section and choose the attributes of the shoreline in the “Lines” section.

    In the “LWM” tab, select “Water”.





    Click OK to return to the main window.

  5. Proceed to draw the pool. Click to place points along the line as needed.

  6. When you have finished drawing the line, press ESCAPE to exit this function.

 

 

Let’s jump ahead for a moment and take a look at the final result.

 

 

We certainly have a body of water in the right place. And you could land your amphibious helicopter in it. But, unfortunately, it looks very little like a pool, and a lot like the harbor water next to it.

In this case, it might be better to lay down a textured polygon with a nicer color that looks more like a pool. This would not be water, but it would look more appropriate.

 

Create a textured polygon

There are two types of textured polygons (VTP, or Vector-Based Textured Polygons):

a)      The first type (VTP2) can receive a land class value (and display a default ground texture). Autogen will appear as normal over this polygon.

Or, you can assign any other texture that you wish and provide seasonal variants – the texture will change in appearance through the year.

b)      The second type (VTP1) can use a land class value, but there will be no autogen displayed. You can also use any texture of your choice and provide seasonal variants.

In addition, this type of polygon has the advantage that you can shift the position of the texture so that only a part of it is displayed in the polygon. This possibility is not present in the first type of textured polygon.

We shall create the pool using the second type of textured polygon.

Note: We refer to the first type and the second type of textured polygons because of the order in which they appear on the Attributes page in Ground2K. Be aware that the first type of textured polygon is, in fact, a VTP2 polygon while the second type is a VTP1 polygon.

Warning: While you can use any image as your texture, it must be a bitmap (no JPEG or other allowed) in either 8-bit color (256 color) or in DXT1 format (the standard format for ground textures.) Any other format for the texture will either prevent Flight Simulator from launching or crash it. You may even find that some 8-bit color bitmaps will crash the game. You are safest using DXT1 bitmaps. Place your textures in the FS2002/Texture folder.

 

We could first delete the pool polygon that was drawn in the above procedure, then draw it again and specify its attributes as a textured polygon.

But, this is not necessary. We can keep the polygon and simply modify its attributes.

To modify the attributes of a line or polygon, just select it and right click.

 

  1. Click on the “Road/river/lake” icon      on the toolbar. All the related icons will now be available.

  2. Click on the “Object selection” icon.  

  3. Double click on the pool polygon to select it.

  4. Right click to bring up the Attributes page.



  5. In the “Poly/Line/Shore” section, make sure that “Poly without shore” is selected.

    In the "Type_Poly" section, choose “VTP1 poly”.

    Note: The “VTP 1/VTP2 Layer” zone determines the layer number for both the “VTP1/Polys” and the “VTP2/Poly” tabs. It defaults to a value of 7; leave it at this value.

    In the "VTP1 Polys" tab, make sure to select the first section, "VTP1/Poly/Special".





    Click OK to return to the main window.

  6.  This type of polygon must have its texture assigned using another part of the toolbar. First, you must select the texture, then assign it to the polygon.

    Click on the “Textures and linked polys (VTP1)” icon      on the toolbar. All the related icons will now be available.

  7. Click on the “New texture (VTP1)” icon.  

  8. Click on the polygon that will have a texture assigned to it.

    This brings up the “Texture modification/creation” window.



  9. Double click on the first white zone.

    This brings up the “Find a texture” window.



    Select your texture and click OK.

  10. Click OK in the “Texture modification/creation” window. You will now return to the work space.



  11. At this point, you can move the texture around the work space or resize it if you wish.

    To move the texture, just move the mouse cursor. Fix the location by clicking.

    To resize the texture, grab one of the edges or corners with the cursor and drag.

    Warning: Make sure that the texture covers all of the polygon. If not, this will generate an error.



  12. You must now assign the texture to the polygon.

    Click on the “Link a poly to the selected texture (VTP1)” icon.  

  13.  Double click on one of the edges of the polygon to select it. It will change to a yellow color.

  14. Right click to bring up a dialog confirming the texture assignment. Click OK.

 

Let us now take a look at the result.

 

  This looks more like a pool than the previous method.

 

Warning: Flight Simulator may crash if it cannot find all required variants of textures. Texture variants are as follows:

If you encounter a problem, simply indicate all variants of your texture in the "Texture modification/creation" window and place the textures in the FS2002/Texture folder.

 

Imbrication: overlapping polygons

On occasion, you may draw polygons that overlap each other, that is to say, that only partially cover another polygon. For example, you may draw a polygon representing an island, then draw another polygon that is a lake or river within that island but that leads out to the sea.

Ground2K can easily handle overlapping polygons of this sort. Simply use the "Imbrication" option in the Attributes page.

First, determine how many polygons overlap and which are the farthest inside and the farthest outside.

All the polygons must then receive a name consisting of a two-letter identification common to all the polygons and a 2-digit number separated from the letters by an underscore.

For example, a group of polygons representing the Étang de Berre north of Martigues and its outlet to the sea might be called:

EB_01
EB_02
EB_03
etc.

Numbers do not have to be sequential, so that the following is also valid:

EB_12
EB_35
EB_108
etc.

The polygon farthest inside must receive the smallest number and the polygon farthest outside must get the biggest number. Place the identification for each polygon in the "Imbrication" zone in the Attributes page for that polygon.

 

Note that you do not have to use "Imbrication" for polygons that are completely enclosed within another - Ground2K will automatically determine the proper placement in such a situation. 

 

 

Modify land and water class

Land Class is what determines the type of ground texture that is used in the scenery. Water Class does the same for the water.

Note: When changing Land Class, you may be tempted to choose the new values based on the image of the ground texture that is associated with it. Nonetheless, keep in mind that this version of Flight Simulator shipped with a very limited number of ground textures. Future versions of the game will, no doubt, have a much greater variety of ground textures.

This means that your scenery will most likely look very different in the future Flight Simulator from what you choose now. You might be advised to choose your Land Class values based not on the image of the ground texture, but rather on the description of each Land Class value.

 

        1.      Click on the “LandClass” icon      on the toolbar.

        2.      Double click on each Area where you wish to change the Land Class.

            This will bring up the Land Class properties window.

           

        3.      Select the Land Class of your choice.

               Click OK.

        4.      Repeat for all Areas you wish to change.
               To view the assigned ground textures on the work space, click on the "Show/hide textures" icon.

 

Note: You should be aware that Land Class is not assigned to the Area itself.

All Land Class assignments are made to the vertex or corner of four adjoining Areas. Each Area then blends the Land Classes of its four corners to create the distinct ground tile. This is done to avoid abrupt changes in the ground as it transitions from one ground texture to another.


Note: Land Class values can only be assigned in Areas where there is land. Assigning a Land Class value in the middle of the ocean will not result in the appearance of an island, for example. 

To obtain land where there is none in the default scenery, either draw a land polygon (LWM) or use the "Area attributes" icon on the toolbar to fill the Area with land. Then, assign a Land Class value to it.

 

Note: Some Land Class values are, in fact, water. Undoubtedly, this option provided the Flight Simulator Development Team with greater flexibility.

 

To modify water classes, proceed as above, except that you should choose the “WaterClass” icon      on the toolbar.

             

 

 

 

Re-mesh

 

Ground2K provides a means of modifying the altitude mesh. This procedure does not create a new altitude mesh, but rather uses a property of LWM polygons - they can have an elevation value assigned to them that forces the underlying altitude mesh to the new altitude.

Ground2K creates a grid with the same horizontal separation as the LOD grid and allows you to place very small LWM polygons on it with new elevations.

 

1. To use this function, click on the Re-mesh icon,

2. Ground2K will now allow you to choose a LOD resolution (horizontal separation between the elevation points.) For best results, you should choose a LOD resolution that is close to that of the underlying altitude mesh. If you choose LOD 11 or 12, you may not see any change in Flight Simulator without modifying the fs2002.cfg file.

 

 

3. A grid with the chosen resolution will now appear over the work space.

 

 

4. To add a new elevation, just place the cursor over one of the vertices of the grid and click. This will bring up a window where you can enter the new value.

 

 

 

5. Enter your new value and press "Enter". A red cross will appear on the grid to show that there is an elevation value present.



Note: You should place your new elevation points at the vertices of the grid. There is no advantage in adding points between the vertices.

6. To modify an elevation value, place the cursor over the red cross and click to bring up the altitude value window.

7. To delete an elevation value, place the cursor over the red cross and press the "Delete" key.

 

 

 

 

The final result

After having drawn a total of 5 lines

-         1 for the combined coast and shoreline

-         3 roads and a railroad

-         a pool

this is what you get.

 

 

A more realistic representation of the world with very little effort required.

 

 

Saving and generating your scenery

Save your project in the usual manner, that is, use the menu item or the toolbar or the keyboard shortcut.

To generate your scenery, click on the “BGL generation” icon      on the toolbar.

Ground2K will create all the necessary bgls and deposit them in the relevant folder, most likely the Ground2K folder.

All scenery will be created in distinct bgls that contain the varying terrain elements:

 - xxxx_2.bgl -- contains the re-mesh LWM polygons

 - xxxx_3.bgl -- contains all other Land/Water Mask polygons

 - xxxx_5.bgl -- contains all VTP2 (textured) polygons

 - xxxx_7.bgl -- contains all VTP1 (textured) polygons

 - xxxx_9.bgl -- contains all lines (shorelines, roads, etc.)

 - xxxx_9nn.bgl -- if you have selected SCASM night lighting for your roads, this contains the SCASM code

 

Installing the scenery

Terrain scenery can be installed in the same manner as any other, that is, declare it in the Flight Simulator scenery library.

You can place all the bgls in a folder named “scenery” and place this in another folder with a name of your choice.

Land class and water class scenery have an important limitation. The folder containing land class or water class may not have an associated “texture” folder.

Flight Simulator reads the different terrain bgls in a very particular order. It may happen that new terrain elements will not be displayed if there are many different scenery projects in the same Area. To avoid any problems, you could separate the terrain bgls and declare them in the FS scenery library in the following manner, from the highest number to the lowest:

 - all exclude files in their own scenery folder

 - all land class and water class files in their own scenery folder

 - all mesh files

 - the terrain bgls

 

 

 

Common problems and errors

 

The following examples were taken from the AvSim forum dedicated to Microsoft Flight Simulator scenery design.

 

Background image

I get an error message: "Points to be verified"

Exclude

I exclude default roads, but my new roads don't show up

Lines

My new road (or beach) does not appear

My road (or beach) has narrow ends

My road (or beach) disappears at spots

I get an error message: "lake/curve : a curve crosses itself", but I drew a road, not a lake

My beach has waves on the land side

Polygons

I drew a new coast, but land shows up on the wrong side

I drew a new coast, but no land shows

I get an error message: "lake/curve : a curve crosses itself", but I am sure that it does not cross itself

 

 

Background image

Problem: I indicate the coordinates for my background image and get an error message: "Points to be verified".

Answer no. 1: The coordinates should be points that are either the northwest and southeast corners of your image, or points in the northwest and southeast parts of the image. Ground2K then calculates the location and span of your image from these coordinates. If the coordinates are not in the northwest and southeast parts of the image, the calculations will be erroneous.
Solution no. 1: Make sure that your coordinates are in the northwest and southeast portions of your image.

Answer no. 2: All longitudes EAST of the Greenwich meridian are positive - if they are WEST of Greenwich (this means you in the Americas), then they are negative and should be preceded by a minus sign (-). In the same manner, all latitudes NORTH of the equator are positive; SOUTH of the equator, they are negative and should be preceded by a minus sign (-). If you do not respect this format, Ground2K's calculations may be erroneous.
Solution no. 2: Indicate your coordinates using the proper format.

 

Exclude

Problem: I exclude default roads, but my new roads don't show up in Flight Simulator.

Answer no. 1:  Terrain elements are excluded by excluding the Layer number assigned to them. If you exclude a layer, and then create new terrain elements with the same layer number, you risk excluding your new elements as well.
Solution no. 1: Place your new terrain elements in a different layer from what you have excluded. For example, if you exclude major roads (Layer number 32), then place your new roads in Layer number 33.

Answer no. 2: Flight Simulator is somewhat demanding in the way that it reads terrain scenery. The Exclude bgl must be read first, before any of the other bgls, in order to avoid problems.
Solution no. 2: If you do not have a lot of terrain scenery projects, then you can probably just name your Exclude bgl in such a way that it is read first. For example, place a zero (0) at the start of its name (i.e., 0_xxxx_exclude.bgl). Or, follow the recommendations in the "Installing the scenery" section above, and create a separate folder for your exclude files - give this folder the highest number in the Flight Simulator scenery library.

 

Lines

Problem: My new road (or beach) does not appear.

Answer no. 1: The smallest level of detail in Flight Simulator terrain is 4.8 meters. Anything smaller will not be displayed. Given that a part of the texture displayed by a road (or beach or any other line) is transparent, it may be that there is a minimum width to the line below which it will not display.
Solution no. 1
: Always choose a width greater than 20 for your lines.

Answer no. 2: A line needs a certain number of Points in order to define it. A very short line without sufficient points will not appear.
Solution no. 2: Click numerous times to define sufficient points for your line.

 

Problem:  My road (or beach) has narrow ends.

Answer: We still do not understand all aspects of Flight Simulator terrain, in particular, how lines are formed. It seems that they need various points at their ends in order to have square ends.
Solution: When starting or ending a line, click numerous times - for example, click twice on the first point, twice on a spot that is one point away, etc. Do the same at the end of the line.

 

Problem: My road (or beach) disappears at spots.

Answer: A line requires a certain number of points in each Area, or it will not appear in the Area.
Solution: When drawing your line, make sure to click at least 3 or 4 times in each Area through which it passes.

 

Problem: I get an error message: "lake/curve : a curve crosses itself", but I drew a road, not a lake.

Answer: All terrain elements must be correctly defined in their Attributes window. By default, all curves are defined as "Poly without shore" - "LWM" - "Water". It can happen, while designing a long and complex project, that one forgets to modify the attributes for a curve and simply leaves the default settings.
Solution: Make sure that all terrain elements are correctly defined in their Attributes window.

 

Problem: My beach has waves on the land side.

Answer: Because certain types of shorelines have a land side and a water side, with wave effects, they must be drawn in a certain direction in order to avoid this problem.
Solution: Draw shorelines in such a way that land is on the right-hand side of the line as you draw it.

 

Polygons

Problem: I drew a new coast, but land shows up on the wrong side.

 

Answer: A coast is a polygon that is filled with land. When you draw a new coast, you usually only draw a part of the polygon and do not close it. Ground2K will always automatically close all polygons by drawing a straight segment from one end to the other. As you can see in the above example, this will create a polygon that is different from what is desired.
Solution: Extend the ends of your new coast in such a way that Ground2K will close it on the correct side, for example:

 

 

Problem: I drew a new coast, but no land shows.

 

Answer:  In order for land to show, there must be land defined there (either by drawing a land mask polygon - LWM, or filling the Area with Land through the Area Properties window) and then a land class value must be assigned. Without the land class value, no land will show.
Solution: Assign a land class value to all parts of your new coast.

 

Problem: I get an error message: "lake/curve : a curve crosses itself", but I am sure that it does not cross itself.

 

Answer: A coast is a polygon, and Ground2K will always automatically close the polygon by drawing a straight segment from one end to the other. As you can see in the above example, this results in a line going through the new coast, thereby crossing itself.
Solution: Extend the ends of your coast in such a way that the closing segment will not cross over any part of the polygon, for example:

 

 

 

 

 

 

Glossary

 

Altitude mesh - a 3-dimensional grid whose points represent elevations. The horizontal separation of the points is determined by the Level of Display (L.O.D.) resolution.

Area - a grid with a resolution corresponding to L.O.D. 13 and having approximately 1.2 kilometers to a side (although this varies with latitude). An Area covers exactly the space of a ground tile. It contains 256 x 256 Points.

BGL - Bruce Artwick Organization Graphics Library. Bruce Artwick was the original developer of Flight Simulator, and this is his file format for scenery within the game.

 

 



Cell - a grid with a resolution corresponding to L.O.D. 8 and containing 32 x 32 Areas.

Coast - should not be confused with a shoreline or a coastline. A coast is a polygon containing a land mask and is therefore declared as LWM.

Coastline - a distinct feature of Ground2K, a coastline is a line displaying the shore texture of your choice and also having water mask polygons (LWM) on one side of the line. Should be used only in specific circumstances where one wishes to replace pre-existing land with water, and place a shoreline at the same time.

Decimal degrees - a representation of geographic coordinates expressed as degrees and their decimal values, i.e., 45.10986º

Degrees:minutes:seconds - a representation of geographic coordinates expressed as degrees with 60 minutes to a degree and 60 seconds to a minute, i.e., 45:06:35.50º

Exclude - an operation permitting the removal of all terrain elements pertaining to the layer that is excluded. For example, excluding layer 32 will remove all major roads in the affected Areas.

Ground texture - Flight Simulator ships with a wide variety of textures representing different types of ground. They may have seasonal variants (Winter-no snow, Hard Winter-snow, Spring, Summer, Fall) as well as a Night Lighting version. In addition, they can come with up to 7 variants of each of the above in order to attenuate repetitious effects. Ground textures are used to create the ground tile and are called by the land class.

Ground tile - a ground tile completely fills an Area, and is created in the following manner: a) land class values are assigned to its 4 corners; b) depending on the region of the world, the season of the year, and whether it is day or night, the land class calls the corresponding ground texture; c) the 4 ground textures are blended within the Area; d) all terrain features (roads, rivers, lakes, shorelines, parks, etc.) are then inlaid to make a unique ground tile that is displayed in Flight Simulator.

Imbrication - from the Latin imbricare, to lay down like bricks or tiles, that is, to overlap. In this case, refers to polygons that can overlap each other, but must be properly identified within Ground2K in order to avoid errors.

Land classification - a geographical method of identifying land use throughout the world. Flight Simulator uses a simplified system representing major types of land use. Land class values are assigned to the scenery, and determine the type of ground that is displayed in the game.

Land Mask - a polygon that is filled with land, and displays the underlying land class value.

LWM - Land/Water Mask. See Land Mask and Water Mask.

Layer - all terrain elements are assigned a layer number that determines whether they are displayed above or below other elements in the ground tile.

Level of Detail - the coordinate grid used by Flight Simulator. A simple grid that is progressively reduced in size. The separation between its points determines its resolution.

Line - a curve that can represent specific terrain elements such as roads, shorelines, or streams. (In reality, a line displays a Vector-based Textured Polygon of the 2nd type.)

Line/LakeShore - an option in Ground2K that declares a curve as a road, stream, or shoreline.

L.O.D. - see Level of Detail

Mesh - a 3-dimensional digital model consisting of vertices and edges. In Flight Simulator, this term is commonly used to refer to altitude mesh.

Polygon - a closed many-sided figure. In Ground2K, a polygon can be a Land Mask, a Water Mask, or a Vector-based Textured Polygon. Ground2K will always automatically close any curve that is declared as a polygon by drawing a straight segment between the ends.

Poly with shore - an option in Ground2K declaring a curve as a polygon with an associated shoreline along the edge of the polygon. Should be used when drawing a body of land or water that has the same shoreline all along its edge, for example, a lake, an island, or a coast.

Poly without shore - an option in Ground2K declaring a curve as a simple polygon. This can be a Land Mask, a Water Mask, or a Vector-based Textured Polygon.

Point - the smallest unit of display for Flight Simulator terrain, representing approximately 4.8 meters. There are 256 x 256 Points in an Area.

Raw general file - a 257 x 257 pixel image file (in RAW format) used for creating land class scenery. Each pixel represents the vertex, or corner, of an Area, and the color value for that pixel corresponds to a land class value.

Re-mesh - a feature in Ground2K allowing modification of elevation points. Distinct from normal altitude mesh in that it uses a grid of very small LWM polygons to force the altitude mesh to a new elevation. Useful in fine tuning elevation in your new terrain.

Shoreline - a line that is a decorative element along the edge of an LWM polygon, a shoreline can be a beach, a riverbank, a lake bank, a harbor, or other types of shores.

Textured polygon - see Vector-based Textured Polygon

Vector-based Textured Polygon - a polygon that can contain textures of your choice or that can have a land class value assigned to it. Available in 2 similar, slightly different, forms: V.T.P.1 and V.T.P.2

V.T.P. - see Vector-Based Textured Polygon

V.T.P.1 - a Vector-based Textured Polygon of the 1st type, this polygon can display any texture of your choice, with seasonal variants, or you can assign a land class value, but no autogen will show. More flexible than V.T.P.2 because the texture can be resized and moved around within the polygon.

V.T.P.2 -a Vector-based Textured Polygon of the 2nd type, this polygon can display any texture of your choice, with seasonal variants, or you can assign a land class value with full autogen display.

Water classification - a method within Flight Simulator for classifying different types of water. Water class values call their corresponding water textures.

Water Mask - a polygon that is filled with water and displays the underlying water class value.

 

 

Support

No doubt, after making your first modification of terrain with Ground2K, you will have questions, and perhaps a problem will have arisen. This is to be expected, as this guide does not cover all aspects of terrain modification or all the possibilities of Ground2K.

My sincere apologies – I am unable to provide support of any kind for lack of free time. Please do not write.

However, please do not abandon your project. Ground2K is very easy to use and there are simple solutions for all possible problems.

For answers to your questions or solutions to your problems, please consult the AvSim forum dedicated to Microsoft Flight Simulator scenery design ( http://forums.avsim.com ). There, some kind soul, perhaps even myself, will be glad to help.

Please do not contact Christian Fumey, the author of Ground2K, concerning this document. He did not take part in its elaboration and is not responsible for its content.