Polygon (Poly)
The polygon is the most important shape in scenery design. A polygon is a closed figure that is either colored or textured. It is highly recommended to enable texturing, since textured polygons add to the realism. Polygons are great for surfaces that cover large areas like taxiways, the grass surface and the pavement at terminals.
You don't have much influence on how a texture is applied to the polygon's surface. A polygon texture is tiled, the texture's Y axis being aligned with the 'North-South' axis. Pixel size depends on the scale factor chosen for polygons. You can set the scale for all polygons in the FILE\ PROJECT settings... menu item (one pixel width/height[meters] = scale unit [meter/unit]). In case you want a specific part of a texture to cover a polygon, please use the TEXPOLY tool instead.
When textured, seasonal and night effects can be enabled. Use seasonal effects for grass surfaces for example.
Notes on drawing polygons
Polygons must be convex or simple concave. Do not draw polygons with intersecting edges. Such polygons will likely not show all. A polygon's outline should be kept as simple as possible, avoid excessive use of 'corners' and 'turns'. If you need to make a complex surface, split it into simpler polygons. A polygon should not have its diameter exceeding 1000 meters (about 3000'). Larger polygons lead to an irregularly hazed surface in FS.
Setting polygon properties
In order to access the settings dialog, make sure only one polygon is selected. Double-click anywhere on the map to open the dialog. You can also access the settings through the SELECTION\ PROPERTIES... menu item or by left-clicking the polygon handle.
Enter a comment in the COMMENT box. Comments are only there to help you identifying shapes. They appear in the SCASM source file. This is useful in case some hand coding is needed.
Checking the COLORED option will disable texturing. The polygon's surface will be filled with a plain color. Set that color by clicking on the PICK COLOR box. A standard RGB dialog will be shown. Here is a tip in case you want the get the color that you have set for another shape. Access that shape's settings and click on its color box. In the RGB color dialog, click the ADD COLOR button on the right. This will copy the shape's color to one of the 16 CUSTOM COLORS on the left. The RGB dialog will 'remember' the added color and make it available whenever you open it again.
Set the polygon's transparency by moving the slider. This feature can be interesting for simulating a light spot on the ground at night.
FS usually changes the color's brightness depending on the time of day. At night, all colors are almost black, gaining full brightness around noon. If you want the color to keep its brightness anytime, check the CONSTANT BRIGHTNESS option.
To select a texture, click on any of the listed files. A preview will be visible on the left. The textures listed are those found in the folder you can set in the FILE\ PREFERENCES... menu item (Click the DIRECTORIES tab). The default TEXTURE folder is in GroundMaker's directory. These textures are also used for OpenGL rendering (when enabled).
If you want seasonal and night light effects to be applied to your shape, check any of the options on the left. FS will then load another texture depending on the chosen season or time of day. The texture you select in the list is the summer and day texture by default. Enabling the Spring option, for example, will force FS to load another texture in spring.
You will find more info on textures by reading the TEXTURE topic.
The VISIBILITY settings influence the shape's appearance. The most important option is the visual RANGE. Is the viewer's distance to the shape's center greater than the value set here, the shape will be not drawn. You should pay great attention to those values, since setting too large ranges for all shapes will lead to a bad performance of FS. The bottom line is: the less FS has to draw, the higher frame-rates. Small details cannot be seen from far away anyway, so use short ranges for such. To give you an idea what reasonable values are, check out the list below:
Type of surface Visual range (meters) Airport grass polygon 15,000 - 20,000 Tarmac polygon (e.g. large surface at terminals) 10,000 - 15,000 Long taxiway 6,000 - 12,000 Short taxiway 4,000 - 6,000 Very short taxiway 3,000 - 5,000 Taxiway safety area 2,000 - 3,000 If you are not confident with the metric system, simply use the CONVERTER to convert miles, feet, ... to meters.
Sometimes it is necessary to hide a shape at certain times of day. Push any of the the three buttons (DAY, NIGHT, DUSK/DAWN) to make the shape visible at the chosen time of day. For example, releasing the DAY button will make the shape invisible at daytime.
GroundMaker has a layer option for polygons, it is not recommended to use it though. To change the order of appearance of polygons, go into ARRANGE MODE instead (press last button on the toolbar) and move polygons backwards or forwards. Only unlayered polygons (set layer to NONE, default) can be arranged. Shapes are drawn in the following order by default: polygons, lines, dotted lines and FS runways. Only set a layer if you want to force a shape type above another (polygon above a runway, for example). If you want a polygon to be drawn above a line for example, set its layer to 20.
Checking the NO LEVEL OF DETAIL option will deactivate LODs for that shape. This will only have any effect when LODs are enabled in the FILE\ PROJECT settings... menu item. LODs are for the advanced user only. Go to the LOD section to learn more.
It is possible to override the general polygon scale setting (FILE\ PROJECT SETTINGS...\ SCALES tab) by enabling the USES OWN SCALE option. This will force GroundMaker into using the scale entered in the input box for that polygon only. The scale has an influence on the texture pixel size and the accuracy of its outline. This feature is for the advanced user only.