Tree lines
Tree lines simulate the vegetation surrounding your airport. A tree line is nothing else than a thin textured wall... You must use specially formatted textures for tree lines. These are split into horizontal stripes (bands), usually 8. You can choose one of the available bands to cover the tree line's surface. The texture will be repeated horizontally along the surface on both sides. Tree lines can also be used as fences or walls.
Seasonal and night effects can be enabled.
Notes on drawing tree lines
Tree lines should only be used around the airport, far away from the viewer. Don't make them too long; 1000 meters (3000') is a reasonable limit. Use tree macros (3D objects) in case you need trees near taxiways or terminals (for better realism).
Setting tree line properties
In order to access the settings dialog, make sure only one tree line 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.
Enter the the shape's height in the TREE HEIGHT input box.
There are no color options available since tree lines can only be textured.
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).
Check the CONSTANT BRIGHTNESS... options if you want the texture to shine at dusk, dawn and night. Make sure to disable the NIGHT TEXTURE option. GroundMaker will use the ShadedTexPoly() technique to light the surface. This option should not be confused with the option on the left, which requires an additional textures at night. Note that this option is for the advanced user only.
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.
You will find more info on textures by reading the TEXTURE topic.
MAPPING lets you apply the texture to the shape. Tree lines require a specially formatted texture which is split into horizontal stripes (bands). Textures can have 4 or 8 bands, 8 being the most common. Select one of the bands by clicking on the preview on the right. In FS, the selected band will be repeated along the tree line's surface. All tree line texture usually make use of 8 bands.
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. Tree lines should have a visual range of 4,000 to 6,000 meters.
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.