Sets the region-related KML attributes for a group of features destined for the OGCKML Writer.
Parameters
Region Bounding Box
Calculate from Feature Bounding Box
This parameter specifies whether or not the bounding box of the region should be computed from the bounding box of the feature's geometry.
If the value is Yes, the bounding box will be computed; if necessary, the calculated bounding box will be reprojected to the LL84 coordinate system. A valid coordinate system is required for the bounding box to be calculated.
Note: Setting a value of Yes on point features is not recommended because they have no area and will generate an infinitely small bounding box.
Buffer By
This parameter is only available when the region bounding box is being calculated from the bounding box of the feature geometry. It may be used to make the bounding box of the KML region larger (or smaller) than the bounding box of the geometry. The geometry bounding box will be expanded (or decreased if the value is negative) on all sides, by the value of the parameter. The parameter value should be given in degrees of latitude/longitude.
Display Criteria
Minimum Display Size
Minimum Pixels specifies the minimum size, in pixels, in the user's Google Earth view, that the region's bounding box must occupy before the region will become active – that is, when zooming in, at what point the feature should appear.
The smaller the value, the sooner the feature will appear when zooming into the view. A value in the range of 256 to 512 is recommended.
Maximum Display Size
Maximum Pixels specifies the maximum size, in pixels, in the user's Google Earth view, that the region's bounding box may occupy before the region will be deactivated – that is, when zooming in, at what point the feature should disappear again.
The smaller the value, the sooner the feature will disappear when zooming into the view. A value of -1 (infinite) is recommended. It means there is no maximum size and, once the feature has appeared, zooming in further will not cause it to disappear.
Minimum Fade Extent
This parameter specifies an offset to Minimum Pixels, in pixels, that determines the rate at which the region will be activated, and its contents displayed.
A value of 0 (immediate transition) is recommended.
Maximum Fade Extent
This parameter specifies an offset to Maximum Pixels, in pixels, that determines the rate at which the region will be deactivated, and its contents hidden.
A value of 0 (immediate transition) is recommended.
Bounding Box Parameters
Minimum X, Y/Maximum X, Y
These parameters specify the coordinates, in the LL84 coordinate system, that define the boundary of the region's bounding box.
Example
The default settings will calculate a bounding box, and use that as the bounding box for the feature's region:
The inactive view shows that the feature is not initially displayed when you are zoomed out. The region is "inactive" and therefore the feature is not shown.
As you zoom in closer, the view meets the display criteria and the region activates; that is, the feature displays.
Additional References
For more information about KML regions and how Level of Detail is calculated:
- See the FME OGCKML Writer chapter in the FME Readers and Writers manual (in Workbench, select Help > FME Readers and Writers Reference)
- See the KML documentation: http://developers.google.com/kml/documentation/regions
Editing Transformer Parameters
Using a set of menu options, transformer parameters can be assigned by referencing other elements in the workspace. More advanced functions, such as an advanced editor and an arithmetic editor, are also available in some transformers. To access a menu of these options, click 
beside the applicable parameter. For more information, see Transformer Parameter Menu Options.
Transformer Categories
Search FME Knowledge Center
Search for samples and information about this transformer on the FME Knowledge Center.
Tags Keywords: "Google Earth" KML