Achieving Compliance: OGC KML 2.2.0

Introduction

This article is part of the outputs of the article "OGC Compliant Formats with FME," which outlines the OGC-compliant formats that FME supports.

Examples

2D KML Features

Creating 2D OGC KML outputs in FME is very straightforward. Simply load in your data, then use a variety of FME’s KML transformers to style your features before using FME’s OGC KML Writer to output the features. 


If any issues arise, refer to the ogckml22.xsd to ensure that the output document satisfies all KML 2.2 schema constraints. 

3D KML Features 

FME’s OGC KML Writer also supports 3D KML features. This workspace adds elevation values to 2D building footprints using the 3DForcer to extrude building outlines, then customizes features using the KMLPropertySetter, finally creating a 3D KML output. 

Pro Tip

Sections ATC-112 and ATC-113 of the OGC KML 2.2 encoding document outline details about geometry extrusion and tessellation. In essence, these two elements should be mutually exclusive from each other. Also, take note that Section ATC-202 outlines that the 3D features should not have “clampToGround” defined as the altitudeMode element. The following example illustrates an OGC-compliant 3D feature as viewed in a text editor. 



The KMLPropertySetter allows you to customize these necessary elements for OGC compliance. Note that Geometry Tessellation can be toggled using the “Follow Terrain” parameter.