This page contains informations and thoughts about some tags and how they will be handled.

altitudeMode

• clampToGround -> will be ignored, Z = 0 in OGR, #
• relativeToGround -> Z in KML ==> Z in OGR, #
• absolute -> Z in KML ==> Z in OGR, 100% match

# points aren't exactly the same because of curvature of ground