Export 3d - KML for use in google earth web

hi there,

i have a geolocated model with some simple test geometry,

when i eport my model as kml for use inside google earth online, the model is at the right location, but its vastly oversized?!

how can i make sure the export gets done at the correct size?
by the way, model units do not seam to make any difference…

best, franz

Can you add a screenshot to your post? The description of what’s wrong can vary greatly between viewers.

If you have access to Google Earth Desktop, does it display correctly there?

A common error is to use inadvertently a bigger modelling unit than the user thinks he is using, for instance, meters instead of millimeters.

hey there together,

please see the image i have attached…

as i said, i have a very simple geolocated site, and just draw over the site plane 1:1 one of the buildings,
when exported as kml and imported in google earth web the the thing is kind of at the right place, but out of scale… :confused:

thx for any further input

in google earth desktop it works better, no scaling issues, but the placing is off a bit :frowning:

is this inside a usual or common error tollerance for this scenario?

I played around with Google Earth online and noticed two things:

  • It is based on Google Earth Desktop, and unfortunately on a buggy version which has a broken COLLADA (3d model) reader that causes models to be imported oversized and most of the time sheared (I believe this is only noticeable when there are nested groups).

  • It does not display textures on COLLADA models.

As far as I remember there was no workaround for this bug. If you have groups or components, maybe try exploding all? If it’s not skewed but just at wrong scale, maybe figure out the scale factor?

Otherwise if it is very simple geometry (extruded polygon) you could export not as 3D model (built-in kmz exporter) but as geometric primitives using a very old extension that may work or may not work anymore. Maybe there exist alternative export workflows (e.g. SketchUp → CityGML (?) → plain KML without models).

In both screenshots it is relatively well placed on the building footprint. This is the usual tolerance caused by image resolution, or still left after orthophoto correction (removal of distortions caused by terrain etc.).

You also see that as a geo/mapping-focussed company, Trimble licensed image sources with a top-down view (at the cost of lower resolution) where as Google chose nicer resolution from an oblique view, that means you cannot always be sure that what you are looking at is really positioned there.

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thanks for your input on this topic!