Slide set from tutorial given at the Web3D 2015 conference in Heraklion Crete in June of 2015. It goes along with a video linked from http://www.web3d.org/working-groups/geospatial.
Heraklion, Crete, Greece 18 - 21 June 2015
Geospa'al Component
• Special notes
– A scene may contain only 1 GeoOrigin
– Content with different GeoOrigins cannot be combined
– Advice is to avoid GeoOrigin as it prevents “mashing up” content
– In some cases it is useful:
• Some graphics pipelines require it for high precision scenes
• Use for rotateYUp to help support for different naviga'on modes
First the GeoOrigin coordinates are subtracted. Then, if rotateYUp is
requested, a rota'on matrix is computed based on how a GeoLoca'on
node would transform geometry with the GeoOrigin posi'on as the
GeoLoca'on posi'on. Finally, the calculated rota'on matrix is inverted
and applied to each vertex of the node.
6. GeoOrigin
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