????-??-?? Technology Preview 2
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* Previews scaling is now logarithmic (slower when zoomed).
* Previews drawing now takes advantage of multiple CPU cores.
* New texture model (perpendicular displacement and thickness).
* Added clouds hardness to light.
* Version management in saved files.
* Added ground texture and sun location in 3D explorer.
* 3D explorer now takes advantage of multiple CPU cores.
* Added sun halo control.

2012-04-20 Technology Preview 1
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* First preview version.