Obtain the center point of the Earth

Hello, I want to obtain the center point of the Earth and convert it into a Unity coordinate system. How can I obtain it? How to convert?

The center of the Earth is simply (0,0,0) in the Earth-Centered, Earth-Fixed (ECEF) coordinate system. You can convert ECEF to Unity coordinates using TransformEarthCenteredEarthFixedPositionToUnity on the CesiumGeoreference component.

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