# TAbstractX3DViewpointNode.GravityUp
Specify the gravity vector explicitly.
See http://castle-engine.sourceforge.net/x3d_implementation_navigation_extensions.php .
@deprecated

# TTransformNode.Center
Pivot around which the @link(Rotation) and @link(Scale) are performed.

# TTransformNode.Rotation
Rotate the children in 3D, around a given axis by a given angle.
Rotation is done around @link(Center).

# TTransformNode.Scale
Scale in 3D. Scaling is done around @link(Center)
and with orientation given by @link(ScaleOrientation).

We do the best we can to work with @italic(any) scale value,
even negative or zero. But usually, it's best to keep the scale
positive. See the @link(T3DTransform.Scale) documentation for some
good guidelines about the scale.

# TTransformNode.ScaleOrientation
Orientation in which 3D @link(Scale) is performed.

# TTransformNode.Translation
Translate (move) the children.

# TAbstractShapeNode.Render
Is the shape visible.
See https://castle-engine.sourceforge.io/x3d_implementation_shape_extensions.php#section_ext_shape_render
