Coordinate Systems and Transformations

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VRML uses a Cartesian, right-handed, 3-dimensional coordinate system.

The 2-D visualization of a object is obtained by :

projecting it in the positive Z-axis direction (X positive to the right and Y positive up); and
by transforming it if wished.

Transform is a grouping node that defines a coordinate systems for its children :

children [ ]
center 0 0 0 - C
rotation 0 0 1 0 - R
scale 1 1 1 - S
translation 0 0 0 - T

where

children, defines the elements affected by the transformation definition;
center, specifies a translation offset from (0,0,0) (local coord. system);
rotation, specifies a rotation of the local coord. system;
scale, specifies a non-uniform scale (must be positive) (local coord. system);
translation, specifies a translation to the local coord. system.

Being P a point, its new position P' will be :

P' = T . C . R . S . P Syntax :

Transform {

center C
rotation R
scale S
translation T
children [ .... ]
}