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<p class="MsoNormal">Section 5.3.13 in the X3D standard v3.3 describes the SFRotation field type; it offers a formula for deriving a rotation matrix from the field values.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Maybe the standard should mention that the matrix describes a *<b>passive</b>* rotation, not an active one. If the said matrix is applied to vertices straightforwardly while implementing the Transform node (which performs active rotation
of nested geometries), the rotation will be off by a sign, i. e. in the opposite direction.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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