POV-Ray : Documentation : Inverse Transform
  POV-Ray 3.6 Documentation Online View Transformation Order Transform Identifiers Inverse Transform

  transform { scale <20,24,28> translate y*3  inverse }

An inverse transform does the opposite of what the transform would normally do, and can be used to "undo" transforms without messing around with huge numbers of transformations. To do the same without this inverse, you would have to duplicate each transform, change them to do the opposite of what they would normally do (for example translate -y*3 instead of translate y*3)and reverse their order. Transformation Order Transform Identifiers

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