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18.4.2 Sheet Geometry Classes

Each of the following implements the sheet geometry protocol in a different manner, according to the sheet's requirements.

sheet-identity-transformation-mixin

Summary: This class is mixed into sheet classes whose coordinate systems are identical to that of their parent.

sheet-translation-mixin

Summary: This class is mixed into sheet classes whose coordinate systems are related to that of their parent by a simple translation.

sheet-y-inverting-transformation-mixin

Summary: This class is mixed into sheet classes whose coordinate systems are related to that of their parent by inverting the *
y*
coordinate system, and optionally translating by some amount in *
x*
and *
y*
.

sheet-transformation-mixin

Summary: This class is mixed into sheet classes whose coordinate systems are related to that of their parent by an arbitrary affine transformation.

CommonLisp Interface Manager 2.0 User's Guide - 27 Feb 2006