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3.5.2 CLIM Transformation Protocol

transformation [Protocol Class]

Summary: The protocol class of all transformations. There are one or more subclasses of
transformation
that implement transformations, the exact names of which are explicitly unspecified. If you want to create a new class that behaves like a transformation, it should be a subclass of
transformation
. Subclasses of
transformation
obey the transformation protocol.

All of the instantiable transformation classes provided by CLIM are immutable.

transformationp [Function]

Arguments: object

Summary: Returns
t
if *
object*
is a transformation; otherwise, it returns
nil
.

+identity-transformation+

Summary: An instance of a transformation that is guaranteed to be an identity transformation, that is, the transformation that "does nothing."

transformation-error

Summary: The class that is the superclass of the following three conditions. This class is a subclass of
error
.

transformation-underspecified

Summary: The error that is signaled when
make-3-point-transformation
is given three collinear image points.

reflection-underspecified

Summary: The error that is signaled when
make-reflection-transformation
is given two coincident points.

singular-transformation

Summary: The error that is signaled when
invert-transformation
is called on a singular transformation, that is, a transformation that has no inverse.

CommonLisp Interface Manager 2.0 User's Guide - 30 Jul 2004