2 GP Reference Entries

invert-transform

Function

Summary

Constructs the inverse of a transform.

Signature

invert-transform transform &optional into => inverse

Arguments

transform: A transform
into: A transform ornil

Values

inverse: A transform

Description

This function constructs the inverse of transform. If T is transform and T' is its inverse, then TT' = I. If into is non-nil it is modified to contain T' and returned, otherwise a new transform is constructed and returned.